MikeC
Admin
Reged: Sun
Posts: 4426
Loc: Orlando, FL
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12:30AM Update - 05/23/09
Just as it seemed that the gulf low was written off, it has managed to develop some convection near the center. The low is still disorganized not close to being classified at this time, but the has given the system a 30 - 50% chance to develop into a tropical depression in the next day or so before it makes landfall.
10AM Update - 05/21/09
Upper level low pressure system beginning to develop a surface reflection near 25.5N 86W at 21/13Z and it is currently drifting to the north northeast. Upper level steering is weak (and the upper low is cut off) but forward motion should become more north northwesterly to northwesterly in the next day or two - perhaps more toward the Alabama/Mississippi state line - keeping Florida in the soup for another day or two. Flooding potential likely to continue in east central Florida through Friday with additional heavy rainfall over already saturated areas.
ED
7:00 PM Update 5/19/09
Chances for development have fallen off greatly, but we are still getting loads of rain in Central Florida.
10:00 PM Update 5/18/09
Nothing much new to report, models project the system to move more northward then westward across Florida. There is less than a 30% chance of anything developing from this system. Rain over Florida will continue to be enhanced by the system.
Winds will stay brisk because of the pressure gradient, closer to a subtropical or system.
Site fixes tonight include the animated model plots working (see bottom of this article), and a few other minor tweaks. General Info is still broken currently. (Pre-Season disturbance is rushing a few things)
2:30 PM Update 5/18/09
The system mentioned here is being tracked as Invest 90L now, being early, automated tracking here and on some other sites may take a while to show up.
Approx 22.4N+76.0W (Near the Bahamas)
More to come soon...
Original Update
It looks to be a wet week coming up across most of Florida.
A low pressure system near Cuba looks likely to interact with a frontal boundary causing a great deal of rain for mid-week here in Florida, with the gradient making it a bit windy. Although development isn't entirely likely, the system currently over Cuba has the potential to become somewhat tropical, although it likely will remain just a low pressure area.
Models (such as the and EURO -- see some Here) currently project it to move into or just west of south Florida then stay west of Florida and move it into the Central Gulf near Alabama to Missouri. This may change later. There are no indications of strengthening, but it is worth watching. The front and the gradient should keep things wet and breezy in Florida through the middle of the week. This is good news for the fires in the Central Florida area, as long as the rain comes with the gradient winds.
Even though Hurricane Season does not officially start until June 1st, we will be watching it.
91L Event Related Links
SFWMD Model Plot (Animated Model Plot) SFWMD Hurricane Page
[https://flhurricane.com/floatanimator.php?year=2009&storm=1 Flhurricane Satellite Floater Animation of 91L
GOES Floater
Animated Model Plot of 91L
Clark Evans Track Model Plot of 91L
(Animated!) Model Plots in Google Earth - In Google Maps
Clark Evans Intensity Model Plot of 91L (Animated!)
Clark Evans Track Plot of 91L
Other Model Charts from Clark
Clark Evans Top 10 Analog Storms for 91L
More model runs on from RAL/Jonathan Vigh's page
NRL Info on 91L -- RAMMB Info
COD Atlantic Satellite View
Cuban Radar
Southeastern US Radar Mosaic
Tampa Bay, FL Radar Radar Loop
(Latest Static)
Key West, FL Radar Radar Loop
(Latest Static)
Miami FL Radar Radar Loop
(Latest Static)
Melbourne FL Radar Radar Loop
(Latest Static)
StormCarib Reports from the Caribbean Islands
Caribbean Weather Observations
Barbados Brohav Weather Fax
Full Caribbean Radar Composite
Caribbean Broadcast Corporation (TV/Radio from Antilles)
San Juan, PR NWS Page
Various Caribbean Radio Stations
DR1 Dominican Republic Hurricanes
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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The Season Starts Early Again.... Questions will be..is this tropical or subtropical...probably subtropical until it gets more into the gulf, but too early to tell. Models are converging on a Florida rainmaker and extact strength is up in the air for now. Lets just wait for more model runs thru Monday 12Z to find a good scenerio.. I feel a hurricane hunter might go check this out Monday afternoon or Tuesday.
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docrod
Weather Watcher
Reged: Tue
Posts: 36
Loc: Florida Keys, Key Colony Beach
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So far - here in the Keys - we've barely gotten any rain from it (well Key Largo got a good drenching). Been nearly a month without rain. Not too happy however about a season trying to start early. - take care
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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I'm not too worried about this system developing, but I am worried about potential tornadic activity that this system interacting with a frontal boundary over Florida may cause, so I'll definitly keep my eyes open over the next few days when I'm out and about.
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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Well really thats all this system is going to be.. a big rainmaker florida..the tornado threat will be there also..especially to the north and east of the system. I dont feel this will be tropical..maybe subtropical. Cold air aloft and shear will hamper any real tropical develoment.
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MikeC
Admin
Reged: Sun
Posts: 4426
Loc: Orlando, FL
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A few things this morning, models are still a bit wonky on this one, but there is no low level circulation with this low, it may develop something at the low levels a day or two from now. Most of the precipitation will likely be on the eastern to southern sides, ala Florida. If this were July or August, we'd really have to be careful. Here in May, it's a welcome sight for parts of Florida that need the rain badly.
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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I've been watching the satellites this morning and the forecast area of interest in the Caribbean is undergoing development at a fair pace.
I would rank it at a 5 or 6, with 10 being rapid development.
Currently the SE and Southern side of the system has the most convection. Time will tell.
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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Coincidence or not. Recon has a plane in St Croix as of Mid-Afternoon on Saturday (yesterday).
AF304 landed approximately 1943Z.
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Storm Cooper
User
Reged: Sat
Posts: 1290
Loc: Panama City , FL
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It is getting attention.....small part of TAE discussion...
ALSO...THIS SYSTEM HAS THE POTENTIAL TO ACQUIRE
SUBTROPICAL CHARACTERISTICS OVER THE CNTRL/ERN GOMEX DURING THIS
TIME...AND WILL BE MONITORED CLOSELY DURING THE NEXT SEVERAL DAYS.
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Hurricane Season 2017 13/7/1
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weathernet
Storm Tracker
Reged: Sat
Posts: 296
Loc: Elsewhere
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Bear watching......
Could be transient, but this area just east of Jamaica has really started to appear to "spin up". Albiet small and likely mid level, will be interesting to see if the upper air will relax enough to permit an eventual stacked system to form. In this case, I could see eventual tropcal characteristics ( as opposed to simply subtropical ). Have not yet even looked at surface obs or SST's as of yet, however.
