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Atlantic Tropical Weather Update 8/30/08

Hurricane Gustav has passed over the deep, very warm waters between Jamaica and Cuba. In doing so, he rapidly strengthened overnight from a Category 1 hurricane to a Category 3 storm this morning, making him the second major hurricane of the 2008 Atlantic season. Bertha was the other major hurricane, but remained well out to sea her entire lifetime. Gustav’s vitals as of 8:30A MDT:

Center located at 20.8N, 81.6W; maximum sustained winds of 120mph; moving NW @ 11mph; minimum pressure is down all the way to 955mb, which is 33mb less than the reading yesterday. That is quite the rapid intensification. In fact, since the pressure has continued to drop steadily this morning, expect Gustav to strengthen even further today before eye-wall replacement cycles, a slightly cooler pool of water and the island of Cuba work to weaken him somewhat.

Gustav should still make landfall over Cuba later tonight as a Category 3 storm. A solid eye-wall did develop overnight. Gustav has an impressive outflowing cloud shield. Hurricane force winds were found on the northeast quadrant on an earlier hurricane hunter flight. As they get going again today, a clearer picture of where they are found will be available. Tropical Storm force winds extend all the way to Cuba, a decent distance from the storm’s center. Western Cuba is under a Hurricane Warning today.

Model solutions have come to closer agreement as of today. There is a much narrower band encompassing the solutions through the Gulf of Mexico, which Gustav will enter 12-24 hours from now. While Gustav crosses the central Gulf, he is still forecasted to overrun the Gulf Loop Current’s warmest stretch. The model intensity forecast has him strengthening to a Category 4 hurricane during this time, but I wouldn’t be surprised to see him go all the way to a Category 5. After that, there is very good agreement about the likely landfall location: the middle of the Louisiana coast. He should make landfall between Morgan City and Lake Charles. The timing is coming into better focus. The suite of models are also in pretty good agreement that the landfall could occur Monday night.

Post-landfall may not offer a better story than during landfall. Due to the strength and orientation of the ridge that will remain over the eastern U.S., Gustav could stall over Louisiana. We’ve already dealt with one slow moving storm: Fay dropped incredible amounts of rainfall over Florida just a week or so ago. Gustav shouldn’t dump quite that much rain, but the longer he lingers, the more flooding far inland will be a concern. New Orleans residents are smartly already evacuating. I’m sure other Gulf coast residents will follow similar measures throughout the next two days.

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Atlantic Tropical Weather Update 8/29/08

I would like to start by acknowledging the events of 3 years ago.  Hurricane Katrina by this point in the day, currently 9A MDT, had made landfall and was in the midst of catastrophically damaging one of America’s major cities.  That city still hasn’t recovered from the storm.  Neither have the areas along the Gulf coast that were similarly affected.  The Army Corps of Engineers has since worked to repair the levee system and even announced that they were rebuilt to withstand another Category 3 storm.  Let’s hope the residents of New Orleans don’t have to find out whether that’s true or not.  My opinion is that the levees aren’t strong enough.  It will require elected officials that actually care about their fellow citizens to take serious action in the Gulf coast region.  It will require yet more time and money to prepare the region for the next major storm.

We’re edging closer to the time when Gustav could directly impact the U.S.  He slowly made his way across Jamaica overnight and now has nothing but warm oceans and marginally unfavorable wind shear to contend with.  Let’s begin by looking at his vitals:

Center located at 18.6N, 78.8W; maximum sustained winds of 65mph; moving WNW @ 8mph; minimum pressure of 988mb.

Gustav should strengthen to hurricane status sometime today.  There were readings yesterday even while over Jamaica that Gustav could have wobbled around that threshold, but the NHC decided to stick with a Tropical Storm designation.  Regardless, Gustav should assume a more northwesterly heading by the end of the day, takind aim at Cuba’s west coast tomorrow afternoon/evening as a Category 2 storm.  By Sunday morning, Gustav should enter the Gulf of Mexico, regardless of whether he makes landfall over Cuba or not.  Further strengthening is forecasted throughout this time frame and by the time we wake up Sunday, Gustav could be a Category 3 storm (major hurricane).  By Monday morning, Gustav should be taking aim at a smaller portion of the Gulf Coast.  It really won’t be apparent where he should make landfall until Sunday/Monday.

Gustav’s track should take him just to the right of the warmest portion of the large extra-warm pool of water that is WNW of Jamaica, the Gulf Loop Current.  Despite missing the warmest portion of the pool, Gustav could quickly strengthen over the next 24 hours.  The official track forecast would put Gustav over another very warm pool currently located northwest of Cuba.  That could be the time when we see the most explosive growth of this system, if such a thing does occur.  After passing this pool, there shouldn’t be any other factos that drastically alter Gustav’s strength.  He will of course experience eye-wall replacement cycles, which will cause his intensity to oscillate.  The current official forecast calls for Gustav to make landfall along the Louisiana coast west of the Mississippi River as a Category 3.  But do not be surprised if he is stronger at landfall.  Also, the exact landing site is quite frankly irrelevant.  A storm of this magnitude will affect a large area.

