MikeC
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| (Admin) |
| Sat Sep 01 2007 11:49 AM |
Hurricane Felix forms in Southeastern Caribbean
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7:45 PM EDT Update 1 Sep 2007
Hurricane Felix has formed in the southeastern Caribbean. Recon found the storm's center slightly south of the 5PM position, so the further west track continues. Those in Aruba should take note of that. Beyond that, Honduras.
7:40 PM EDT Update 1 Sep 2007
Aircraft recon just reported a 993mb pressure in Felix, it's extremely likely it will be a hurricane at the 8PM advisory.
7PM EDT Update 1 Sep 2007
Felix is now just shy of hurricane strength right now, and may become a hurricane later tonight as it moves westward. In fact Recon just found 66knot surface winds, which puts it over hurricane threshold, so Hurricane Felix may be recognized as early as 8PM.
Model initializations have been a bit off, but it still looks like the National Hurricane Center's forecast track will hold. The thinking here still takes it south, with Honduras coming precariously close.
We'll be watching.
1PM EDT Update 1 Sep 2007
Despite proximity to South America, Felix has strengthening during the day and could become a hurricane tonight or tomorrow.
Once it clears the tip of South America, conditions are favorable for Felix to become a major hurricane. Which, the National Hurricane Center forecasts it to do. It will pass close enough to the Netherlands Antilles and Aruba to potentially bring tropical Storm Force winds to those islands.
Beyond that depending on trends, those in Northern coastal Nicaragua and Honduras need to watch it around Tuesday, as the forecast track takes it very close offshore north to there, and beyond that Belize and the Yucatan of Mexico around Wednesday or Thursday.
98L, in the Central Atlantic, slightly north of and mostly east of Felix, is persisting quite well and is on track to become a depression within the next few days. Those in the Lesser Antilles of the Caribbean, on the north side, including Puerto Rico and the Virgin Islands will want to keep an eye out on 98L. This one is a bit further north, long range, it has more potential to affect the US than the other systems, but still plenty of time to watch trends on that one.
Chances for Tropical Development of Central Atlantic Wave off Africa (98L) In Next 3 days
Code:
(forget it) 0 1 2 3 4 5 6 7 8 9 10 (sure thing)
[------------*-------]
It has the potential, if it persists, to become the season's 7th classified tropical system sometime over the holiday weekend.
Original Update
Tropical Storm Felix has formed from Tropical Depression Six in the southeastern Caribbean, it's moving generally west, and is looking a little ragged, perhaps due to the proximity to South America. It will move westward and pass just north of the Netherlands Antilles including Aruba as it moves to the west.
Close enough for Tropical Storm Warnings to be issued for those islands and parts of the Northern Venezuelan coastline.
It's not expected to strengthen all that much today, but may later on as it moves further away from South America.
The hurricane center's track is again, pretty straightforward, at least for the next 3 or four days. Mostly west, or slightly north of due west, making it possible to clip Nicaragua and Honduras--but staying just north---and eventually head more west into Belize. There are no signs of a potential north turn, in fact if anything it may stay further south. This is due to a high in the Gulf of Mexico that will strengthen the ridging in the area driving the storm even further west. The hurricane center's forecast track is to the south of some models however. The hurricane center's forecast track looks pretty good.
We'll be watching, though, some models have trended more north, but these models are already too far north for the current position of the system.
Beyond Felix a wave further east in the Atlantic, being referred to as 98L will have to be watched over the coming days.
Netherland Antilles/Aruba Radar 1
Netherland Antilles/Aruba Radar 2
{{StormCarib}}
{{StormLinks|Felix|06|6|2007|1|Tropical Storm Felix}}
{{StormLinks|98L|98|7|2007|2|98L (East Atlantic Wave)}}
| CoconutCandy |
| (User) |
| Sat Sep 01 2007 11:55 AM |
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Enter Felix, Stage Right
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Good Morning All. TD-6 has been upgraded to Tropical Storm Felix at the 5am advisory.
From NHC's 5am discussion #3:
"THE CONVECTIVE PATTERN OF THE CYCLONE HAS CONSOLIDATED SOMEWHAT OVERNIGHT...WITH THE COLDEST CLOUD TOPS NOW FOCUSED ON A CLUSTER VERY NEAR THE ESTIMATED LOW-LEVEL CENTER LOCATION ... AND THE ADVISORY INTENSITY IS RAISED TO 35 KT ... SO THE DEPRESSION IS UPGRADED TO TROPICAL STORM FELIX."
Felix is still very much in the formative stages and is still in the process of consolidating, but the deep convection continues to expand with continuing organization of the feeder bands, several of which are now in evidence in the western semi-circle, with more beginning to take shape in the SE quad and the northern periphery.
Also, the deep convection has maintained very cold cloud top temps of -70 to -80, all the while continuing to organize better, implying that gradual intensification is underway. And upper level outflow is quite good and only improving.