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MichaelA
Weather Analyst
Reged: Thu
Posts: 914
Loc: Pinellas Park, FL
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SSTs in the eastern Gulf of Mexico are running between 80 and 82ºF, so there is some heat content to work with. I'm not sure if this goes to any depth, but these temps are conducive to some development. At any rate, it will be an interesting week here in West Central FL. We certainly need the rain.
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Michael
WU PWS
2021 “guess:” 15/8/3
2021 Actual 21/7/4
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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Kingston Jamaica Airport Observations for the last 6 hours.
Last four obs show a veering wind. Indicative of a N to NE movement of system generating the wind. This is a rough estimate.
14z 270 at 7kt system should be North of Airport
17z 330 at 10kt system should be NE of Airport
MKJP 171700Z 33010KT 9999 FEW018 BKN090 BKN220 25/21 Q1012
MKJP 171600Z 31008KT 9999 FEW022 SCT034 BKN090 25/21 Q1012
MKJP 171500Z 28005KT 99999 -RA FEW018 BKN080 24/21 Q1013
MKJP 171400Z 27007KT 99999 -RA FEW022 BKN080 24/21 Q1012
MKJP 171300Z 32008KT 9999 -RA FEW022 OVC080 23/21 Q1012
MKJP 171200Z 09008KT 9999 -RA FEW022 OVC080 24/22 Q1012
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weathernet
Storm Tracker
Reged: Sat
Posts: 296
Loc: Elsewhere
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interesting........Those Jamaica obs you posted would at least indicate some reflection at the surface. Perhaps a weak wave is mixed up within this "trough soup"? BTW, those SST's I think Michael referenced in the E. Cenral Gulf of 80-82F, even if shallow, could easily substantiate subtropical or tropical development.
Won't even dare look at the model; am sure its got some low wraped with over 3,000 tightly packed isobars around it. Intensity ( and humor ) aside, can anyone tell me if the Canadian model at least has proven marginally effective in any aspect of tropical cyclone forecast such as motion?
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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Latest satellite INVEST images from GOES TropFlot One shows some of the convection around the approx center of circulation dying down some, but the circulation does appear to be mid-level in nature, with maybe a hint of low level visible now.
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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I don't have statistics on the Canadian Models versus the other Tropical models.
I do recall over the last 4-5 years that the Canadian is usually the one to lead the pack in early prediction.
It performed very well in 2004 and 2005...
Unless they have changed some of the parameters of the models like the U.S. does every year it should be the first one to check.
I use it first and cross check with the , UKMET and for starters.
Use Dr. Robert Hart's site at for a full days worth of weather data viewing.
http://moe.met.fsu.edu On left side of page click the "Web Pages" link and enjoy.
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Lamar-Plant City
Storm Tracker
Reged: Mon
Posts: 375
Loc: Plant City, Florida
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Nice to see everyone back on their game! Hope everyone had a great off-season (sounds like a sporting event).
It would be GREAT to have a major rain-maker here in central FLA this week! We are at 2 years drought and counting right now. Tampa is now allowing ZERO lawn watering in the city limits. (another good reason NOT to live in the city!) Had about 4 inches this week in Plant City, but we need more than a foot of rain to START overcoming the long-term drought. AND had some reports of hail this week....in one location so thick it covered the ground. POPs for here this week are wavering around 60% at this point and this system could do a LOT for us. Bring it on!
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If you don't like the weather, wait 5 minutes...
2017 Season Prediction: 16/7/3
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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Mid Level seems to be there, can it work it's way down to the surface? Think so.
http://www.ssd.noaa.gov/goes/flt/t1/flash-ft-s.html
Some great loops to watch various levels and slice and dice your way through the system.
A lot depends on where the front stalls out and where the center forms..when it forms. Model tracks will change once there is something at the surface.
Good to see everyone back... good to be here!
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http://hurricaneharbor.blogspot.com/
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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Yeah, forum activity is off to a sudden and new start. Even though forum discussion is just now starting, I've been visiting the site frequently during cold front season to get updates on weather advisories and warnings.
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HCW
Storm Tracker
Reged: Fri
Posts: 287
Loc: Mobile,AL
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I realize that everybody is expecting some much needed rain from this system in Florida but lets think back to 2007 When Sub Tropical Storm Andrea formed and caused some of the worst fires that the state of Florida as ever seen. It's nice to see everybody again and I hope that you have a safe 2009 cane season James n Mobile,AL
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Over 4,000 members and now on a new server
http://www.hardcoreweather.com
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craigm
Storm Tracker
Reged: Wed
Posts: 326
Loc: Palm City, Florida
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Hello everybody! Time to come out of hibernation. Looks like we could get some badly needed rain out of this early system. and ukmet bring rain into Florida. I see the is up to its old tricks.
http://moe.met.fsu.edu/cgi-bin/cmctc2.cg...&hour=144hr
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Why I'm here:
Weather hobbyist
Edited by craigm (Sun May 17 2009 09:32 PM)
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Storm Hunter
Veteran Storm Chaser
Reged: Wed
Posts: 1370
Loc: Panama City Beach, Fl.
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looks like the guys are following the suite?
have a low off miami in 48hrs... tracking along coast, before a left hand turn across the state in to NE GOM.
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www.Stormhunter7.com ***see my flight into Hurricane Ike ***
Wx Data: KFLPANAM23 / CW8771
2012== 23/10/9/5 sys/strms/hurr/majh
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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Thank you! I needed that lol. Well... the point is that the models have not lost it and maybe they do need to be fine tuned.
I think i am going to go stare at some loops... and be grateful for this board.
someone please let me know when there is an invest.
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http://hurricaneharbor.blogspot.com/
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cchsweatherman
Weather Watcher
Reged: Tue
Posts: 34
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Been tracking this disturbance for the past few days ever since the computer models began suggesting this disturbance could develop and must say that this is the best structurally the disturbance has looked to date. Even though the convection has waned, the mid-level circulation has vastly improved as opposed to just 24 hours ago and it seems that it may now be starting to translate down to the surface as recent observations have been indicating shifting winds and the CIMSS 850 MB Vorticity Product indicates that low-level vorticity has been increasing. Also, wind shear has also been steadily decreasing over the system throughout the day and continues to do so according to the CIMSS Shear Tendency Product. Overall, it seems that we may indeed be watching some gradual development occuring with this disturbance.
Earlier on my CCHS Weather Center site I had created a graphic showing the driving forces behind the projected movement and eventual impact on Florida from this system. Below is the graphic.
