Western Caribbean disturbance 98L a threat to develop; Otto weakening
An area of disturbed weather (98L) is in the Western Caribbean, a few hundred miles east of the coast of Nicaragua. The disturbance has a modest and slowly increasing amount of intense thunderstorms, and is showing some spin. The disturbance is drifting northwest at less than 5 mph, and is under a moderate 15 knots of wind shear. Dry air in the Western Caribbean has been interfering with development, but 98L is now generating enough thunderstorms that the environment in the Western Caribbean is moistening, which will support further development. Pressures at Colombia's San Andres Island near the center of 98L are not falling, and satellite imagery show disturbed weather only over a very modest portion of the Caribbean, so any development today will be slow to occur.
Figure 1. Morning satellite image of 98L.
Forecast for 98L
98L is likely to bring heavy rains to northeastern Honduras and Nicaragua on Sunday, and possibly the Cayman Islands and Jamaica as well. The latest SHIPS model forecast calls for wind shear to stay in the moderate range, 10 - 20 knots, through Tuesday. This should allow 98L to reach tropical depression status early next week, though NHC is only calling for a 20% chance of 98L becoming a tropical depression by Monday morning. The GFDL and HWRF models are the most aggressive developing 98L. These models predict 98L will intensify into Tropical Storm Paula by Monday, move northwest and then north, and pass through the Cayman Islands on Monday night and Tuesday morning as a tropical storm. Paula would then hit western or central Cuba as a hurricane on Tuesday or Wednesday, brush the Florida Keys, then accelerate northeastward through the western Bahamas on Wednesday or Thursday. This is probably too aggressive of a forecast, given 98L's current small size and lack of organization. The UKMET model also develops 98L, but keeps the storm in the Western Caribbean over the next seven days. The NOGAPS model keeps 98L weak and predicts a more west-northwesterly motion into Mexico's Yucatan Peninsula on Wednesday. The GFS and ECMWF models do not develop 98L. One argument against the development of 98L would be that the phase of the Madden-Julian Oscillation is currently promoting sinking, stable air over the Western Caribbean, which tends to make the atmosphere dryer and more stable. However, I think that 98L will spend enough time in the Western Caribbean to overcome the relatively stable, dry air, and become a tropical depression or tropical storm by Tuesday. The likelihood of the storm hitting Cuba versus moving more to the west-northwest and hitting Mexico's Yucatan Peninsula is difficult to call at this point.
Otto weakening, pulling away from the the islands
The deluge has finally ended for Puerto Rico, the Virgin Islands, and the northern Lesser Antilles Islands from Hurricane Otto. This is welcome news in St. Thomas in the U.S. Virgin Islands, where Otto and its precursor storminess dumped 15.25" of rain over the past eight days. On average, St.Thomas expects to receive just 1.44" of rain during the first eight days of October. Satellite imagery shows that Otto is beginning to suffer the ill-effects of high wind shear of 20 - 30 knots. The cloud pattern has become distorted and non-symmetric, with the clouds on the southwest side of the storm being eaten away by the strong upper-level winds from the southwest creating the shear. Otto will continue to deteriorate due to increasing wind shear until the storm transitions into an extratropical storm on Monday.
Figure 2. Satellite image of Otto taken by NASA's MODIS instrument on their Terra satellite at 11:05 am EDT October 8, 2010. Image credit: NASA.
A challenge to the validity of the world extreme heat record of 136.4°F (58°C) at Al Aziza, Libya
One of the "sacred cows" of world weather extremes has been the widely reported "hottest temperature ever recorded on earth", a reading of 58°C (136.4°F) reported from Al Azizia, Libya on Sept. 13, 1922. In a remarkable piece of research, our featured Weather Extremes blogger Christopher C. Burt concludes: the temperature observations at Al Azizia prior to 1927 (when the site and instruments were changed) are obviously invalid. The shelter housing the thermometer was most likely over exposed and measuring heat radiating of off the black-tarred concrete of the terrace on which it was placed.
Has Mr. Burt slain one of meteorology's most sacred cows? You be the judge. Check out the full story at his blog.
I'll have an update Sunday by 2pm EDT.
