Clark
Meteorologist
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Take a look at the sea surface height anomalies:
Pre-Katrina: http://www7320.nrlssc.navy.mil/hhc/watl/sha.watl.20050826.gif
Current: http://www7320.nrlssc.navy.mil/hhc/watl/sha.watl.20050919.gif
The areas of positive sea surface height anomalies are weaker and more spread out than before, albeit just barely so. They are located further north than they were, which given the expected track of the storm may keep it away from those eddies.
Also look at the hurricane heat content:
Pre-Katrina: http://www7320.nrlssc.navy.mil/hhc/watl/hh3.watl.20050826.gif
Current: http://www7320.nrlssc.navy.mil/hhc/watl/hh3.watl.20050919.gif
The erosion of the northern Gulf eddy is evident with a very small area of very high values further east of that location. I believe that the storm will pass south of this and through lower (but not negligible) areas of heat content. Overall, things are about where they should be for the Gulf for this time of year, which generally means that a major hurricane is possible, but not a monster like . I do feel that passing over the central Gulf will likely keep anything forming in the SW Gulf/Bay of Campeche that heads toward the NE from becoming a very powerful storm (but again, this could be relative).
-------------------- Current Tropical Model Output Plots
(or view them on the main page for any active Atlantic storms!)
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Random Chaos
Weather Analyst
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Posts: 1024
Loc: Maryland
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Just a quick note before I sleep:
On SSD IR, you can see 3 red cold zones. Comparing that to radar, you can see that the not-as-cold area almost centered between the three cold nodes is aligned with where the eye appears to be forming on radar. We might see an eye develop for breif periods of time on IR tonight if this trend continues.
Links:
IR: http://www.ssd.noaa.gov/PS/TROP/DATA/RT/float-ir4-loop.html
Radar: http://flhurricane.com/imageanimator.php?7
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bigpapi
Weather Watcher
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Loc: Myrtle Beach, SC
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WOW. This is the best looking TS I have ever seen. I'm still wishing the would just call it a Hurricane to ensure the folks on the Keys would take it seriously... Phillipe is a Hurricane yet looks like a wave yet is a Storm that looks like a Cane but is within striking distance of the U.S. The time for Semantics is over. I felt the same way with when she was approaching SFLA.
Edited by bigpapi (Tue Sep 20 2005 12:31 AM)
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teal61
Weather Hobbyist
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Loc: Spring, TX (30.1N 95.5W)
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FWIW, the new 00Z is coming out and through 90 hours is much further west. However at 96 hours she appears to be moving northwest. Still waiting on the rest of it to see if that northwest motion continues to landfall or a turn due north occurs as in previous runs.
Well, as I am typing this it is now out to 120 hours and the net result is about the same. Looks like after 96 hours she turns NNW and lanfalls between Matagorda and Freeport Texas. But the trek further west in the GOM delays the landfall about 18 hours or so until Saturday evening.
http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/00/index_l.shtml
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Random Chaos
Weather Analyst
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Loc: Maryland
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We aren't talking semantics. We're talking cold, hard numbers. If a storm doesn't have 75 mph winds, it isn't a hurricane. There isn't room to say "yeah, but we should call it that." Recon only found 75mph Flight Level winds...which translates to 65-70mph surface winds...under hurricane strength. Furthermore dropsound found only 60mph? surface winds. Also under hurricane strength. This thing's got an excellent satellite signature, but its winds aren't strong enough for it to be a hurricane. It's pressure is still about 10mbs higher than it needs to be for the winds to hit hurricane strength. Yeah, strengthening is expected overnight...but it stil isn't a hurricane yet.
(I think I said "isn't too many times in there )
And...dang...she looks strong on Satellite.