Graphic
I will have a new update regarding the system on my site sometime tomorrow. Have a good night you all and it feels to good to return to this great site.
Edited by cchsweatherman (Mon May 18 2009 02:06 AM)
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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I'm not sure your aloud to post something with a picture taking up soo much space like that...but maybe things have changed.
Anyways the 0z run on the doesnt show much @ all... just a trough of low pressure from the Keys to the Bahamas with a low on its eastern end...then migrating back west in response to a building ridge. Florida looks like rain..but as a weak 1007mb extra-tropical low...infact the is showing alot of dry air working its way into the system. I guess we will tell in time!
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MichaelA
Weather Analyst
Reged: Thu
Posts: 914
Loc: Pinellas Park, FL
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The IR loop seems to indicate a low level circulation moving off the coast of Cuba. The models are not being quite as aggressive with this system this morning.
Floater - Infrared Channel 4 Loop
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Michael
WU PWS
2021 “guess:” 15/8/3
2021 Actual 21/7/4
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Beach
Weather Guru
Reged: Wed
Posts: 187
Loc: Cocoa Beach/Banana River
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Hey Michael..
Yeah I see the rotation, but I'm not sure if it's the "center"
http://www.ssd.noaa.gov/goes/flt/t1/loop-vis.html
21N 76W
Unfortunately there aren't any Bouys in the area:
http://www.ndbc.noaa.gov/maps/Florida.shtml
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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I see the low level circulation as well, and there seems to be convection firing up just to the east of the center of circulation and trying to wrap around it a little bit, although something, probably some dry air, is keeping the west side of the system devoid of any significant storms. It seems the circulation reformed overnight from it's previous position to a new position of 21.75N and 76W, which appears to be generally moving to the NW.
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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So my question is..is there one model in particular that saw that coming or is handling this set up better than another.
Are we sure how far south this "unusually strong late season cold frontK is going to go.
May storms can be as hard to predict as November storms in ways.
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http://hurricaneharbor.blogspot.com/
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weathernet
Storm Tracker
Reged: Sat
Posts: 296
Loc: Elsewhere
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Looks to me ( and as others have already observed ) that some low level swirl seems to have migrated to around 21N and 76W. Looks as if a broader mid level vorticity is slightly southeast ( perhaps around 20N & 75W ). While it is hard to really pinpoint which feature to follow, it would appear as if the overall motion now does seems to be between NNW and NW.
Looking at 0Z to 12Z data, my bet is on a UK/NAM solution. I think both have now for about 24 hours tracked a weak low ( 1004mb ) NNW to about West Palm Beach area, then turned it westward under a building ridge from the north, only to deepen the low a little in the E. Central Gulf, and finally northward from there. Latest continues the thinking, except the timing a tad slower with a 1004 low just off S.E. Florida in about 42 hours. Forecast from there does the same but never really deepens the low to much in the Gulf.
All this aside, while SST's are certainly adequete for tropical develpment, the 12Z 200mb winds just seem to be screaming, and even after the trouph pulls out, while the upper air does appear to become more difluent, it still appears rather hostile for any real tropical system to develop. A nice anticyclone is starting to build in at the latter part of the forecast period but appears to be somewhat to the north and over the . Hard to see current forecast maps verify, and have more than a subtropical depression ( maybe weak TS ) at most in the 4-6 day range somewhere along the N. Gulf coast. Should be just what the doctor ordered - a good rainmaker!
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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Any chance the model is reading 2 different systems?
This is way outside the box... subtropical rides up bahamas and warm core develops at tail end of front west of fl in the GOM.
Looking at sats... something compelling about what is vs trying to see the future with models.
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http://hurricaneharbor.blogspot.com/
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byrdlh
Registered User
Reged: Wed
Posts: 7
Loc: Panama City, FL
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What is the chance it will effect the panhandle? I am following the analysis here, but am concerned due to outdoor high school graduation at the end of the week. Will it track more to the west? What is the possibility that the front moving through now (it is only 68 in PC today) will keep it to the west of us. We need to be able to make appropriate plans...do have backup just in case.  )
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Lois
Unregistered
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"All this aside, while SST's are certainly adequete for tropical develpment, the 12Z 200mb winds just seem to be screaming, and even after the trouph pulls out, while the upper air does appear to become more difluent, it still appears rather hostile for any real tropical system to develop. "
Yes... looking at the set up and the strength of King as he is sometimes called... I don't see how anything can develop just yet. And, won't even give it a 30% chance (let me know if that changes, at work and just looping)
http://cimss.ssec.wisc.edu/tropic/real-time/tpw2/natl/anim/latest72hrs.gif
Look at that.. just LOOK
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MikeC
Admin
Reged: Sun
Posts: 4426
Loc: Orlando, FL
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The system is being tracked as Invest 90L now, being early, automated tracking here and on some other sites may take a while to show up.
Approx 21.9N, 75.8W
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MikeC
Admin
Reged: Sun
Posts: 4426
Loc: Orlando, FL
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You may want to check the front page for the new Special released Tropical Weather outlook.
I think it's a first for that to have been modified out of season.
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MichaelA
Weather Analyst
Reged: Thu
Posts: 914
Loc: Pinellas Park, FL
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It's going to be an interesting week whether this system continues to develop or not. The rainfall is welcomed here in West Central FL, although today's rain is from the frontal trough.
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Michael
WU PWS
2021 “guess:” 15/8/3
2021 Actual 21/7/4
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rhendryx
Verified CFHC User
Reged: Wed
Posts: 23
Loc: Tampa, FL
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Echoing sentiments of others from West Central Florida. This rain is much needed and hope it continues all week. I told my wife over the weekend that with any luck this would be a significant rain maker that could go along way to quenching the thirst of this nasty drought. Light rain and drizzle most of the day in Valrico has been most welcome.
Not happy that hurricane season is rapidly approaching, but glad to see familiar names back at flhurricane.com.
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docrod
Weather Watcher
Reged: Tue
Posts: 36
Loc: Florida Keys, Key Colony Beach
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Hi - the rain is about to move through our area in the Keys ... 'bout time.
From the vis sat loop, 90L appears to be having a rough go of it this eve. We shall see in the morning.
- take care - Rod
vis loop
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Storm Hunter
Veteran Storm Chaser
Reged: Wed
Posts: 1370
Loc: Panama City Beach, Fl.
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Looking at data all day and last night... i'm wondering now if will see two lows out of this? 90L, which has already formed.... will move up the east side of Florida, before turning back across the state in a few days into the GOM. And a second...subtropical low that will form out in the southern GOM in the next day or two off the tail end of the front thats coming through... i would expect the second low to be weaker and move more west of southwest through the eastern/central GOM..... anyone think there be two lows? on possible tropical.. another subtropical?