First visible satellite images suggest, from a steadily improving satellite signature, that Felix is beginning to strengthen in earnest, as it traverses the ever-warmer waters of the Caribbean ahead of it. Although not an especially large system, I surmise that Felix will continue to steadily expand its' wind field, and could easily become much larger before making landfall.
University of Hawaii Weather Server version of Tropical Satellite Imagery:
http://weather.hawaii.edu/satellite/sata...amp;overlay=off
(I like to click the 'Rock' button for a back-and-forth effect and slow it down just a tad.)
Moving a little faster now, it seems that Felix is destined to be, like Dean, a 'Straight Shooter' type system, with high confidence in taking it directly towards Central America, with a possible landfall in Belize nearing Cat 3 strength.
Shear is expected to remain low to non-existent, so an even stronger hurricane wouldn't be out of the question by the end of the forecast period. Remember that mid and long range *intensity forecasts* have a much greater degree of error than do those regarding location, and all environmental factors appear to be favorable, certainly not inhibitive, once Felix pulls away from Venezuela and is able to more easily expand its' wind field and overall circulation envelope.
All in all, it would appear that Felix could become a quite 'respectable' Caribbean Hurricane, which fortunately, should not effect US interests.
| Random Chaos |
| (Weather Analyst) |
| Sat Sep 01 2007 12:37 PM |
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Re: Enter Felix, Stage Right
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NRL has just put up a new invest, 98L. Not much info on it now, but the satellite visible is at about 38W 14N.
Edit:
Checking the models, only the MM5 (mm5fsu45a and mm5fsu45b) are picking up on 98L at all, and very weakly.
These same MM5 models are showing Felix taking a track into the Gulf - definitely can't write Felix off as a Central American storm yet.
Also, looking through the models shows something fairly big developing out of HENRIETTE in the pacific just off Baja California in the next couple days. It's not Atlantic, but the track takes it up toward Arizona and California, and all the major models are showing it (MM5, GFS, NOGAPS, and CMC). Edit: Looking through more models, most are taking it into Baja California as a weak hurricane with precip overspeading the southwestern US, but a couple, including the GFDI and SHIPS bring the system up to major hurricane status. Arizona, California, and New Mexico need to watch this one. See http://euler.atmos.colostate.edu/~vigh/guidance/
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danielw
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| (Moderator) |
| Sat Sep 01 2007 01:05 PM |
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Recon
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Apparent problems with one of the Recon flights this morning. Departed for Felix and were airborne about 60 minutes.
Highest measured wind speed at flight level was 38 knots. First aircraft has since turned back north bound and I didn't see any lat/ longs near the storm center per the NHC/ TPC coordinates.
Second aircraft was still on the ground at last check, but appeared to be ready for takeoff.
I may have missed some of the data, but I checked it 2 or 3 times.
Meanwhile. The buoy reports from the Eastern Cribbean aren't indicating any real changes. With an exception to the wind gusts at the far Eastern Caribbean buoy. Pressure was just above sea level pressure or around 29.95 in Hg.
http://www.ndbc.noaa.gov/station_page.php?station=42059
| Beaumont, TX |
| (Storm Tracker) |
| Sat Sep 01 2007 02:30 PM |
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Re: Enter Felix, Stage Right
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Is this the one that NHC mentioned in the tropical weather outlook, the one that looks like it is following Felix but further north?
Looks like it has some increased shower activity (can see this on the satellite picture). Any chance of development in the future on this one?
| Beaumont, TX |
| (Storm Tracker) |
| Sat Sep 01 2007 02:38 PM |
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Re: Recon
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Just looked at the model plots of 98L. It is the one where showers are noticeable on satellite this morning.
Wonder if it will hang on like Felix did and slowly develop.
| nicaragua |
| (Registered User) |
| Sat Sep 01 2007 02:54 PM |
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Re: Tropical Storm Felix forms in Southeastern Caribbean
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IT LOOKS LIKE THE HIGH PRESSURE RIDGE IS MOVING WITH FELIX AND ALSO BUILDING AHEAD OF FELIX.
UNLESS SOMETHING CHANGES, THE TRACK WILL BE MORE SOUTH. IN NICARAGUA WE GET VERY LITTLE INFORMATION. ANY INFORMATION FROM ANY OF YOU WILL HELP US A LOT.
| Random Chaos |
| (Weather Analyst) |
| Sat Sep 01 2007 03:32 PM |
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Re: Recon
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11AM NHC said that Felix had a tightly wound core. You can make that out very well on Microwave from NRL:
Microwave Link
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sat Sep 01 2007 05:32 PM |
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Re: Recon
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thought this was interesting, the UCF damage impact model plot (Experimental) made a jump to the north some... Recon just went through a bit ago.. and winds were stronger on outbound it looks like....Flt. Level winds From 115° at 64 knots (From the ESE at ~ 73.6 mph) at 17:15:00Z at 12.73N 64.27W....at an alt. of 345 meters (~ 1,132 feet).... think i saw a pressure of 998mb....