Night...Zzzzzzzzzzzz
--RC
Just a quick note...there is no hard and set level for hurricanes in terms of sea level pressure. There have been tropical storms with pressures <980mb, particularly over land, while there have been hurricanes with pressures of ~1000mb. The old number I used to use is 994mb, which is probably a little high. It depends partially upon the size of the storm, the external (background) pressures, the rotational aspects of the storm, and a few other balance factors; needless to say, it's not easy to calculate a true wind-pressure correlation other than the fact that as the pressure falls, the wind generally increases. --Clark
Edited by Clark (Tue Sep 20 2005 01:10 AM)
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lunkerhunter
Storm Tracker
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Posts: 248
Loc: Saint Augustine, FL
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Thanks Clark.
It would be interesting to plot to those historical temp charts and study the cause/effect.
PS - I gotta agree about the "hurricane or not a hurricane" naming semantics. You saw it with and now . Most people flunked science at somepoint in school and ignore the Warnings. If it ain't called a hurricane, people don't care. They should have called it a Cane for the 11PM to protect the greater good......my two cents.
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Margie
Senior Storm Chaser
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Posts: 1191
Loc: Twin Cities
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I think did the right thing in the 11pm: "...RITA ALMOST TO HURRICANE STRENGTH" opens the advisory. It is accurate and does get across the point that by morning will be a hurricane.
-------------------- Katrina's Surge: http://www.wunderground.com/hurricane/Katrinas_surge_contents.asp
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Brad in Miami
Storm Tracker
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Posts: 365
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I'm intrigued by the occasional strange output that is sometimes generated in the 's strike probabilities. Example in the 11pm strike probabilities: Miami's overall percentage of passing within 65 nm in the next 69 hours is 43%, which is comprised of 42% for the first 12 hours after issuance, 0% for the 24 hours after that, and then the anomoly: 1% for the 12-hour period between 8pm Wed. and 8am Thurs.
I assume this 1% chance of a "hit" that late is based on some strange model output, but it's hard for me to imagine what that scenario would look like given the current weather pattern. The most likely scenarios to produce that - both of which are nearly impossible given the current pattern - are one in which the storm stalls significantly, or another in which it sharply recurves once in the Gulf. An earlier run of one model - the CLIPER5, I believe [and hopefully I am correctly naming the model] - was a very big outlier, I believe showing a path across the upper Keys, or perhaps even the extreme SE Fla. peninsula, and then running more or less up the Florida west coast (and if this isn't clear to everyone, that scenario is incredibly unlikely; it was just one anomolous run of one model). I suppose a slight adjustment of that model, with an even sharper recurvature over SW Fla. or just offshore from there, could result in a slight chance of a Miami hit that far out from now, but that just seems like such a remote possibility - much less than 1%, I would imagine.
I'm basically just pointing out that 1% entry for anyone similarly curious about such anomolies, and to get any input from anyone who knows, or has a guess as to, where that specific one came from, i.e. on what strange and unlikely model scenario it was based.)
I realize there are much more important things to consider right now, but it's a little food for thought to keep an eye out for. There is at least one anomolous entry like that for several storms each year.
And probably a bit more important, current conditions down here in South Miami: it's absolutely beautiful outside; hopefully it will stay like this tomorrow, but of course it's likely to get worse. We've had sporadic rain: a few significant but short-lived downpours, but otherwise just light rain or none at all. We've had quite a few calm periods, but for the most part the wind has been blowing consistently in the 15-25 mph range - a beautiful breeze, keeping the heat index and/or actual temperature very comfortable - with a few gusts associated with quickly passing squalls that were probably in the 35-40 mph range. It's one of those nights that would be perfect for a walk or run if the thought of it weren't soured by the knowledge that the beautiful conditions are caused by something that's going to have an awful impact on a lot of people this week.
Best of luck to everyone potentially in the storm's path - Bahamas, Keys, extreme S. Fla., Cuba, Western/Central Gulf states, Mexico.
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danielw
Moderator
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Posts: 3527
Loc: Hattiesburg,MS (31.3N 89.3W)
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I think your Hurricane Heat content is getting a bit high there.
Rita is probably going to surprise a lot of people by sunrise. Hopefully, it will be the fact that she hasn't made Hurricane status.
On the other hand. With the prospect of intensification happening overnight.