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www.Stormhunter7.com ***see my flight into Hurricane Ike ***
Wx Data: KFLPANAM23 / CW8771
2012== 23/10/9/5 sys/strms/hurr/majh
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k___g
Weather Guru
Reged: Fri
Posts: 110
Loc: Leesburg, FL
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I've looked at the info and think this will be the rain-maker that central and south Florida needs. I don't see any significant tropical development, due to 1) upper level shear and 2) historical climatology.
As an aside, it's nice to see several regulars back. I don't often post but read everyone's input.
Looking forward to an exciting 2009!!!
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docrod
Weather Watcher
Reged: Tue
Posts: 36
Loc: Florida Keys, Key Colony Beach
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I'd agree - a chance. I've not been through all the data but has certainly suggested that in some runs, and the disturbed weather moving into South Florida is shuffling the deck on all of us. I also think 90L may be breaking up but we shall see.
Regardless, our field work north of Key West tomorrow morning is canceled till Wed or maybe Thr.
- take care
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mikethewreck
Weather Hobbyist
Reged: Wed
Posts: 52
Loc: Treasure Coast FL
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The frontal system has already taken at least one life. A friend of our family, 18 year old kid, was playing outside with friends in MS when the front came through. Hit by lightning. Died today. 
Saw on a weather site (accuweather) that this system could become a named storm, headed over here as soon as I could. Much comforted. Have I told you today how much I appreciate all of you?
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Earliest memory Hurricane Cleo!
Went under Hurricane Gloria!
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k___g
Weather Guru
Reged: Fri
Posts: 110
Loc: Leesburg, FL
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Latest radar from Melbourne shows two circulations...one east of Ft. Pierce and the other between Orlando and the east coast south of Daytona.
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docrod
Weather Watcher
Reged: Tue
Posts: 36
Loc: Florida Keys, Key Colony Beach
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Sorry to hear that - we canceled our field work this afternoon for tomorrow watching all the lightening in this system. Sad.
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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Sounds trite maybe but we are a family. Like tropical soup and so many components. Watching pressure drops all over. Nice spin and more scenarios than rain. Rapidly developing situation.
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http://hurricaneharbor.blogspot.com/
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docrod
Weather Watcher
Reged: Tue
Posts: 36
Loc: Florida Keys, Key Colony Beach
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below is pasted from Key West NWS tonight - our local radar shows signs of a rotation basically west of Key West but I admit this is speculation. Safe to say - it's a mess out there.
SURFACE ANALYSIS DEPICTS A VERY COMPLEX PATTERN ACROSS THE REGION.
THERE APPEARS TO BE A WEAK LOW PRESSURE AREA IN THE YUCATAN CHANNEL...
AND ANOTHER WEAK SURFACE LOW NEAR THE CENTRAL BAHAMAS. A STATIONARY
FRONT LIES ACROSS SOUTH FLORIDA AND THE SOUTHERN GULF OF MEXICO...
WITH STRONG HIGH PRESSURE AND NORTHEASTERLY FLOW COVERING THE GULF
TO THE NORTH OF THIS FRONT. AT MID LEVELS...AN EQUALLY COMPLEX
PATTERN PREVAILS...WITH AN UNSEASONABLY STRONG SHORTWAVE STARTING TO
CUT OFF OVER THE EAST-CENTRAL GULF...AND A SEPARATE CYCLONIC
CIRCULATION MOVING SLOWLY NORTHWARD BETWEEN CUBA AND THE CENTRAL
BAHAMAS. AT UPPER LEVELS...THE KEYS LIE UNDERNEATH STRONGLY DIFFLUENT
FLOW...ALONG THE LEADING FLANK OF A SHARP TROUGH OVER THE EASTERN
GULF.
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Rick99
Unregistered
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I donno', seems like there's a large scale circulation encompassing all of south Florida.
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adam s
Unregistered
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what are the chances 90L becomes a tropical depression or a tropical storm?
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HCW
Storm Tracker
Reged: Fri
Posts: 287
Loc: Mobile,AL
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Quote:
what are the chances 90L becomes a tropical depression or a tropical storm?
Not very good since we haven't had model runs since 00Z. Time to watch for development in the GOM closer to the cold front and that would be INVEST 91L if we even get that far . Still looks like a very wet holiday weekend up here on the Alabama Gulf Coast
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Over 4,000 members and now on a new server
http://www.hardcoreweather.com
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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Its going to take some time for the low in the straits to be subtropical... maybe 2-3 days...right now its a typical North American low pressure system in all level of the atmosphere with a warm front out to 70W which ingulped 90L....90L though will still be out there (though not designated) it be more like a trough.
Overall the cyclonic low in the straits will move NW off Sarasota tonight then west into the eastern GOM on Weds...alot of rain and strong T-Storms over florida..especially on Weds as florida will be on the humid E side and cyclonic turning in the atmosphere may cause a tornado watch in parts of the state.
91L from this..maybe in a few days!
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weatherguy08
Weather Hobbyist
Reged: Thu
Posts: 60
Loc: Miami, Fla.
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I think what could be of interest is a trough of low pressure in the Florida Straits, at least it was there Monday evening, I haven't done a surface analysis this morning yet. My surface analysis showed a trough extending from north of Grand Bahama to near the Cayman Islands. Once this thing begins interacting with the front, we could see something spin up in the southeastern Gulf or the Florida Straits.
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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There is still a better chance..old 90L races westward tonight into Weds and develops a small tight core of only 25 miles with winds in excess of 45-50kt (cause of the ridge to its north giving a pressure gradient)to its north side coming ashore from Cocoa Beach to Daytona .... then the cyclonic low off Naples developing in the next 48 hrs...
cyclonic low off SW florida is just that...and not tropical...it will take a few days to become that..and by then...it may have too much dry air that comes down from the southern mississippi valley and really hamper this thing.
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docrod
Weather Watcher
Reged: Tue
Posts: 36
Loc: Florida Keys, Key Colony Beach
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yer right; at mid-level -that was impressive all day - had a great time watching it all morning; but down low it was a mess.
happily 90L-May 2009 is in the books. I don't need 91L anytime soon.
Stay safe everyone - cheers Rod
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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It's begun. Tornado warnings have been issued at least three times so far tonight, for thunderstorms moving across Apopka, Cassia, and Titusville. The one for Cassia is still in effect. I seem to be suffering insomnia right now, I hope it's not because something big is in my blood for the rest of the upcoming day today.
