Intensifying Hermine closes in on the Texas/Mexico coast
Steadily intensifying Tropical Storm Hermine is closing in on the coast near the Texas/Mexico border, and should move ashore late tonight. Hermine became a tropical depression at 11pm last night, and could become a minimal hurricane by 11 pm tonight. Hermine's rate of intensification from nothing to a strong tropical storm is one of the fastest on record. It turns out that the extreme southwestern Gulf of Mexico's Bay of Campeche, where Hermine formed, is prone to these sort of rapidly intensifying tropical storms. The curvature and topography of the land help induce a counter-clockwise spin to the air over the region, which helps get tropical storms spinning up unusually quickly. Helping the spin-up process are the very warm 30°C waters, low 5 - 10 knots of wind shear, and moist atmosphere. Hermine promises to be a very wet storm, and latest long range radar out of Brownsville, Texas shows a large area of heavy rain has been drenching southern Texas and northern Mexico all afternoon, with radar estimated rainfall amounts exceeding two inches in a few areas along the coast. Radar loops show that an eyewall is attempting to form, but a region of dry air from over land spiraled into Hermine's core between 4 - 5pm EDT, disrupting eyewall formation. However, it now appears that Hermine has closed off its eye from this dry air, which should aid in intensification. Satellite imagery shows Hermine has vigorous thunderstorms with very cold tops, and improving low-level spiral banding.
Forecast for Hermine
Hermine doesn't have much time over water before it comes ashore, which is a good thing. The storm is steadily organizing, and has a shot at reaching hurricane strength before the center moves ashore late tonight, near midnight. Heavy rain will be the main threat from Hermine, though isolated tornadoes may also cause damage, particularly over South Texas. Hermine is expected to accelerate through Central Texas Tuesday and Wednesday, and the storm's rains will help alleviate moderate to severe drought conditions affecting Central Texas.
Figure 1. Late afternoon radar image of Tropical Storm Hermine. Note the band of dry air spiraling into the core of the storm from the north.
Gaston continues to suffer from dry air
An Air Force Hurricane Hunter aircraft spent the afternoon in Gaston's remains, and found a weak 1012 mb center of low pressure with only a limited region of westerly winds on the south side of the center of circulation. Top surface winds uncontaminated by heavy rain seen by their SFMR instrument were in the 30 - 35 mph range. The airplane found plenty of dry air in the storm's environment, and there are not enough heavy thunderstorms in ex-Gaston's circulation for it to qualify as a tropical depression. The remains of Gaston are now approaching the northern Lesser Antilles, and residents can expect a few heavy rain showers and wind gusts up to 40 mph beginning early this evening and continuing into the night. Latest radar out of Martinique doesn't show much in the way of heavy rain, and satellite imagery confirms that the thunderstorm activity associated with Gaston's remains is quite sparse. A large amount of dry air surrounds Gaston's remains on all sides, as seen on water vapor satellite loops.
Figure 2. Afternoon satellite image of the remains of Gaston, approaching the Lesser Antilles Islands.
Forecast for Gaston
There is little change to the forecast for Gaston's remains. Dry air will continue to be the major impediment to development, and the system is unlikely to become a tropical depression today. However, wind shear, which is currently a moderate 10 knots, is forecast by the latest SHIPS model run to fall very low, 0 - 5 knots, tonight through Wednesday. With almost no wind shear affecting it, Gaston will a better chance of keeping the moisture from its heavy thunderstorms near its core on Tuesday. This will insulate the storm from the dry air surrounding it. The atmosphere is also moister in the eastern Caribbean, further increasing the chances of development. I believe it is probable Gaston will become a tropical depression again on Tuesday. NHC is currently giving Gaston a 70% chance of developing into a tropical depression by Wednesday, which is a reasonable forecast.
Heavy rain showers and gusty winds from the storm will affect Puerto Rico Tuesday morning through Wednesday afternoon. This activity will spread to the Dominican Republic Tuesday afternoon through Thursday morning. Assuming dry air and an encounter with Hispaniola's high mountains do not destroy Gaston, heavy rain from the storm should move over Haiti, eastern Cuba, and Jamaica Wednesday night and Thursday morning. The models don't give much support for Gaston surviving past Wednesday. The ECMWF, GFS, NOGAPS, Canadian, and HWRF models all dissipate Gaston. However, two models--the GFDL and UKMET--predict that Gaston will survive the dry air and an encounter with Hispaniola, and pass far enough south of the island to find a favorable environment in the Central Caribbean for development on Wednesday. Wind shear will be low, water temperatures will be hot, and the atmosphere will be plenty moist. Gaston could intensify into a hurricane in the Western Caribbean by the end of the week, as predicted by the latest run of the GFDL model.
Elsewhere in the tropics
The models are fairly unanimous in predicting development late this week of a tropical wave expected to emerge from the coast of Africa on Tuesday or Wednesday. The next storm will be called Igor.
Next post
I'll have an update in the morning.
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 — Blog Index
or I a good Teapot w/ Earl GREY.....
never, ever Sugar in my Tea......even iced.
Coops - Been Up *giggle* --just did the Pooch walk first - she loves being first at the telephone poles & mail box posts LOL
So Gaston - Is he or isn't HE, gone, gone, gone - no fuel or or remnants left? and the next one is named ..Igor???? Wonder what Baby Name Book these guys were looking at????
Flash flooding in Aransas and Refugio Counties. We have another band moving over just at the time I leave for work--may have to call the boss and tell him I'll be a little late since my car sits low!
I would -- takes the pressure off, better not to have to fret about being late - and maybe he'll be kind let you stay home....