**Vortex has pressure of 999mb... MAX FL WND OUTBOUND FROM CNTR 70KTS @ 17:14:00Z***
| punkyg |
| (Weather Watcher) |
| Sat Sep 01 2007 05:42 PM |
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Re: Recon
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Is Felix nearing hurricane strength right now or has he made achieved hurricane status.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sat Sep 01 2007 05:52 PM |
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Re: Recon
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Quote:
Is Felix nearing hurricane strength right now or has he made achieved hurricane status.
the 2pm just came out... winds up to 70mph and 999mb
"200 PM AST SAT SEP 01 2007
...FELIX NEARING HURRICANE STRENGTH..."
| BillD |
| (User) |
| Sat Sep 01 2007 05:52 PM |
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Re: Recon
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From the 2:00 PM intermediate advisory:
DATA FROM THE STEPPED FREQUENCY MICROWAVE RADIOMETER ON BOARD THE
AIR FORCE RESERVE HURRICANE HUNTER INDICATE THAT MAXIMUM SUSTAINED
WINDS HAVE INCREASED TO NEAR 70 MPH...110 KM/HR...WITH HIGHER
GUSTS. FELIX COULD BECOME A HURRICANE LATER TONIGHT OR ON SUNDAY.
Not a hurricane, yet.
Bill
| dem05 |
| (User) |
| Sat Sep 01 2007 05:56 PM |
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Re: Recon
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Well, I wonder if there may be one other fly in the ointment. The models have had a fair amount of difficulty in identifying areas of cyclogenesis here. Before yesterday afternoon, none of the major models showed the development of Felix...If 98L ends up becoming TD7, then the models will be building a bit of a recent track record here for not calling systems pre-development...As I really do not see any of the major models making much of 98L right now.
Only being that it is September, it is worth mention that there is another tropical wave gaining thunderstorm activity. That is the wave south of Jamaica. The organization/structure of the system is nothing to write home about. However, it will be curious to see if the thunderstorm activity that has been building in that area continues with some persistance over time. At this time, there seems to be little/no representation of this wave in the models...yet then again, this wave is in the very same favorable waters of the Carribean...and is far enough from Felix to be of note. Don't get me wrong, I'm not calling for any development here, but it would be curious to see if a well defined wave may imply some additional steering effects on Felix from upstream. Time will only tell...
Carribean visible loop: http://www.ssd.noaa.gov/goes/east/carb/loop-vis.html
| stevie |
| (Verified CFHC User) |
| Sat Sep 01 2007 06:09 PM |
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Re: Recon
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None of the models were picking up on Felix or 98-L yesterday and I don't see anything picking up on the area near Freeport Texas either. Local Mets are talking about it as a broad Low and Dr. Lyons mentioned it this Saturday morning. These things generally take time to develop but pressures had been lowering during the morning hours. It will be interesting to see if the thunderstorms continue to persist here as well.
| Beaumont, TX |
| (Storm Tracker) |
| Sat Sep 01 2007 06:22 PM |
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Re: Recon
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You know, the models are good. They certainly help with track and intensity. But there is something to be said for experts who have watched
these storms for years and know the trends. A "person" who knows the tropics might pick up on and recognize things before the models pick
up on it. Take for instance, Felix. The NHC kept mentioning him in its tropical update even though the models gave him no support.
That's one you could just look at on the satellite view and say "hey, there is a chance there". Models just aren't good enough yet, and people
have brains that actually "think". So, while the models are an excellent tool it takes the people who know these storms,
like those at the NHC, to bring all the information together to come up with a reliable forecast.
| hurricaneguy |
| (Weather Hobbyist) |
| Sat Sep 01 2007 06:42 PM |
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Re: Recon
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Wow lets not jump the guns just yet. True models have been shifting lately but most of the more reliable ones have stayed consistent with a Belize/Yucatan landfall. Like with Dean, the models will continue to jump around a lot but most agree that the high will hold and keep Felix heading were big brother Dean did. As for 98l I expect it to struggle for a while but I think it has a chance to get going in a few days once it passes the dry air and 20kt wind shear.
| Wxwatcher2 |
| (Storm Tracker) |
| Sat Sep 01 2007 07:34 PM |
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Re: Recon
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I usually leave comments for the pro's here on the forum. I think the mod's like it that way.
This forum used to be a place to banter about ideas and thoughts but now it's not that.
SO, I don't comment as much. I wanted to say that it looks as if Felix will indeed take a Southerly path
and affect the Southern Carribean and not turn too far North.
I trust the models. Realizing that they can and do change somewhat. What I do notice is that for every storm,
there are those that wishcast a storm to enter the gulf and threaten the U.S. coast.
Make no mistake, the U.S and the Gulf coast states get their share of storms but be careful about
comments that turn a storm Northward when the weather data does not back that up.
2004 and 2005 were historicly busy seasons. We are now back into a more normal pattern of storms.