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vineyardsaker
Weather Guru
Reged: Wed
Posts: 146
Loc: New Smyrna Beach, FL
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We had a horrible night in New Smyrna Beach. The weather radio warned of two tornadoes south of us, but reports this morning say that a tornado also hit north of us in Port Orange. This morning the winds and rains have picked up *a lot*, the water in our canal is high, the thunderstikes are amazing. One was so loud that I actually saw my walls shaking! We could not even walk our dogs due to the lightening risk (the poor guys could only do their stuff front of our house on very long leashes). I have been living here 7 years now, but this is the worst (non-cyclonic) weather I have ever seen.
What is going on here? Why is there so much thunder and lightening in the air? This is not a cyclone, ok, but is that just a "regular" thunderstorm stuck over East-Central Florida for three days?!?!
Where is all this power coming from?! Not form the tepid waters of the Atlantic, is it?
Take a look at the attached file. Looks like New Smyrna is gonna get it hard today
Thanks for any explanations about what is going on here 
Thanks!
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Charley(eyewall), Ivan, Jeanne, Dennis, Wilma, Irma
Edited by vineyardsaker (Wed May 20 2009 12:01 PM)
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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cyclonic lows or cold core lows aloft like the 1 we have produce alot of lighting...you have temps about -10 to -15C high in the atmosphere while temps in the lower levels are in the 70s with humid moist conditions. The updraft is really strong producing these high cloud tops. This also produces hail...and its very common with cold core systems aloft... this mainly happens over the plains!
If this was tropical in nature...it would be warmer aloft...thus not producing hail...and alot less lightning.
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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I'm kind of hoping it doesn't come my way, but even as I say this, I'm looking at animated doppler radar at several lines of thunderstorms advancing over Polk County. It may be just to our north for awhile, but it looks like we'll get some rain later on in the afternoon, which I don't mind. I do mind significant sized hail and tornadoes though. Shoo shoo.
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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Mobile NWS offers a great summation in the Afternoon Forecast Discussion.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOBILE AL
230 PM CDT WED MAY 20 2009
SHORT TERM...FORECAST ISSUE REMAINS TO BE THE EVOLUTION OF THE LOW
OVER FLORIDA OVER THE NEXT 48 HOURS. THERE APPEARS TO BE A WRAPAROUND
DRY SLOT FROM THE MIDLEVEL MID-LATITUDE JET STREAM ALL THE WAY AROUND
THE WESTERN GULF TO THE YUCATAN AND THEN CUBA. THERE IS A 500 MB
TROUGH THAT IS ALSO KEEPING THE AIR PRETTY COLD OVER THE SURFACE
CENTER. VERY LITTLE ABOUT THIS SYSTEM IS BAROTROPIC...THERE IS
CONSIDERABLE ADVECTIVE PROCESSES TAKING PLACE WITHIN THE LOW. ALL OF
THAT BODES ILL FOR TROPICAL CONVECTION IN A DEEP MOIST LAYER THAT ONE
WOULD EXPECT IN AN EASTERLY WAVE EVOLVING INTO A TROPICAL CYCLONE.
WITH ALL THIS DRY AIR AROUND...ENTRAINMENT OF SAME INTO CUMULUS
TOWERS WOULD KILL THEM OFF BEFORE ANY LONG LIVED CONVECTION COULD
DEVELOP. SO THIS SYSTEM WOULD BE HARD PRESSED FOR THE NEXT 2 DAYS OR
SO TO LIGHT OFF SUCH A CONVECTIVE CORE REQUIRED TO TRANSITION IT INTO
A WARM CORE SYSTEM SUCH THAT THE SURFACE PRESSURES COULD FALL. THAT
IS...SLIM AND NONE ARE THE RANGES OF PROBABILITY THAT THIS LEOPARD
WOULD CHANGE SPOTS TO STRIPES WITHIN THE NEXT 48 HOURS.
http://www.srh.noaa.gov/printable.php?pil=AFD&sid=MOB&date=2009-05-20%2019:30:32
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JMII
Weather Master
Reged: Thu
Posts: 422
Loc: Margate, Florida
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Very interesting watching the radar out of Miami during the last few days... you could clearly see the circulation center move W and pull all this rain into FL. Given the water levels in my backyard and the fact that we had some new sod put down last week I was glad we finally got a good soaking.
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South FL Native... experienced many tropical systems, but actually had to put up the panels for:
David ('79) - Floyd ('87) - Andrew ('92) - Georges ('98) - Frances ('04) - Wilma ('05) - Matthew ('16) - Irma ('17)
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vineyardsaker
Weather Guru
Reged: Wed
Posts: 146
Loc: New Smyrna Beach, FL
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Another bad night in Volusia County. Huge amounts of rain overnight with thunder and lightening in New Smyrna Beach. Lots of flooding in Ormond Beach too:
Several majors roads are closed in Port Orange (Dunlawton between US1 and Nova).
In my garden an upturned bucket now has over a foot of water, thought at least in the canal in front of my house the water is high, but not catastrophically.
I know we needed the water (had some brushfires just before the rain began), but that is a little too much of a blessing I think
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Charley(eyewall), Ivan, Jeanne, Dennis, Wilma, Irma
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key
Unregistered
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satellite image is very impressive at the moment. Anyone else think that politics rather than science is preventing this from being a named storm???
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MikeC
Admin
Reged: Sun
Posts: 4426
Loc: Orlando, FL
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It's not political. The surface low is still very weak, and definitely nowhere near named or depression status. It may get re-tagged as an invest area tonight or tomorrow if the surface low persists.
Water temps in the direction its moving get cooler, although general shear is decreasing. The movement is pretty slow, however.
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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Over the last 5 to 6 hours the visible satellite shots together with the IR enhanced imagery seem to indicate that the LOW might... might be trying to close off the center. At present the IR enhancement reveals an approximate 30 to 35% segment that continues to encircle the center. Starting at the southeastern side of the center and circling counterclockwise around toward the northwestern side of the center.
Probably have to run a 6-8 hour loop to see the development as it is very slow.
NWS Slidell,LA radar is beginning to indicate showers in MS as far north as the 31degree north latitude line at Poplarville/ Lumberton,MS.
East GOM Buoy 42003 at 17Z indicating pressure at 1006.5mb winds SE or 120deg at 16gusts to 19kts peak gust to 23kts.
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Storm Hunter
Veteran Storm Chaser
Reged: Wed
Posts: 1370
Loc: Panama City Beach, Fl.