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 — Blog Index
Exactly, sometimes if surface moisture is deep enough, you can sustain deep convection as long as convergence and thermodynamic profiles are favorable. But you still have to measure the actual available moisture to have any meteorological credibility. For example, if an air mass has dry in upper levels, but there is sufficient convergence and the right thermodynamics in place, combined with high enough PW's, you get convection.
This happens in Florida a lot during the summer months, as well as much of the tropics. However, you still have to measure the PW or overall moisture content. Lets say you have a temp at 90 degrees, with a dew point of 74. Yes it feels very humid, but if the PW is 1.30 inches, most of that moisture is ground level. Indicating an overall way too dry air mass for deep convection, also this usually indicates a subsidence inversion with even less likely chances for convection.
However, lets say you have a different air mass with a temperature at 90 once again, and a dew point of 74 feeling just as humid, accept this time the PW is 2.10 inches. Even though the air aloft is dry, such a high PW is easily enough for deep convection and torrential rain, as long as lapse rates are steep enough and convergence is decent.
We'll see, bf. Fair lapse rates will make the most of the meager moisture-but still a tough job, imo. The cut-off low may be a little too far to the north to affect 98l-but it should pull a narrow plume of moisture over OK.
Ok, I am now off to shoot something uh, wearing my pajamas...
Night, all.
Thanks for your thoughts, bl.
Any convection, deep or shallow, even with limited moisture, will be welcome here. I'm having trouble delineating Pacific trough from the cut-off low.
I do hope OK gets some much-needed rain.
(graphic added)
'Nite again.
Ps. Great finish for LSU!
it looks like 98L is sending moisture westbound and that is what is running into the system from 120w to 150w. so in a way she is venting moisture way out in the pacific only to have it sent right back into the northern GOM..,...so, in a way, isn't 98L already in the GOM? lol
http://www.goes.noaa.gov/HURRLOOPS/hpwv.html
98L looks like it is starting to create a more conductive environment above the northwest quad. if shear decreases to the north and 98L can spend enough time south to allow venting of moisture to her northwest she could build a nice path to follow north. That could help her intensify significantly once she does make her move northbound from her present stationary position.
Temperatures are quite a bit warmer here along the Northern GOM tonight as compared to last night. Now approaching 48 hours since the trough began to give way and things have changed dramatically. 2 nights ago I got so cold I had to wear a flannel, and I am originally from Colorado....lol....Now it is 12:30 and I have the backdoor open just to cool the house down from late afternoon. It's not blazing hot here (i haven't run the a/c) but still a big change from just 2 nights ago.
Lower level steering winds (700-850) show the weak high pressure over the gulf. I think this may be part of what is keeping 98L where she is....
http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8dlm1.html
however, if she starts to gain strength and the millibars drop watch what happens in the mid levels
(500-850)
http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8dlm2.html
(400-850)
http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/
(300-850)
http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8dlm4.html
the trend with the high pressure to the west over mexico continues at 250-850.
it would seem as if the likelihood of 98L heading directly north once she gains ts strength is high. the high pressure to the east is gonna direct her north and the high to the west over mexico is going to deflect her away from a mexican GOM landfall. At higher levels it even appears that she has a very narrow alleyway between the 2 high pressures heading directly north into western cuba.
once she gains strong ts strength she will probably begin her move north. if and when that happens is uncertain, but the current steering winds certainly suggest it.
