Intensifying Hermine closes in on the Texas/Mexico coast

By: Dr. Jeff Masters , 9:47 PM GMT on September 06, 2010

Share this Blog
1
+

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

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 1336 - 1286

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 | 34Blog Index

1336. xcool
tornadodude .anytime.
Member Since: Posts: Comments:
Quoting Jedkins01:



I agree actually, I don't think Hermine actually grew stronger over land, it just appears that way, which was pretty exciting to me. Also, I believe the NHC is right, just based on my experience chasing a few tropical cyclones, and knowledge about weather, convection that strong could still support hurricane force gusts in Brownsiville, and I bet many people didn't expect it, even though the NHC had it in the forecast. Just because people were busy having fun on labor day, not checking the weather, and Hermine certainly didn't appear like it would be threatening this AM


Very true and I share your same concerns. As You, MLC, and others put it so well-it's about peoples safety first and foremost. It appears that some aren't aware just how much damage can occur from a strong TS (especially one that was in an intensification phase when it came ashore).

Based on the Brownsville obs, there is little doubt-in my mind anyway-that there will be quite a few trees down in the area. That alone can cause substantial damage and depending on who or what it might fall upon-even loss of life.

Before I call it a night myself, please let me say that I too believe that there may very well have been HF wind gusts in the Brownsville area. Even the 59 mph wind gust measured by "c150" with a hand held anemometer (I assume) supports that premise in that official wind gusts are representative of the max wind at a height of 10 m (33 feet) and they might not have actually measured the highest wind in the area and at the time of peak winds.

Most important of all, I just simply want to wish you, MLC, c150, and everyone else a safe and great rest of the night!:)
Member Since: Posts: Comments:
so sorry. :)

I said it was not my intention to argue with anyone, and once again I let myself be drawn in... although debate was not my intention.

Am taking my hands off the keyboard.... NOW!
Member Since: Posts: Comments:
Quoting JLPR2:
Well to change the mood a little which I see is a little tense, lets see the amazing thunderstorm complex Gaston has developed (sarcasm) LOL!



looks like an Annular with a pinhole eye that is creating its own favorable environment!
Member Since: Posts: Comments:
Quoting JLPR2:
Well to change the mood a little which I see is a little tense, lets see the amazing thunderstorm complex Gaston has developed (sarcasm) LOL!



XD
Member Since: Posts: Comments:
Quoting xcool:
matt.Brownsville


thanks Scott
Member Since: Posts: Comments:
Quoting 789:
oz reporting are you watching he is in it


yeah definitely am, just talked to him a little bit ago, he is getting into some wind and very heavy rain
Member Since: Posts: Comments:
1329. xcool
matt.Brownsville
Member Since: Posts: Comments:
SunnyDaysFl

I live on the tx coast and Texas Windstorm Insurance and Home Owners Policies are seperate policies unless you purchase windstorm insurance from an independent insurance company. Two seperate policies, 2 different deductibles
Member Since: Posts: Comments:
Quoting Jedkins01:


Well whether you believe in God, some scientific force, Aliens, Mother Earth, whatever, there is far too much order in this Universe for it to come by chance. To think it came by chance is quite mad don't you think? :)

Either way, we have free will to choose believe whatever we want...


inb4 religious debate
Member Since: Posts: Comments:
Quoting traumaboyy:


Same here....looks like if we take another big one if Florida....Probably just have to do without insurance if they price it much higher....but if you have a mortgage....well...you are stuck paying whatever they say to pay right!!


Yes. We still have a mortgage, so my biggest hurricane preparations this year has been to try to save as much money as possible to offset that deductible when and if we get a storm.
Member Since: Posts: Comments:
Quoting Bordonaro:

Probably near Brownsville, TX..


yeah most likely, have you seen what OZ is driving through? pretty crazy right now!

link
Member Since: Posts: Comments:
Quoting moonlightcowboy:



Was there a HW anywhere?
As far as I know, no. There was a hurricane watch in Texas, but no warning. I believe.
Member Since: Posts: Comments:
Interesting bit of info Cosmic---guess I should check my policy ---not that I have any options. lol
Member Since: Posts: Comments:
1322. 789
Quoting tornadodude:


I know, right?

yeah, how come crap like this never gets removed for violating standards?
oz reporting are you watching he is in it
Member Since: Posts: Comments:
Quoting tornadodude:


where?