I am thankful for that. We all should be.
| craigm |
| (Storm Tracker) |
| Sat Sep 01 2007 07:56 PM |
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Re: Recon
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Couldn't agree more. I would rather talk, or more correctly, read about the synoptics that could influence the steering mechanisms on a storm rather than conjecture about what the models will or won,t do. We all know beyond 3-5 days the margin of error becomes huge. Models are predicting what a fluid inside a fluid will do and there are just too many variables. I only look at 3 days out with great confidence.
| dem05 |
| (User) |
| Sat Sep 01 2007 08:04 PM |
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Re: Recon
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I'd also like to pitch in here. The models do generally favor a path toward Belize or the Yucatan portion Mexico. Toward the end of the guidance package, there is a sizable split between a storm approaching the Yucatan on a westward course, or a NW ward course. Only time will trimline the day 4and 5 in the models into some better agreement.
As forthe NAM Model. It does insist on pulling Felix north. With that said, the NAM is not considered one of the reliable hurricane forecast models...
...With that said, the NWS Tallahassee office has included the reasoning for why the NAM wants to pull Felix north...I don't feel the NAM has pulled it down correctly, but model was worthy of mention in Tallahassee Area Forecast Discussion, so it can't be totally discounted either.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
230 PM EDT SAT SEP 1 2007
Exerpt from Short term forecast:
ON MONDAY...THE NAM DEEPENS THE TROUGH OFF THE SOUTHEAST U.S. COAST
SLIGHTLY...WHICH IN TURN AFFECTS THE PATH OF FELIX. THE NAM
SHOWS A WEAK RIDGE IN OUR AREA WITH SLIGHTLY DRYER AIR EXTENDING DOWN
INTO NE GEORGIA. THE GFS SOLUTION IS DIFFERENT. LOW OFF THE GEORGIA
COAST. STRONGER RIDGE IN THE GULF OF MEXICO. MUCH DRYER AIR IN
OUR AREA. THERE IS LESS OF A CONNECTION BETWEEN TROUGH IN THE
SOUTHWEST U.S. AND TROUGH IN THE SOUTHEAST. THE GFS SHOWS NO
CONNECTION BETWEEN FELIX AND TROUGH OFF THE EASTCOAST OF US. EAST-
WEST RIDGE AXIS BLOCKS ANY CONNECTION.
TUESDAY...THE NAM DEPICTS THE TROUGH OFF THE EASTCOAST AND THE
ASSOCIATED WEAKNESS IN THE RIDGE AXIS REALLY AFFECTS THE PATH OF
FELIX DRAWING IT FARTHER NORTHWARD. WESTERN RIDGE BECOMES ELONGATED
EXTENDING MORE EASTWARD AND MOVES OVER THE TOP OF THE TROUGH IN TEXAS
BRINGING ADDITIONAL DRY AIR INTO THE SOUTHEAST. TIMING IS THE
QUESTION...THE GFS SHOWS THE TROUGH OFF THE EASTCOAST
FINALLY BEGINNING TO DEEPEN...WITH NO CONNECTION TO FELIX. UPPER HIGH
CONTINUES TO MOVE WESTWARD NOW CENTERED IN THE WESTERN GULF OF
MEXICO.
THE GFS DROPS THE POPS ON MONDAY TO 10 PERCENT WEST TO 36 PERCENT
SOUTHEAST. HAVE PRETTY MUCH GONE WITH CLIMO ON MONDAY...SOMEWHAT IN
BETWEEN THE NAM AND GFS. I HAVE MAINTAINED THE TEMPS THROUGH THE
PERIOD AS SUGGESTED BY GFS AND MAV.
.LONG TERM...ALTHOUGH IT MAY BE A VERY SLOW PROCESS...EXPECT POPS TO
GRADUALLY RETURN TO NEAR OR JUST ABOVE CLIMO LEVELS BY THE END OF
THE PERIOD...AS THE DEEP LAYER MOISTURE EVER SO SLOWLY RELINQUISHES
ITS HOLD OVER THE SE U.S. THE UPPER LEVEL PATTERN WILL REMAIN VERY
WEAK AND COMPLEX THROUGH THE PERIOD...AND ANY SLIGHT CHANGES TO IT
COULD HAVE DRAMATIC RESULTS ACROSS OUR REGION OVER THE MID-WEEK TIME
FRAME...BUT AT THIS TIME...THE PUSH TO REMOVE THE TRAPPED TROPICAL
MOISTURE APPEARS TO BE SLOW AND WEAK AT BEST.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sat Sep 01 2007 08:53 PM |
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Re: Recon
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well, 5pm leaves a few questions... seems a few models like HWRF, etc. leave NHC wondering... but the track was slightly shifted to the north... looks like its going to come down, what will happen with the high in the GOM... will it stayed centered in GOM, or move to the east some? Sounds like to me, that NOAA9 might be schedule to fly in GOM/Western Carb in a few days?
THE FORECAST HINGES ON HOW STRONG THE RIDGE
REMAINS OVER THE GULF OF MEXICO. THE UKMET/NOGAPS/GFDL/HWRF ALLOWS
A HIGH OVER THE CENTRAL GULF COAST TO SHIFT EASTWARD NEAR FLORIDA
AND CAUSES A MORE NORTHWESTWARD TRACK OF FELIX IN ABOUT 5 DAYS.