dry air at night equals massive cooling of the gulf
oh sorry didnt mean to insinuate something wrong. i was just responding to the guy that said it is getting more muggy here along the northern GOM. that really had nothing to do with 98L. sorry about the confusion
lmao...been awhile since i have heard some good jello, klaus, and east bay ray lmao
09Oct 06amGMT - - 28.5n59.7w - - 75knots - - 977mb -- NHC-ATCF
09Oct 09amGMT - - 29.2n58.5w - - 85mph - . - 977mb -- NHC.Adv. #13
09Oct 12pmGMT - - 30.1n57.1w - - 65knots - - 984mb -- NHC-ATCF
09Oct 03pmGMT - - 30.7n55.7w - - 75mph - . - 984mb -- NHC.Adv.#14
09Oct 06pmGMT - - 31.7n54.0w - - 65knots - - 984mb -- NHC-ATCF
09Oct 09pmGMT - - 32.4n52.6w - - 75mph - . - 984mb -- NHC.Adv.#15
TropicalStormOtto
10Oct 12amGMT - - 33.1n50.4w - - 60knots - - 988mb -- NHC-ATCF
10Oct 03amGMT - - 33.9n48.7w - - 70mph - . - 988mb -- NHC.Adv.#16
10Oct 06amGMT - - 34.3n46.8w - - 55knots - - 987mb -- NHC-ATCF
55knots=~63.3mph=~101.9km/h __ 65mph=~104.6km/h __ 60knots=~69mph=~111.1km/h
70mph=~112.7km/h __ 65knots=~74.8mph=~120.4km/h __ 75mph=~120.7k/h
70knots=~80.6mph=~129.6km/h __ 80mph=~128.7km/h __ 75knots=~86.3mph=138.9km/h
85mph=136.8km/h
MaximumSustainedWind speeds are rounded to the nearest 5mph or to the nearest 5knots
Copy&paste 28.5n59.7w, 29.2n58.5w, 30.1n57.1w, 30.7n55.7w, 31.7n54.0w-32.4n52.6w, 32.4n52.6w-33.1n50.4w, 33.1n50.4w-33.9n48.7w, 33.9n48.7w-34.3n46.8w, 34.3n46.8w-bda, 34.3n46.8w-hor, flw into the GreatCircleMapper for a look at the last 12hours
TS.Otto is now closer to westernmost Azores (FLW) than to Bermuda (BDA)
144 hr. ECMWF....
I saw the panther's play and a hockey game almost broke out... But then it went back to the Saturday night fights...
How are the surfing conditions by you today? I noticed on Friday a lot of surfboards on top of cars going to the beach.
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SUN OCT 10 2010
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM OTTO...LOCATED ABOUT 1015 MILES WEST OF THE AZORES.
SHOWER AND THUNDERSTORM ACTIVITY CONTINUES IN ASSOCIATION WITH AN
AREA OF LOW PRESSURE LOCATED ABOUT 150 MILES EAST OF THE COAST OF
NICARAGUA. CONDITIONS APPEAR CONDUCIVE FOR A TROPICAL DEPRESSION TO
FORM DURING THE NEXT DAY OR TWO...AND THERE IS A HIGH CHANCE...60
PERCENT...OF TROPICAL CYCLONE FORMATION IN THE NEXT 48 HOURS AS THE
SYSTEM MOVES WEST-NORTHWESTWARD OR NORTHWESTWARD AT 5 TO 10 MPH.
REGARDLESS OF DEVELOPMENT...HEAVY RAINFALL IS POSSIBLE DURING THE
NEXT COUPLE OF DAYS OVER PORTIONS OF NICARAGUA AND HONDURAS.
ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
$$
FORECASTER BRENNAN
photo: gulfster
this made me groan..... haven't seen waves like this on the Gomex since Dolly - what a drought here for surfers....
photo: Aurasurf
We don't get much in South Florida, so everyone I know that surfs goes to Central Florida on the east coast to surf.
Nice Photos. Thanks for sharing.
Areas in the parish of Westmoreland, like Negril, Savanalamar, and the parish St. Elizebeth appear to be getting light to moderate rainfall.
Met Service in Jamaica Radar
It's been a terrible surf season on the Gulf Coast of Florida. Usually we get a tropical storm or two to bring us some waves. This year nothing.
I usually drive to the Cocoa area to do most of my surfing. We usually rent a place for at least a week during the summer to get some waves. We just watch the surf report and when we see a good surf window (several days of good surf) we rent a place on or near the beach.
That's cause for celebration, I think. :-)
Click for larger image:
If that means rain for Louisiana, I'll be jumping for joy. Put the dog out last night and my eyes stung from smoke. No idea where it was coming from, but with the statewide burn ban, it made me very nervous.
AL, 98, 2010101012, , BEST, 0, 130N, 812W, 25, 1007, LO, 34, NEQ, 0, 0, 0, 0, 1010, 200, 35, 0, 0, L, 0, , 0, 0, INVEST, M,
do you what to know why Neapolitan because the ATCF has NFI
yes very reasonable but its looking like its going to stay so close to land all its life it wont be much more than a ts
Models for 98L...
Latest HWRF on 98L...Link
And he has been correct all season.
Viewing: 751 - 801
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 — Blog Index