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well the low is easy to track now... and i think there still a 15-25kt shear right above the low at the surface.. should weaken over night, i would expect.. there clearly is a nw dift/movement today... a bit it is slow.. so eratic movement should be noted... i would expect this to get tagged again, atleast an Invest with a new number.. since this is clearly a not the original low from the bahama's...
Track the LOW with Vis
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www.Stormhunter7.com ***see my flight into Hurricane Ike ***
Wx Data: KFLPANAM23 / CW8771
2012== 23/10/9/5 sys/strms/hurr/majh
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JoshuaK
Weather Guru
Reged: Mon
Posts: 157
Loc: Central Florida
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According to the Satellite visible loop and other data, it appears that there are two different circulation centers associated with this system. The more defining one is located at 26N 87W as of this posting time (4:41PM EST) and consists of a mid to low level circulation, and is crawling west. The second circulation center, consisting of a high level circulation, is located at 27.5N 86W and is again crawling west.
The system is looking a little better today, but is still a long ways off from developing into anything significant. Although there is still some dry air present, the last few water vapor slides in the loops shows the dry air pocket in the central GOM closing up as more moisture works in from the west.
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scottsvb
Weather Master
Reged: Mon
Posts: 1180
Loc: fl
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The system is 70% cold core...low level tropical moisture is being pulled north...but its COC is cold core. This doesnt have enough things going for it to become a subtropical storm.. I said 25% chance last night...and I'm sticking with that. The water infront of this is cooler in the mid 70s...right now its near 80 as of 6z Fri. Even though I dont think this will make a subtropical depression....tropical moisture from the lower levels along with the unstable cold core low in the mid levels will produce T-storms out as far as Florida..with this coming ashore in Louisiana.
Side note... models are persistant in the ,ECMWF and on keeping pressures low in the bahamas and florida... a low may develop again near Cuba, southern Bahamas, or near Andros Island again and move north along the east coast of Florida early next week... 30% chance this will happen cause its too far out to actually really care. Don't want to say this has a chance cause windshear will be high until it reaches the northern Bahamas and Florida.. Water temps are marginal...but this will be more tropical like 90L and not what is in the GOM right now....if there is anything at all!
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HCW
Storm Tracker
Reged: Fri
Posts: 287
Loc: Mobile,AL
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This area is now invest 90L again. Shouldn't this have been given a new number since it is not the remnants of 90L ? Looks like it's running out of time and will be inland tomorrow morning and not worth sending recon into. James N Mobile
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Marknole
Weather Watcher
Reged: Sun
Posts: 45
Loc: Wacissa, FL
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From "Nearly nil chance of development" to this (NWS Tallahassee AFD, 2:30 PM):
SHWRS/ TSTMS INCREASING WHERE MOIST DEEP SELY FLOW WILL
ADVECT NWWD FROM GULF AND BE PERIODICALLY ENERGIZED BY SEVERAL
IMPULSES OF ENERGY ROTATING NEWD ON THE EAST SIDE OF LOW. LATEST
SATELLITE PIX HINT AT DEVELOPMENT OF A CIRCULATION.
Tropical airmass in place here in the Big Bend, along with distinct banding features. Certainly warm enough SST's over the central gulf. Any information from the met's?
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Storm Hunter
Veteran Storm Chaser
Reged: Wed
Posts: 1370
Loc: Panama City Beach, Fl.
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i think there was a mid to upper level low that spun around the northern part of the low level low and caused some decent wind shear yesterday and today... if you look at WV loops in the last 24 hrs... it spins right off the Florida Phn coast tracking NW... its much weaker now.. which i think is opening the door some now with 90L... afternoon SPECIAL TROPICAL WEATHER OUTLOOK was made again... only given a 30% chance of a tropical low... Air Force Recon on standby again form a flight tmrw... heck it should be really close to AFB tmrw, i wouldn't be susprised if they flew one mission just to test out equipment/etc. The door is closing on the low now... its running out of water and time... this afternoon... a few storms have fired over center... but shear tears them apart... Close up Vis Right now over the NW Florida, there is a nice band of showers and storms along I-10. Can feel the tropical air mass up this way!
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www.Stormhunter7.com ***see my flight into Hurricane Ike ***
Wx Data: KFLPANAM23 / CW8771
2012== 23/10/9/5 sys/strms/hurr/majh
Edited by Storm Hunter (Fri May 22 2009 05:15 PM)
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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I know we are watching the low in the gulf but am wondering if the models are looking at the area of persistent rain in the Carib that has caused flooding and loss of life in Haiti this week?
Another very complicated system in the GOM and imagine after the planes go in we will have a better idea of what is really going on.
Hard to tell but if it does form.. close in there is very little time to warn anyone.
Bill Read worries on this a lot and have heard him talk at conferences where he points out most close in Gulf storms develop and hit land way under 72 hours which is the time frame we try to warn people. As they often say, a bull in the china shop even though right now it doesn't look like much of a bull.
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http://hurricaneharbor.blogspot.com/
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Hugh
Senior Storm Chaser
Reged: Fri
Posts: 1060
Loc: Okaloosa County, Florida
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Quote:
Air Force Recon on standby again form a flight tmrw... heck it should be really close to AFB tmrw, i wouldn't be susprised if they flew one mission just to test out equipment/etc. The door is closing on the low now... its running out of water and time... this afternoon... a few storms have fired over center... but shear tears them apart...
This is a bit reminiscent of T.S. Edouard that formed last year, just off the coast of Mobile. It was largley ignored by the as a non-tropical low until suddenly someone decided to send a recon out and it found to be organized enough to be a tropical depression, then strengthened to a tropical storm before moving inland. The difference with Edouard was that it was moving basically due west, while this thing is moving toward the coast. So it might very well run out of real estate, but in the post-season analysis, I would be shocked if it were not designated at least a depression.
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Hugh
Eloise (1975) - Elena and several other near misses (1985) - Erin & Opal (1995) - Ivan (2004)
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Storm Cooper
User
Reged: Sat
Posts: 1290
Loc: Panama City , FL
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You never know...... STWO...
a broad area of low pressure is centered over the gulf of mexico
about 200 miles south of pensacola florida. satellite imagery
indicates that the associated showers and thunderstorms continue to
increase this evening. additional development of this system is
possible, and a tropical depression could form before the low
moves inland over the northern gulf coast on saturday. an air
force reserve hurricane hunter aircraft will investigate the low
tomorrow, if necessary. there is a medium chance(30 to) 50
percent, of this system becoming a tropical cyclone during the
next 48 hours. regardless of development, heavy rains and
occasionally gusty winds are expected along portions of the
northern gulf coast tonight and saturday, and interests in this
area should monitor the progress of the system.