HOWEVER...THE GFS/ECMWF KEEP THE RIDGE IN PLACE AND MAINTAIN FELIX
ON A WEST OR WEST-NORTHWESTWARD MOTION.
| Random Chaos |
| (Weather Analyst) |
| Sat Sep 01 2007 09:01 PM |
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Re: Recon
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Well, I know that the NHC has been using the HWRF all year, but I have to say that with every storm this year the HWRF has been consistently underdeveloping them. Dean it kept as a TS or a Cat 1 for ever, and then after Dean reached Category 2 and 3 it kept calling for Dean to weaken. I'm not sure if this is an issue with initiation conditions with HWRF, or if it simply isn't that good with hurricanes. As it is a new model, I'm sure we will hear something about its poor track record in post season analysis.
| Clark |
| (Meteorologist) |
| Sat Sep 01 2007 09:26 PM |
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Re: Tropical Storm Felix forms in Southeastern Caribbean
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Felix is getting its act together today; as it nears that warm oceanic eddy south of Haiti, I expect we'll see more significant strengthening (assuming it doesn't occur sooner). NHC intensity forecast is conservative if anything at this point. Track forecast looks good as of now; remember, the models are prone to shifts back and forth at 4-5 days. We saw this with Dean and we're seeing it with Felix now. There may be a bit more significant signs of a weaker ridge across the southeast/Gulf of Mexico this time around, but the southerly route is still the most likely one.
Having said that and before moving on to 98L, just a brief reminder about the rules: discussion back and forth about the storms is fine; wishcasting or unsupported hyperbole is not. 99% of the time there's not a problem, just trying to nip things in the nub before they (might) become a concern.
98L is one of those that will likely be near the cusp of depression status sometime this weekend, likely as it nears 50W. There's more concrete discussion on this one in the Storm Forum, so I'm going to be brief here. It's starting further north than other recent features, making its potential track more uncertain. Right now, it's still being sheared somewhat from the east, and coupled with some dry air and marginal SSTs, expect slow organization for now.
Frontal low near Bermuda looks as good right now as Chantal and Barry did, but it's headed out to sea and is likely non-tropical thermally-speaking at this time. It might get a passing look in post-season analysis, given the mentions of the storm in the Tropical Weather Outlooks, but that's probably it for that one.
After Felix and 98L, the next one in line is about to come off of the African coast...and on and on from there. It's Cape Verde season, and it's here for September.
| weather999 |
| (Weather Watcher) |
| Sat Sep 01 2007 10:05 PM |
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Re: Tropical Storm Felix forms in Southeastern Caribbean
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000
URNT12 KWBC 012139
VORTEX DATA MESSAGE
A. 1/2125Z
B. 12 DEG 28 MIN N
65 DEG 23 MIN W
C. NA
D. NA
E. NA
F. 043 DEG 57 KT
G. 300 DEG 18 NM
H. 996 MB
I. 13 C/2456 M
J. 14 C/2420 M
K. 14 C/NA
L. POORLY DEFINED
M. NA
N. 12345/NA
O. 1/1 NM
P. NOAA2 0506A FELIX OB 05
MAX FL WIND 57 KT NW QUAD 2119Z
EYE WALL APPEARS TO BE FORMING SW - SE SIDE
I believe this is new recon, if it's not, ill delete post.
Looks like a hurricane to me just looking at satellite images-looking at vis/ir4, the "eyewall" forming seems to be occuring.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sat Sep 01 2007 10:50 PM |
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Re: Tropical Storm Felix forms in Southeastern Caribbean
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i think you are correct... the old kermit the frog (N42RF) is out there... Miss Piggy will be out later tonight. These P-3's are getting good research data for HRD. at last check, At 22:44:30Z (last observation), the observation was 146 miles (235 km) to the NNE (28°) from Caracas, Venezuela... for N42RF or NOAA2... there flying to the SW at about 8,000ft
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danielw
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| (Moderator) |
| Sat Sep 01 2007 11:06 PM |
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HRD Recon
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HRD just made a pass through the center and it looks like they may upgrade Felix to a Hurricane at the next advisory.
(124deg at 064kts-flt level 065kts average 063kts SFMR-surface wind speed estimate~danielw)
124064 065 063
127071 075 064
127064 075 066
Central pressure on the EYE/ Center dropsonde was 993mb.
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danielw
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| (Moderator) |
| Sat Sep 01 2007 11:36 PM |
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Re: HRD Recon
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URNT12 KNHC 012335
VORTEX DATA MESSAGE AL042007
A. 01/2241Z
B. 12 DEG 29 MIN N
65 DEG 43 MIN W
C. NA
D. NA
E. NA
F. 129 DEG 77 KTS
G. 050 DEG 14 NM
H. 993 MB
I. 16 C/ 2423 M
J. 17 C/ 2450 M
K. 14 C/ NA
L. OPEN NE
M. C30
N. 12345/7NA
O. 1/2 NM
P. N0AA2 0506A FELIX OB 09
MAX FL WIND 77 KT NE QUAD 2238Z
| punkyg |
| (Weather Watcher) |
| Sun Sep 02 2007 12:30 AM |
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Re: HRD Recon
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Will the wave in front of Felix effect him an any way?
| Clark |
| (Meteorologist) |
| Sun Sep 02 2007 12:43 AM |
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Re: HRD Recon
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Quote:
Will the wave in front of Felix effect him an any way?