Probably near Brownsville, TX..
Member Since: Posts: Comments:
1320. JLPR2
Well to change the mood a little which I see is a little tense, lets see the amazing thunderstorm complex Gaston has developed (sarcasm) LOL!

Member Since: September 4, 2007 Posts: 7 Comments: 8514
Quoting fatlady99:


as long as you are comfortable.


(ix-nay on the edkins01-jay)
Member Since: Posts: Comments:
Quoting xcool:
Wind Speed: SE43.7MPH G TO58.7(38MPH G TO51KT)
Barometer: 29.54 in


where?
Member Since: Posts: Comments:
1317. GBguy88
Brownsville is still seeing the occasional gust over 60mph.
Member Since: Posts: Comments:
1316. xcool
Wind Speed: SE43.7MPH G TO58.7(38MPH G TO51KT)
Barometer: 29.54 in
Member Since: Posts: Comments:
Quoting CosmicEvents:
Obviously...a very financially important difference. Good point. Check your policy. Some have the hurricane deductible kicking in if a hurricane warning gets posted anywhere in the state. So even if you're hit with a tropical storm, the "warning" gets you.



Was there a HW anywhere?
Member Since: Posts: Comments:
Quoting Jedkins01:


as long as you are comfortable.
Member Since: Posts: Comments:
OceanMoan---my sympathy. I do know of people who are essentially just insuring for catastrophic damage to keep premiums down.(ie $25,000 deductibles)
Member Since: Posts: Comments:
Quoting OceanMoan:


I am in South Carolina. I have one deductible for any tropical cyclone, and it is twice what your hurricane deductible is. I was furious when they changed it a few years ago.


Same here....looks like if we take another big one if Florida....Probably just have to do without insurance if they price it much higher....but if you have a mortgage....well...you are stuck paying whatever they say to pay right!!
Member Since: Posts: Comments:
Quoting SunnyDaysFla:
Just curious---are the homeowners insurance deductibles the same in Texas as Florida? Here mine is $1000 for tropical storm damage but $4700 for hurricane. Big difference for 5mph.
Obviously...a very financially important difference. Good point. Check your policy. Some have the hurricane deductible kicking in if a hurricane warning gets posted anywhere in the state. So even if you're hit with a tropical storm, the "warning" gets you.
Member Since: Posts: Comments:
1310. GBguy88
Quoting Jedkins01:



Yeah that is what I am saying, the NHC does review these systems, and may find something different then first thought, however, itds probably due to the fact that Hermine was in an intensification phase up until landfall, also, environmental conditions overland have probably been favorable enough to help hold it in tact longer.

I just know most of the time, a 65 mph storm at landfall usually doesn't hold this strong for this long, intriguing indeed that's fore sure.


I don't think that the winds were sustained at hurricane force, but certainly reached it in a few gusts. I don't know if that warrants upgrading it to a hurricane in a post analysis. Either way though, it's already clear that Hermine made a hefty mess of things in Brownsville. Good thing she didn't have another 12 hours over water, or this would have easily been another Humberto situation.
Member Since: Posts: Comments:
Quoting fatlady99:

must you? :)


Well whether you believe in God, some scientific force, Aliens, Mother Earth, whatever, there is far too much order in this Universe for it to come by chance. To think it came by chance is quite mad don't you think? :)

Either way, we have free will to choose believe whatever we want...
Member Since: Posts: Comments:
Cyclone Oz is playing Ozzy... ahaha. This guy just cracks me up.

http://thextremeweather.com/xtreme-weather-cam.html
Member Since: Posts: Comments:
Quoting ConchHondros:
Rare its like your speaking Greek with marbles in your mouth, which I have actually done...involed Ouzo and an English nurse in Rhodes...anyway, civil?...here? Dude, when Oz gets his chatroom going, his dopey minions will leave and we wil have some normal behavior on the blog.