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Hurricane Season 2017 13/7/1
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cieldumort
Moderator
Reged: Mon
Posts: 2114
Loc: Austin, Tx
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Invest 90L is still running a little bit dry in 3 out of 4 quadrants, but that could end within the next 24 hours as convection keeps blowing up at least in the northeastern quad, helping to mix out the dry air still present from its days as a purely extra-tropical low.
There has been some speculation as to whether or not this system should have been re-tagged 91L. It seems like a reasonable debate, but one that is purely academic as to whether or not the feature actually becomes an officially number or named cyclone in the 2009 records.
As a matter of interesting discussion, 90L was originally identified as the mid-level cyclone near eastern Cuba which was associated with a surface trough. This feature has since become intertwined with the former extra-tropical low and associated frontal boundary which had been stalled out over Florida.
As of tonight, pressures within the surface low that is Invest 90L continue falling a bit, and persistent, deep convection continues building about its center of circulation. Winds are now running sustained above 20 knots over a fairly big area, but no doubt due in no small part to the pressure gradient from the higher pressure over the southeast, more than anything else, so far.
Due to 90L's proximity to land, it would only be reasonable for to exercise a little bit of caution and indeed send a recon out in there Saturday, if 90L has not yet improved in structure dramatically overnight, such that they would even be inclined to assign it a TC/STC number without any additional data from recon.
Regardless of whether 90L earns itself an officiated status or not, this system has a history of dumping copious rains over a large area of real estate, and now is once again partially responsible for plenty of gusty winds. Holiday plans right along and off the coast, and holiday travel in this entire area, should certainly be made with some extra consideration.
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Bloodstar
Moderator
Reged: Mon
Posts: 459
Loc: Georgia Tech
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I don't know about you folks, but I'm starting to think this storm may make it over the hump and get classified as Ana. The convection is looking better, if still lopsided, and is a (shallowish) warm core system. Bouy 42364 recorded 35kt sustained winds at 400 UTC, but that was also around 400 feet above sea level, so it's not representative of winds at the surface, even so, it's still showing some stronger winds just above the surface.
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M. S. Earth and Atmospheric Sciences, Georgia Tech - May 2020
U. Arizona PhD program starting August 2022
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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TROPICAL WEATHER DISCUSSION...UPDATED
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT FRI MAY 22 2009
...UPDATED TO INCLUDE SPECIAL FEATURE SECTION...
...SPECIAL FEATURE...
A 1007 MB SURFACE LOW IS LOCATED NEAR 27N87W...OR ABOUT 175 NM
SOUTH OF PENSACOLA FLORIDA. A SURFACE TROUGH EXTENDS FROM THE
SURFACE LOW TO THE N YUCATAN PENINSULA NEAR 21N87W. LOW LEVEL
CONVERGENCE NEAR THE SURFACE LOW AND SURFACE TROUGH...AS WELL AS
UPPER LEVEL DIFFLUENCE E OF AN ASSOCIATED UPPER LOW NEAR
28N88W...ARE SUPPORTING NUMEROUS SHOWERS AND THUNDERSTORMS
ACROSS THE GULF N OF 23N E OF 89W....INCLUDING THE COASTAL
WATERS ACROSS THE N AND E GULF. THE TIGHT SURFACE PRESSURE
GRADIENT BETWEEN THE SURFACE LOW AND A SURFACE RIDGE OVER THE SE
CONUS IS SUPPORTING WIND SPEEDS OF 20 TO 25 KT AROUND THE LOW
ACROSS N PORTIONS OF THE MIDDLE GULF. THE SURFACE LOW IS
FORECAST TO MOVE NORTHWARD DURING THE NEXT DAY AND BE LOCATED
NEAR 30N89W AS A 1008 MB SURFACE LOW AT 23/1800 UTC. ADDITIONAL
DEVELOPMENT OF THIS SYSTEM IS POSSIBLE...AND A TROPICAL
DEPRESSION COULD FORM BEFORE THE LOW MOVES INLAND OVER THE
NORTHERN GULF COAST ON SATURDAY. IF NECESSARY...AN AIR FORCE
RESERVE HURRICANE HUNTER AIRCRAFT WILL INVESTIGATE THE LOW
TOMORROW. THERE IS A MEDIUM CHANCE...30 TO 50 PERCENT...OF THIS
SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
REGARDLESS OF DEVELOPMENT...HEAVY RAINS AND OCCASIONALLY GUSTY
WINDS ARE EXPECTED ALONG PORTIONS OF THE NORTHERN GULF COAST
TONIGHT AND SATURDAY. INTERESTS IN THIS AREA SHOULD MONITOR THE
PROGRESS OF THE SYSTEM.bold emphasis added~danielw
Buoy Data
64 S DAUPHIN ISL 0445Z air73 sea74 VRB 29kt/gusts to 35kts 1005.5F 13 feet/ 8 seconds
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mbfly
Weather Guru
Reged: Mon
Posts: 118
Loc: Mobile, Alabama
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Good morning from a very soggy and windy Dauphin Island, Alabama! It has been raining heavily and steady since about 1 am . Some occasional thunder and some pretty strong wind gusts . I haven't braved going outside; just sittin' here looking out the window and watching it blow. At least I don't see Jim Cantore in my yard, so that's good!!
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JoshuaK2
Unregistered
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According to the latest AtlaOne Floater image on vis, infra, and watvap, it appears the low now has a closed off circulation, and should meet all qualifying needs to be classified as Trop Storm Ana, with 41 mph sustained winds being reported on the Alabama coastline. They shouldn't hold off on naming the thing just because it's over land now.
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Storm Hunter
Veteran Storm Chaser
Reged: Wed
Posts: 1370
Loc: Panama City Beach, Fl.
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it was close on becoming a TD... it appears that the low made landfall along the MS/Al border in the last hr. This morning a nice fired off just south of Mobile. This low was pretty close to being a TD i think.
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www.Stormhunter7.com ***see my flight into Hurricane Ike ***
Wx Data: KFLPANAM23 / CW8771
2012== 23/10/9/5 sys/strms/hurr/majh
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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The typical definition of a "closed low" is defined by Recon finding winds from at least 4 different directions nearly perpendicular to their flight path.
I.e. flying from the SW to the NE quadrant the wind would be from the NW in the SW Quad and shift to blowing from the SE in the NE Quadrant. These are rough estimates:
NW Quad = NE wind
SW Quad = NW wind
SE Quad = SW wind
NE Quad = SE wind
After flying the INVEST pattern they will make the determination of whether the Low has "closed off".