No, it is not likely to do so. Generally mid- and upper-level features are the ones that steer significant tropical systems, not low-level features such as tropical waves. It appears as though Felix will remain south a ridge of high pressure and steered to the west or west-northwest over the next few days.
| CoconutCandy |
| (User) |
| Sun Sep 02 2007 01:38 AM |
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Felix Quickly Attains Hurricane Strength
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Wow. I've been away for the day and look what's happened. Felix becomes a Hurricane!
I was speculating in my last post that Felix appeared to be steadily intensifying, just from it's ever improving satellite signature and noticing an increase in the extent and amount and organinzation of it's developing rainband structures, coupled with it's highly favorable thermodynamic environment and steadily improving outflow.
Additionally, the inner core convection has remained quite deep and tightly wound for at least the last day, and an eyewall feature has finally emerged, as Felix has matured into a hurricane remarkably fast. As in 27 hours fast!
Remember. The little invest which mushroomed into TD-6 occured just 2 nights ago, during the diurnal convective maximum cycle. And, as was widely posted, the invest could well have been at TD strength well before the Hurricane Hunters arrived on the scene and confirmed with instrumentation and sensors the fact that bonafide cyclogenesis had indeed occured.
So the first advisory on TD-6 went up at 5pm EDT Friday. And now, as of 8pm EDT Saturday, we have Hurricane Felix. From Depression to Hurricane in 27 Hours!
During this period, central pressures have dropped from 1008mb to 993mb, a drop of only 15mb, or an average of about a half-millibar per hour. And I don't think that quite meets the criteria for the definition of 'Explosive Intensification' of a tropical cyclone, and I'll look for that info and add it into the post later.
But even giving, say, a day and a half - the past 36 hours from now - we've went from just another little ho-hum invest that *none* of the global models were picking up on, let alone prognosticating a full-blown hurricane in a mere 36 hours, to a now fully developed Classic Caribbean Hurricane.
And judging from Felix's already rather potent appearance, which only steadily continues to improve, I'd underscore my previous thinking that Felix may very well become a Major Hurricane, and sooner rather than later.
-----------------------------------------
>> Shear is expected to remain low to non-existent, so an even stronger hurricane wouldn't be out of the question by the end of the forecast period.
>>Remember that mid and long range *intensity forecasts* have a much greater degree of error than do those regarding location, and all environmental factors appear to be favorable, once Felix pulls away from Venezuela and is able to more easily expand its wind field and overall circulation envelope.
------------------------------------------
And, since that last post, it has indeed greatly expanded it's wind field and the extent of its circulation envelope, with it's rapidly developing, far-flung outer rainbands beginning to give this storm a much larger appearance.
We'll see what becomes of the pressure falls over the next day or two, and see if the criteria for 'Explosive Deepening' is attained and just how massive and potent Felix will eventually become. It certainly has all the earmarks of becoming a 'Dangerous Force' with which to contend.
And a slightly more northward track would certainly put much beloved Jamaica 'under the gun', again, where a TS Watch is already in effect.
It's certainly beginning to look like Felix could continue to evolve, and quite rapidly, into a very potent Classic Caribbean Hurricane. Let's just hope the ridging holds firm and keeps him far south of Jamaica and US Interests.
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MikeC
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| (Admin) |
| Sun Sep 02 2007 01:50 AM |
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Re: Recon
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My concerns right now are for Aruba, Bonaire, and the Netherlands Antilles. Felix is still moving due west and it hasn't cleared that latitude yet. The wind field on Felix is beginning to expand, and parts of those islands should probably be under a Hurricane Watch or warning if the westward movement continues. I have friends in Aruba and I have let them know about it already.
Beyond that, I still think Felix will stay further south, affecting Honduras. I hope nothing like Mitch did in 1998, but it could be, although Mitch was a slow mover. The coastline Felix is projected to near in Honduras is very vulnerable to mudslides and the like.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sun Sep 02 2007 01:55 AM |
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Re: Recon
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Hey Mike, could you record the radar images for a longer loop... there's only about 6 images in the current setup on the front page links. Looks more west, but its hard to tell with only six images... Eye is showing up nicely though
| Random Chaos |
| (Weather Analyst) |
| Sun Sep 02 2007 02:24 AM |
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Re: Recon
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I hope not a Mitch repeat
System is forming further east and is moving faster than Mitch. Unless it slows down and eventually stalls, it won't be a Mitch.
For the record, Mitch:
Unisys track: http://weather.unisys.com/hurricane/atlantic/1998/MITCH/track.gif
NHC analysis: http://www.nhc.noaa.gov/1998mitch.html
Atlantic tracks for 1998: http://www.solar.ifa.hawaii.edu/Tropical/GifArchive/atl1998.gif
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sun Sep 02 2007 02:58 AM |
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Re: Recon
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Well he is moving west now at about 18mph...