LOL! Believe it or not, it was an innocuous joking post like yours that illicited that rediculous string of posts.
Member Since: Posts: Comments:
Quoting ConchHondros:
Rare its like your speaking Greek with marbles in your mouth, which I have actually done...involed Ouzo and an English nurse in Rhodes...anyway, civil?...here? Dude, when Oz gets his chatroom going, his dopey minions will leave and we wil have some normal behavior on the blog.


I know, right?

yeah, how come crap like this never gets removed for violating standards?
Member Since: Posts: Comments:
Quoting SunnyDaysFla:
Just curious---are the homeowners insurance deductibles the same in Texas as Florida? Here mine is $1000 for tropical storm damage but $4700 for hurricane. Big difference for 5mph.


I am in South Carolina. I have one deductible for any tropical cyclone, and it is twice what your hurricane deductible is. I was furious when they changed it a few years ago.
Member Since: Posts: Comments:
Quoting PrivateIdaho:


You've got to be kidding me! Just when you think Insurance companies can't sink lower.


Unbelievable! Then it would not surprise me to see Hermine upgraded to Cat 1 status in post-storm analysis, considering the insurance lobby. Although the official position at landfall was TS. Good grief - crazy!
Member Since: Posts: Comments:
Quoting moonlightcowboy:



Absolutely. Afterall, it's about safety foremost - not classification. Hermine developed quickly and came ashore during intensification. It will be interesting to see if there is any post analysis that might discern Hermine accomplished Cat 1 status, but I've my doubts. Landmass does usually weaken a system quickly after coming ashore. Status or not, Hermine is still a dangerous system with damaging winds and flooding potential. Hopefully, any in its path received due warning and made last-minute safety precautions.



Yeah that is what I am saying, the NHC does review these systems, and may find something different then first thought, however, itds probably due to the fact that Hermine was in an intensification phase up until landfall, also, environmental conditions overland have probably been favorable enough to help hold it in tact longer.

I just know most of the time, a 65 mph storm at landfall usually doesn't hold this strong for this long, intriguing indeed that's fore sure.
Member Since: Posts: Comments:
Rare its like your speaking Greek with marbles in your mouth, which I have actually done...involed Ouzo and an English nurse in Rhodes...anyway, civil?...here? Dude, when Oz gets his chatroom going, his dopey minions will leave and we wil have some normal behavior on the blog.
Member Since: Posts: Comments:
No joke---pretty awful for people without cash reserves. You can get it lower by paying a higher premium,but our premiums are already awful.
Member Since: Posts: Comments:
alright im calling it a nite got to go back to work tomorrow. You guys play nice, Out
Member Since: Posts: Comments:
Quoting Jedkins01:

must you? :)
Member Since: Posts: Comments:
Quoting fatlady99:


Bless you, Jedkins. Not everyone sees it your way. Nor should they have to. 'Either Science or God'is not a dictate that I care to be limited to. The Bard said it best...

"O day and night, but this is wondrous strange!...

And therefore as a stranger give it welcome.
There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy."



Well I put science and God because if you don't believe in God, you must agree at least that science around you governs things.
Member Since: Posts: Comments:
Quoting SunnyDaysFla:
Just curious---are the homeowners insurance deductibles the same in Texas as Florida? Here mine is $1000 for tropical storm damage but $4700 for hurricane. Big difference for 5mph.


You've got to be kidding me! Just when you think Insurance companies can't sink lower.
Member Since: Posts: Comments:
Really this is getting old. Stop the BS and lets look at what's happening. You guys have spent the last 4 pages arguing about 8MPH +/- A strong TS or cat 1 not a big difference. They have damage and they have a stronger side coming. The guy in Brownsville gave you his data from the windguage he was holding in his hand. Good folks on here most of the time lets keep this civil so we can continue to enjoy each others insight.
Member Since: Posts: Comments:
Quoting KanKunKid:


Another problem with assessing wind damage is the wind speed at the location the damage took place. Most of them are estimated by using certified devices miles away. So unless you have an anemometer and are watching it or recording its data, you won't know exactly how fast the wind was going. That is one of the reasons for the enhanced Fujita system of measuring a tornadoes wind speed AFTER it has done its damage.