South FL and the Keys could wake up to something they will not like to see.
Miami Beach has reported 39mph winds in the last few hours. I believe the bridges close to traffic at either 45 or 55mph.
Key West NWS office is indicating the storm surge could come at high tide. And with the Moon being one to two days from full. This would be an Astronomical High Tide.
If you live in the Keys...Get out now. Please don't wait til morning.
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danielw
Moderator
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Loc: Hattiesburg,MS (31.3N 89.3W)
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AT 11 PM EDT...0300Z...THE HURRICANE WARNING IS EXTENDED ALONG THE
FLORIDA WEST COAST FROM EAST CAPE SABLE TO CHOKOLOSKEE. A HURRICANE
WARNING IS NOW IN EFFECT FOR ALL OF THE FLORIDA KEYS...AND FROM
GOLDEN BEACH ON THE FLORIDA SOUTHEAST COAST SOUTHWARD TO EAST CAPE
SABLE THEN NORTHWARD TO CHOKOLOSKEE.
http://www.nhc.noaa.gov/text/refresh/MIATCPAT3+shtml/200245.shtml
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Hurricane Fredrick 1979
Weather Guru
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Posts: 116
Loc: Mobile,Alabama
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And look at the NGOM they got us at 7% at 11:00PM. And had us at 4% for awhile. But if it's suppose to go to TX and we are not in the cone then why are we in the probabilities? Thats why I am saying that I beleive and this IMO that it may take the NW NNW turn more sooner.
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ftlaudbob
Storm Chaser
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Posts: 829
Loc: Valladolid,Mx
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Lighting here,experts can comment on that.They can find 70mph winds but not find 74mph winds,interesting.Looks like a major band will come on shore here shortly.Looks like she is getting larger.Things will go down hill from here.The inter-coastal water ways are at a very high level,mainly due to the moon.Some branches have come down.The sharp southern turn with after it hit the coast started the non-confidence attitude with the .Winds right now are light .The local mets are now talking about the lighting,they say that means is getting stronger.
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Survived: 10 hurricanes in Rhode Island,Florida and the Yucatan of Mexico .
Edited by ftlaudbob (Tue Sep 20 2005 01:21 AM)
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Multi-Decadal Signal
Weather Guru
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Posts: 149
Loc: BROWARD
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Local Miami-Dade & Broward TV and radio stations have gone into storm mode in the past hour. WIOD & WINZ -AM stream their signal and some of the TV stations may also do so.
I'm about 10 miles North of the Miami-Dade border and thus far conditions are fairly mild. A bit of rain and a few stronger gusts but nothing much else to report.
Rita is not the one for this part of the Gold Coast...(crosses fingers)
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ftlaudbob
Storm Chaser
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Posts: 829
Loc: Valladolid,Mx
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Looking at radar,we are about to get hit by the worst weather so far.Hopfullly power will stay on,and I can report on to what is happing here.
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Survived: 10 hurricanes in Rhode Island,Florida and the Yucatan of Mexico .
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Brad in Miami
Storm Tracker
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Posts: 365
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The 4% and 7% numbers are only for the 72 hours (actually, 69 hours) after issuance of the forecast package. Your percentage likely did not go up because of any change in the forecast, but instead because you're now more likely within 3 days of the storm, i.e. the storm is closer to you. At 5 am, your percentage could go up a little more without it signifiying any change in the models or forecast track.
2 other things: First, keep in mind that's a 7% possbility of the storm's center coming within 65 nautical miles of you, not of the center passing right over you. So in other words, if the 's computer guidance and forecasters suggest a 7% chance of the storm landfalling 65 nm due west of you, you would still have that 7% chance, even if the predicts a 0% chance of it landfalling any closer than that to you. Second, that "cone" does not encompass every city with a remote possibility of close passage to the center. Some models, as well as the weather pattern that will likely exist in 2-3 days, support a slight chance of the storm heading within 65 nm of you, so therefore you still have that 7% probability.