1100 PM AST SAT SEP 01 2007
...CENTER OF FELIX MOVING WESTWARD...LIKELY TO PASS JUST NORTH OF
BONAIRE...CURACAO...AND ARUBA ON SUNDAY...
Will be able to follow it on radar for another 12-24 hrs..... Looks to pass close to Aruba.
| BillD |
| (User) |
| Sun Sep 02 2007 03:05 AM |
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Re: Recon
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Quote:The link on the main page points directly at the Dutch Antilles weather website. I was in the process of writing a script to pull periodic radar images (what Mike does when he sets up custom radar loops for this site) and the entire site stopped responding, probably because it got overwhelmed with hits. It is too bad that someone can't get all these smaller weather sites linked into some common distribution method so that they don't get knocked offline when things like this happen.
Hey Mike, could you record the radar images for a longer loop... there's only about 6 images in the current setup on the front page links. Looks more west, but its hard to tell with only six images... Eye is showing up nicely though
Bill
| Random Chaos |
| (Weather Analyst) |
| Sun Sep 02 2007 03:12 AM |
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Re: Recon
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Not to worry anyone, but this caught my eye in the NHC discussion on Felix:
"THE
RAPID INTENSITY INDEX ATTACHED TO THE SHIPS MODEL CONTINUES TO CALL
FOR A 30-40 PERCENT CHANCE OF RAPID INTENSIFICATION...SO IT WOULD
NOT BE SURPRISING IF FELIX WAS STRONGER THAN FORECAST BY 72 HR.
THE INTENSITY FORECAST AFTER 72 HR MAY BE DEPENDENT ON A
COMBINATION OF LAND INTERACTION AND EYEWALL REPLACEMENT CYCLES..."
| Texas Cane Tracker |
| (Verified CFHC User) |
| Sun Sep 02 2007 03:28 AM |
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Re: Recon
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Can someone please tell me where I can see a visual of a ridge, and explain to me what to look for?
Thanks.
| flahurricane |
| (Weather Hobbyist) |
| Sun Sep 02 2007 03:35 AM |
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Re: Recon
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What are your opinions of the ridge thats moving into the Gulf? How strong will it be and how long will it continue to keep Felix on a westerly track?
| typhoon_tip |
| (Meteorologist) |
| Sun Sep 02 2007 05:08 AM |
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Re: Recon
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Quote:
What are your opinions of the ridge thats moving into the Gulf? How strong will it be and how long will it continue to keep Felix on a westerly track?
I refer you to post #77637 in "Tropical Depression #6 Forms East of Caribbean"
The southern routes are the most likely. But, this is not absolute, either, anomalies relative to anomalies happen occasionally. But for now, I think this is just like what took place with Dean when it, too, was in this lat/lon. There was all kinds of tough-to-refute reasons why it would turn N... But, there is an on-going anomally in the global atmospheric angular momentum, that is predominently negative -- particularly at these lower latitudes, which correlates to longitudinal bias, not recurvers.
I bet this is BOC bound. After that, Mexico.
| cieldumort |
| (Moderator) |
| Sun Sep 02 2007 05:26 AM |
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Re: Tropical Storm Felix forms in Southeastern Caribbean
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Both key players (Felix & Henriette) tonight are doing nothing but improving their internal structures, while concurrently their respective environments improve, as well. Given these trends, hitting overnight convective maxes, and upcoming warm eddies (esp. for Felix) it's not difficult to buy into the figures coming out of the SHIPS Rapid Intensity Indexes.
Other recent systems - 96L looked about as good as a highly-sheared tropical storm as I've usually followed. Wouldn't be surprised if someone pipes up about giving it a second look when the season is done. Surprisingly-untagged is the feature now near 34N 60W, as Clark notes - looking as good as Barry or Chantal of earlier this season. (Just not as much a threat to land, if at all) Also, can't find any nearby obs from that area, and it has already begun melding with the approaching front.
Front draped across the south and which rides up the Ga/Sc coast needs to be watched for the potential of something bubbling up along it over the course of the next couple of days. Anything which might be able to develop along it.. (just offshore) ... could be a boomerang back at the states.
Plenty insight shared on 98L already, and I don't have much to add to it, other than I am wondering if it might be starting out *just* north enough to get looped back out to sea from the ULL currently centered around 25N 55W, and which has been digging in a little bit south of that tonight. There has been some hint of a trend for 98's convection to refire progressively north of wherever it fired up last, and might begin to be a case of chasing the deep convection.. progressively northbound and finally into the grasp of the ULL. If not, it could certainly end up a far greater concern for the islands in the northern Caribbean, and ultimately perhaps the CONUS. (All speculation at this point, of course - we don't even have a TD to concern ourselves with there, yet).