Very true! Thanks. I was watching the info on WU for my area while we still had power, but that didn't last long! Not during any of them...
Member Since: Posts: Comments:
Quoting ncforecaster:
I haven't followed much of the conversation. That being said, please allow me to state (for the record) that winds sustained at 50 mph+ and wind gusts up to and/ or exceeding HF can do quite a bit of damage-especially from falling tress.



Absolutely. Afterall, it's about safety foremost - not classification. Hermine developed quickly and came ashore during intensification. It will be interesting to see if there is any post analysis that might discern Hermine accomplished Cat 1 status, but I've my doubts. Landmass does usually weaken a system quickly after coming ashore. Status or not, Hermine is still a dangerous system with damaging winds and flooding potential. Hopefully, any in its path received due warning and made last-minute safety precautions.
Member Since: Posts: Comments:
sorry double post
Member Since: Posts: Comments:
Just curious---are the homeowners insurance deductibles the same in Texas as Florida? Here mine is $1000 for tropical storm damage but $4700 for hurricane. Big difference for 5mph.
Member Since: Posts: Comments:
Quoting houston144:
TORMENTOSO83,

check out this, it is a bit to grip but it will put you in the "drivers seat", there an extra surprises under the "brown-eyes" button. and there is a Desktop gauge also you can d/l with it. the software works real nice if your use to GE then it won't be to hard.

Link

THANK YOU MY FRIEND!
Member Since: Posts: Comments:
Quoting Jedkins01:


Bless you, Jedkins. Not everyone sees it your way. Nor should they have to. 'Either Science or God'is not a dictate that I care to be limited to. The Bard said it best...

"O day and night, but this is wondrous strange!...

And therefore as a stranger give it welcome.
There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy."
Member Since: Posts: Comments:
Quoting KanKunKid:




Oh no you didn't!
Member Since: Posts: Comments:
Quoting ncforecaster:


Hi Jedkins...I appreciate many of your points and respect your opinion/knowledge. That being said, TS Hermine most certainly did not continue to intensify after it crossed the shoreline. If you review the radar loops, you will see that the eye-like feature began to fill in immediately after it came ashore and the radial velocities from the WSR 88D scan had decreased.

It is not unusual for the convection around the eyewall to develop colder cloud tops after landfall occurred-but that doesn't translate into a deepening storm.

It is also important to note the disparity between the MSW and the peak 3 second gusts over land as well. In the case of the Brownsville, TX observation being discussed...it was a 44 mph sustained wind with a gust to 69 mph. That is basically a 6 to 1 ratio between the two when most are 3 to 1 over marine exposure. Consequently, it is a mistake to make assumptions of the MSW 1 minute wind speed based upon a 3 second gust measurement.

In short, there is no data available to support Hermine having come ashore as anything greater than a 65 mph strong TS. That being said, it is still a very significant storm that should be taken seriously by those who are being affected by it. It is most certainly conceivable that some areas have experienced HF wind gusts and that can and does cause damage.



I agree actually, I don't think Hermine actually grew stronger over land, it just appears that way, which was pretty exciting to me. Also, I believe the NHC is right, just based on my experience chasing a few tropical cyclones, and knowledge about weather, convection that strong could still support hurricane force gusts in Brownsiville, and I bet many people didn't expect it, even though the NHC had it in the forecast. Just because people were busy having fun on labor day, not checking the weather, and Hermine certainly didn't appear like it would be threatening this AM
Member Since: Posts: Comments:
1286. leo305
here comes pt2 brownsville..

the esat side is going to slam in..
Member Since: April 17, 2010 Posts: 0 Comments: 1753

Viewing: 1336 - 1286

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 | 34Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Partly Cloudy
74 °F
Partly Cloudy