Typical patterns are the "Delta" pattern and the "Alpha" pattern. You can probably Google the NHOP and find a diagram of each pattern.
Recon flies a "leg" in one direction until the wind shifts. They then turn and fly until the next wind shift and repeat the pattern until they can " close it off"
You can use satellite imagery to some extent for closing a low. But radar and recon are much better.
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cieldumort
Moderator
Reged: Mon
Posts: 2114
Loc: Austin, Tx
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Quote:
The typical definition of a "closed low" is defined by Recon finding winds from at least 4 different directions nearly perpendicular to their flight path.
I'll take exception with the above description, as I think it is confusing and irrelevant in this situation, as recon never went into 90L. But while recon never flew 90L, the feature has pretty much been closed off for several days. Recon is helpful, if not sometimes critical, when a system is far out at sea. However, once a given feature approaches land, ground and sea-based anemometers can be clustered together in enough abundance, as to get a very clear picture of what is going on at the surface. That has been the case with 90L for at least the past 18 or so hours .
90L struggled to retain deep convection over a significant portion of its LLC. Around 2AM last night, increased their three-tiered guidance to a "High" probability of an upgrade, but by the time 5AM came around, the deepest convective flare-up with an associated MCV was back to being displaced to the LLCs northeast, after what looks to have been a brief pairing-up earlier in the overnight hours.
The same sort of situation occurred once again as 90L made landfall, with a short blast of apparent mid and low level co-location. This, too, did not fare well for long.
The wind speed/pressure relationship at the surface , closed surface low, warmer core, and other determinants do argue that 90L was riding the line, and that post-season reanalysis may deem it reasonable to include it in the official count, but as with many things, some calls are just more subjective than others.
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danielw
Moderator
Reged: Wed
Posts: 3524
Loc: Hattiesburg,MS (31.3N 89.3W)
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Closed Low
A low pressure area with a distinct center of cyclonic circulation which can be completely encircled by one or more isobars or height contour lines. The term usually is used to distinguish a low pressure area aloft from a low-pressure trough. Closed lows aloft typically are partially or completely detached from the main westerly current, and thus move relatively slowly (see Cutoff Low).
http://forecast.weather.gov/glossary.php?word=CLOSED%20LOW
A closed low has several characteristics. Closed lows tend to be deep pressure systems with one or more height contours encircling them on the analysis charts at all levels in the troposphere. A closed low is occluded and vertically stacked. Because the low is closed, it does not generate much PVA and NVA. The vort max will be near the center of rotation. It is difficult to get a windflow that produces vorticity advection because the vorticity isopleths for the most part are parallel to the height contours. The weather associated with closed lows tends to be cloudy with showers in the vicinity of the low's center. Closed lows are often slow movers but can move quickly if they are embedded within the jet stream. Cloudy and rainy weather can persist with the slow movers. Thermal advection tends to be weak with closed lows since they are occluded. A special case of the closed low is the cut-off low. A cut-off low moves slowly since the jet stream winds aloft are displaced away from the low and are thus not able to move it along.
http://www.theweatherprediction.com/habyhints/200/
closed low—A low that may be completely encircled by an isobar or contour line.
(This means an isobar or contour line of any value, not necessarily restricted to those arbitrarily chosen for the analysis of the chart.) Strictly, all lows are closed. However, in weather-map analysis terminology, this designation is used commonly in two respects: 1) on surface charts, to distinguish a low from a trough, especially as a low develops within the trough; and 2) on upper-level charts, to accentuate the fact that the circulation is closed, especially at levels and over latitudes where such an occurrence is unusual. The definition of closed high is analogous.
http://amsglossary.allenpress.com/glossary/search?id=closed-low1
http://www.google.com/search?hl=en&q="closed+Low"&aq=f&oq=&aqi=g1
Most of the Closed Low definitions require a vertically stacked system. Learn something new everyday.
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HCW
Storm Tracker
Reged: Fri
Posts: 287
Loc: Mobile,AL
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This footage was taken Right after the eyewall came onshore. Okay it wasn't an eyewall but there was no debris at all untill it made landfall and the surge came up very fast. I would estimate a good 5 FT in about 20 mins . Winds were gusting well over 50 mph at that time and we had sustained winds in the 30mph range before landfall . This storm is one that should be upgraded down the road by the and I hope that this video and some of my others will help with there decision. Problem is there is not much footage from this system but bouy data and weather station data indicate this was no doubt at least tropical depression if not a tropical storm
http://www.youtube.com/watch?v=xZohjIbwg...player_embedded
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Over 4,000 members and now on a new server
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LoisCane
Veteran Storm Chaser
Reged: Fri
Posts: 1236
Loc: South Florida
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enjoyed it alot
be interesting to see how they handle it after the season.. if at all
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http://hurricaneharbor.blogspot.com/
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mikethewreck
Weather Hobbyist
Reged: Wed
Posts: 52
Loc: Treasure Coast FL
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Any precedent in reviewing it before the season? Hopefully will be some more weeks before we get another storm.
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Earliest memory Hurricane Cleo!
Went under Hurricane Gloria!
Edited by mikethewreck (Tue May 26 2009 03:48 AM)
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metwannabe
Weather Hobbyist
Reged: Wed
Posts: 92
Loc: NC
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Nice video. I have never been to Dauphin Island and am definately no expert on what storms do to that small parcel of land, however, would seem to me that if everyday summer time storms had that type of effect they would close that road or take some major action. In other words appears to me that a small surge associated with either a strong tropical depression or even a weak TS occurred there. Will be interesting to see and I'm not sure if I have ever seen upgrades prior to season starting.
BTW any chance of the low off east coast of US being tropical? Sure looks to bring plenty of rain to the Carolinas.
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Fran, Bertha, Dennis & Floyd (Tag Team)
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HCW
Storm Tracker
Reged: Fri
Posts: 287
Loc: Mobile,AL
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I am really shocked to wake up and find out that our system off the east coast is now Invest 91L . It will have a very tough time even reaching std status and could brush the outerbanks before heading out to sea. Not bad 2 invest already and Hurricane Season is still 1 week away from starting .
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MichaelA
Weather Analyst
Reged: Thu
Posts: 914
Loc: Pinellas Park, FL
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I picked that up on sat images/loops this AM. Currently very near 30ºN;75ºW and moving @ about 315º. Very small system. SSTs are not very warm until much closer to the coast.
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Michael
WU PWS
2021 “guess:” 15/8/3
2021 Actual 21/7/4
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