Stay out of the 'dips' - Lord knows it doesn't take much to flood in that area...
boss will probably be surfing if it's not like a washing machine out there.
*smile* Ohhh, I know his type -- he may wait for it to lay down today and be out tomorrow....tell him you'll meet him at the beach with a camera -- that might get you a day off and a trip to the beach... seriously though be careful -- car-float is not good, that's what Kayaks are for
Going to be a another wet day here,day 1 of 4 days of possible widespred rain/T-storms
Metoffice
FOR THE PERIOD TODAY UNTIL MIDNIGHT:
TRINIDAD,TOBAGO AND THE Southern Windwards
Fair except for some afternoon showers and
isolated afternoon thundershowers. Expect some
showers overnight.
Ummmm...what? I see a lot more yellows and browns and reds than I do shades of blue. It's dry in the A/B high, of course, but that aridity defines it.
I see we're back this morning to downcasting the season. We've seen the birth of five named storms in a 14-day span, we had a landfalling high-end tropical storm just nine hours ago, our ACE is well over half of normal, and there's a very vigorous wave rolling off of Africa this morning with more behind it. Throw in what's left of Gaston, which still has a chance...and only the most foolish would say nothing's going on in the tropics.
Good Morning...
Nah! You still have to climb, for 3 days....
7:00 AM CDT Tue Sep 7
Location: 27.7°N 98.2°W
Max sustained: 45 mph
Moving: NNW at 17 mph
Min pressure: 995 mb
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT TUE SEP 7 2010
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM HERMINE...LOCATED INLAND ABOUT 50 MILES WEST OF CORPUS CHRISTI
TEXAS.
CLOUDINESS AND SHOWERS OVER THE LEEWARD ISLANDS AND THE NORTHEASTERN
CARIBBEAN SEA ARE ASSOCIATED WITH THE REMNANTS OF GASTON. THIS
SYSTEM IS EXPECTED TO CONTINUE WESTWARD AT 15 TO 20 MPH WITH NO
SIGNIFICANT DEVELOPMENT DURING THE NEXT COUPLE OF DAYS.
THERE IS A LOW CHANCE...10 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE AGAIN DURING THE NEXT 48 HOURS.
A WEAK AREA OF LOW PRESSURE LOCATED ABOUT 350 MILES WEST OF THE
NORTHERNMOST CAPE VERDE ISLANDS IS PRODUCING DISORGANIZED CLOUDINESS
AND SHOWERS. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN
UNFAVORABLE FOR DEVELOPMENT DURING THE NEXT COUPLE OF DAYS AS THE
LOW MOVES WESTWARD NEAR 10 MPH. THERE IS A LOW CHANCE...10
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.
SHOWERS AND THUNDERSTORMS LOCATED BETWEEN THE CAPE VERDE ISLANDS AND
THE WEST COAST OF AFRICA ARE ASSOCIATED WITH A TROPICAL WAVE.
DEVELOPMENT...IF ANY...OF THIS SYSTEM IS EXPECTED TO BE SLOW TO
OCCUR AS IT MOVES WESTWARD AT 10 TO 15 MPH DURING THE NEXT COUPLE
OF DAYS. THERE IS A LOW CHANCE...10 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
$$
FORECASTER CANGIALOSI/PASCH
The models show nothing through November 30th...
Hi!
Going to be more 'hot' than 'wet' I think.
Rains should be here late tonight?
Hey man,morning
If you buy the gfs its going to be wet,yea starting this afternoon then more widespred overnight(accordingi to the met.office),definately alot of moisture coming in.
True and I remember a few asking...why are the models(GFS, ECMWF, CMC and NOGAPS), killing Gaston off?
True!
well, that don't seem right.....but, then considering we are days away from peak, there isn't much to talk about.
It was not meant to be taken seriously...
I think you meant wasn't? :)
Strange contradiction, that.
What a weird season this has been....
You forgot to add 2011. :)
Next on the list is Igor.
Yea there should be more AOI out there
I'm out ttyl
Way to GO!
It's always good to see a good balance of views on the blog.
LMAO...Stick a fork in him and a nuke bomb. Pretty much covers all the bases.
06Sep . 12pmGMT - - 22.4n95.3w - - 45mph - - - 995mb - - NHC.Adv.#2A
06Sep . 03pmGMT - - 23.4n95.8w - - 50mph - - - 998mb - - #3
06Sep . 06pmGMT - - 24.1n96.5w - - 60mph - - - 995mb - - #3A
06Sep . 09pmGMT - - 24.5n97.0w - - 60mph - - - 992mb - - #4
07Sep . 12amGMT - - 24.8n97.1w - - 65mph - - - 991mb - - #4A
1:30amGMT landfall on 25.3n97.4w @ 65mph & 991mb (not used on the plot chart)
07Sep . 03amGMT - - 25.5n97.5w - - 60mph - - - 991mb - - #5
07Sep . 06amGMT - - 26.1n97.7w - - 60mph - - - 991mb - - #5A
07Sep . 09amGMT - - 27.0n98.0w - - 50mph - - - 993mb - - #6
07Sep . 12pmGMT - - 27.7n98.2w - - 45mph - - - 995mb - - #6A
Copy and paste 22.4n95.3w, 23.4n95.8w, 24.1n96.5w, 24.5n97.0w, 24.8n97.1w-25.5n97.5w, 25.5n97.5w-26.1n97.7w, 26.1n97.7w-27.0n98.0w, 27.0n98.0w-27.7n98.2w, crp, mam, sat into the GreatCircleMapper for a look at the last 12hours.
Viewing: 1551 - 1601
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 — Blog Index