Keep in mind 2 things: (1) 7% means it's very unlikely, so no need to worry too much; and (2) 7% means it isn't impossible, so make sure to worry just a little. And I'm kidding about making sure to worry, but definitely prepare hurricane supplies if you don't have them.
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Clark
Meteorologist
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Posts: 1710
Loc:
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The probabilities relate the chance that the center of the storm will pass within 65 miles of the region within the next 72hr. Any storm more than 2 days out is going to have a wide range of probabilities at the later periods, both in number and over a large area. Or, in other words, even for an expected perfect track forecast at 72hr, you would still see areas up to 200mi on either side of the cone listed in the probabilities.
Note that for , over 3 days from landfall, the probabilities are going to be rather low and weighted toward areas closer to the coastline along the Northern Gulf of Mexico -- like New Orleans -- and not to where the actual track takes the storm. Climatology, avg. track error, model spread, and a number of other factors go into determining these probabilities and, yes, you will see some weird results from time to time as a result of some of the factors. I wouldn't pay much attention to a 1% value, though -- it's more than likely mathematical rounding.
Simply put, the current wind product is a useful tool, but has its limitations and is rather easy to misinterpret. The is working on a new tool -- http://www.nhc.noaa.gov/text/refresh/MIAPWSAT3+shtml/DDHHMM.shtml as a current example for -- to try to better represent a storm's potential impacts, with one of the simplest improvements being that the track forecast and wind probabilities now both go to 5 days apiece. In this product, as of 11p Monday, Galveston, TX has the highest probability at 44% for cities in terms of the second landfall. But, you see some non-zero probabilities for other areas, just in case the storm does something unexpected.
Look at it this way: I don't believe the storm has a shot to impact Tallahassee, where I am located. But, say the unexpected were to occur and it turned northward. There is precedent for something like that, it is within the realm of accumulated track error (not for one forecast, but a series of them), and thus you see a non-zero porbability (here, 7%). A similar interpretation can be applied to the older product, just keeping in mind the limitations inherent to any such product.
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danielw
Moderator
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Posts: 3527
Loc: Hattiesburg,MS (31.3N 89.3W)
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URNT12 KNHC 200547
VORTEX DATA MESSAGE
A. 20/05:22:30Z
B. 23 deg 32 min N
078 deg 37 min W
C. 700 mb 3031 m
D. NA kt
E. deg nm
F. 053 deg 064 kt
G. 315 deg 044 nm
H. 991 mb down 1 mb since last Vortex~danielw
I. 9 C/ 3040 m
J. 13 C/ 3042 m
K. 8 C/ NA
L. NA
M. NA
N. 12345/ 7
O. 0.02 / 3 nm
P. AF304 0818A OB 19
MAX FL WIND 72 KT NE QUAD 03:54:00 Z
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ftlaudbob
Storm Chaser
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Posts: 829
Loc: Valladolid,Mx
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Clark,I am getting lighting here,is it true that means a storm getting stronger?Rita the greatest tropical storm that ever lived!!!!
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Survived: 10 hurricanes in Rhode Island,Florida and the Yucatan of Mexico .
Edited by ftlaudbob (Tue Sep 20 2005 02:04 AM)
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Clark
Meteorologist
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Posts: 1710
Loc:
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Lightning and tropical cyclone strength/intensity are not very well correlated. Lightning activity deals with charge separation and ice content; perhaps with very cold cloud tops (e.g. a greater amount of ice -- note that it takes temperatures to -40C before all water in the upper atmosphere is frozen; the reasoning behind that is best saved for another day) you could be seeing a bit more lightning, but otherwise intensity change and lightning aren't very well correlated.
-------------------- Current Tropical Model Output Plots
(or view them on the main page for any active Atlantic storms!)
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Tazmanian93
Weather Master
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Posts: 495
Loc: Tampa
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I know @ the 11, the clouds tops were very cold @ -80 so at that time def getting stronger
-------------------- Don't knock the weather; nine-tenths of the people couldn't start a conversation if it didn't change once in a while.
Go Bucs!!!!!!!!!
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Ed
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