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danielw
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| (Moderator) |
| Sun Sep 02 2007 05:32 AM |
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Re: Tropical Storm Felix forms in Southeastern Caribbean
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URNT12 KNHC 020557
VORTEX DATA MESSAGE AL062007
A. 02/05:40:40Z
B. 12 deg 40 min N
067 deg 40 min W
C. 700 mb 2975 m
D. 71 kt
E. 134 deg 007 nm
F. 236 deg 055 kt
G. 142 deg 012 nm
H. 986 mb
I. 6 C/ 3053 m
J. 13 C/ 3045 m
K. 9 C/ NA
L. OPEN NNE
M. C30
N. 12345/ 7
O. 0.02 / 2 nm
P. AF306 0606A FELIX OB 09
MAX FL WIND 93 KT N QUAD 05:09:00 Z
| CoconutCandy |
| (User) |
| Sun Sep 02 2007 06:37 AM |
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'Visualizing' a Ridge of High Pressure
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(Mods: Please feel free to move this post and it's question to the 'Hurricane Ask/Tell' Forum.)
>> Can someone please tell me where I can see a visual of a ridge, and explain to me what to look for?
(Reply to 'Texas Cane Tracker' from Post 77721. Apologies to the Mets. Any Mets feel free to extrapolate.)
Well, that's just it. You can't really 'see' a ridge. Since a ridge is high pressure, with sinking air and fair weather (as opposed to a trough of low pressure, with its' rising air and easily-visible stormy weather), there really isn't much to see, as air is normally transparent.
But what you *can* see is the effects of the ridge on the surrounding stratocumulus cloud fields over huge areas of open ocean.
You see, a ridge is an elongated area of high pressure, often extending for hundreds or even thousands of miles, usually east/west, and is sometimes anchored to a high pressure cell at one or both ends, but not always.
And since air flows *outward* from high pressure (inward towards low pressure) winds below (south of) the ridge "axis" blow generally from the E or ENE or NE, and, on the north side of the ridge axis, they blow from the W or WSW or SW.
It is the ridge, which is a semi-permanent feature in the summer months, that provides us the trade winds over the open oceans. Life without the tradewinds (they occasionally die down for various reasons) can be miserable, as they truly are natures' air-conditioning.
So, if you view a large area of ocean on a satellite map (visible daytime loop is better) which is clear and free of storms, you can see huge areas where the cumulus clouds are flowing along from the E or NE. But north of that area, you may see the clouds blowing in the opposite direction, from the W or SW. The broad, elongated, sometimes cloud free area which separates the two, is the ridge axis itself, which is sinking, dry air thus doesn't really provide anything to 'see'.
But, just because you can't see it, (except indirectly, by it's 'reflection' on the motions of the cloud fields over huge areas of ocean) the ridge is incredibly important because, as mentioned, it provides the trade winds, *AND* it 'steers' storms and hurricanes located below the ridge axis west or west-northwest.
Whenever you see a storm or hurricane moving west or west-northwest, as Hurricane Felix is currently doing, it is the effect of the all-important ridge gently 'pushing' it along and preventing it from moving very much northward.
When the ridge 'runs out' in it's horizontal extent, breaks down, or is eroded away, there forms, instead, a 'weakness' which the storms/hurricanes will tend to move towards. That's when the storms will turn NW or N or even NE, because the ridge is no longer there and no longer 'pushing' them westward.
Here's a good article from Wikipedia that should help you understand and 'visualize' the Subtropical ridge.
http://en.wikipedia.org/wiki/Subtropical_ridge
There's even a nice picture of the East/Central Pacific and the Hawaiian Islands in the article, showing the importance of the subtropical ridge in providing Hawaii with our nearly constant breezy cooling tradewinds.
| dem05 |
| (User) |
| Sun Sep 02 2007 09:46 AM |
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Re: Ferocious Felix Swells to Cat 2 Hurricane
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Well, the eye of Hurricane Felix is now becomming very identifyable on the satellite this morning...as can be seen on the JSL and Rainbow Floater loops.
JSL: http://www.ssd.noaa.gov/goes/flt/t1/loop-jsl.html
Rainbow: http://www.ssd.noaa.gov/goes/flt/t1/loop-rb.html
The radar loops from the French Antillies, which Mike C and company have posted under the main post on this thread paint an excellent radar representation of Felix as well this morning.
I've been pulling for the ABC islands in hopes that they will not see Hurricane Forcewinds down there today. It is definately not another day in paradise down there, but from the looks of it, Aruba and the Dutch Antillies may stay just far enough south of Felix to escape sustained winds of hurricane force...although hurricane force wind gusts are a slight, realistic possibility in one or two squalls down there.
Down range, the Nogaps has closed the gap on the rest of the model guidance, so the models may be approaching an agreement on a more specific path/direction of movement in the western Carribean. Unfortunately, this storm looks likeit is going to be another Hurricane for the history books. Otherwise, there is a low developing off the Georgia Coast this morning. Something to keep an eye on for potential slow development, as the more reliable models do carry some vorticity in the area off the SE US for the next few days. In the mean time, the models do not show this area of low pressure off of Georgia as a system that will have any significant affect on the ridging that is steering Felix on a w-wnw path.