In fact, Louisiana has already declared a state of emergency.  A handful of residents along the Gulf coast have announced that they’re evacuating now, no doubt remembering the chaos of evacuating ahead of Katrina, when it was too late to do so.  If you live along the coast or know someone who does, make sure you’re aware of the development of this system.  It has the potential for significant to catastrophic damage.  Stock up on food, water and other emergency supplies now.

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Atlantic Tropical Weather Update 7/20/08

Well, systems are starting to come together after a long stretch of non-genesis.  Yesterday, Tropical Storm Cristobal formed off the South Carolina coast.  Today, Tropical Storm Dolly formed in the western Caribbean.  Meanwhile, Betsy has been downgraded to a Tropical Storm again as she continues to move across the Atlantic.  Let’s take a look at all the vitals:

Betsy: 51.3N, 35.7W; maximum sustained winds of 70mph; moving NE @ 35mph; minimum pressure of 987mb.  Betsy has been caught up in the westerlies.  She has about one day left in her before she interacts with Iceland.  She has had quite the history.

Cristobal: 34.5N, 76.4W; maximum sustained winds of 50mph; moving NE @ 6mph; minimum pressure of 1007mb.  Cristobal is having slight impacts on South and North Carolina’s coasts.  Some rains have been heavy at times as well as convective cells move inland due to Cristobal.  Cristobal’s movement should remain toward the north-east.  His speed will increase as a mid-level trough accelerates him in front of it.  I still expect, as does the NHC, Cristobal to impact Newfoundland sometime Tuesday.

Dolly: 18.4N, 84.2W; maximum sustained winds of 45mph; moving NW @ 17mph; minimum pressure of 1011mb.  Dolly is forecasted to move across the Yucatan Peninsula (not Belize, as I had misidentified earlier) probably later tonight.  She is expected to re-emerge over the Gulf of Mexico Monday during the day.  Thereafter, the track becomes important but highly variable.  There is a small chance Dolly could track a little more north thanf west and impact southern Texas.  Most model solutions keep Dolly further to the south and give Dolly a second landfall over Mexico.

The National Hurricane Center is also keeping an eye on a small area of low pressure 325 south-east of Bermuda.  Development is not expected to take place due to inhibatory environmental factors.  Another tropical wave is emerging form over Africa.  It is broad and disorganized, but will keep an eye on it as it makes its way across the Atlantic.

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Atlantic Tropical Weather Update 7/19/08

How ironic is it that I wrote about unexpected things happening in the tropics two days ago? Tropical Storm Bertha regained Category 1 hurricane strength yesterday. She maintains that strength today as she continues to spin away in the middle of the Atlantic. Remember, this storm formed on July 3rd, or 16 days ago. Cape Verde storms are more likely to be long-lived.

Invest-95 is no more, having moved over Nicaragua and Central America yesterday.

Invest-96 has organized more over the last day and has recognized as Tropical Depression 3 for the 2008 Atlantic season. It could organize further into Tropical Storm Cristobal later today. It has affected South Carolina with heavy rains and increased beach surf. It will continue to affect North Carolina today. Track forecasts vary: it could move over North Carolina or stay out to sea and continue to gather strength and organization. Keep an eye out if you’re in that part of the country.

Invest-94 has moved further across the Caribbean. I really expected this system to form into a T.D. or T.S. by now. It still has a high likelihood of doing so. For what it’s worth, the track forecast continues to show it moving across Belize and into the Bay of Campeche in the extended time-frame.


[Update 1:30P CDT]:

Tropical Storm Cristobal has formed off the coast of the United States. It is centered at 32.8N, 78.3W; maximum sustained winds of 40mph; moving NE @ 7mph; minimum pressure of 1007mb.

Cristobal is still expected to move toward the north-east and affect South and North Carolina over the next couple of days. He will affect the northeastern United States thereafter, while continuing to move out over the open Atlantic. Newfoundland, Canada could be impacted in the extended future (>5 days).

So far, three storms this year.

Invest-94 continues to have winds that keep it just under Tropical Storm strength.

Bertha has maintained Hurricane strength, even though she is more than 40N (higher latitude than Denver, CO) and is over cooler waters.  She should become extratropical in a day or so.

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Atlantic Tropical Weather Update 7/18/08

Invest-94 looks better organized this morning than it did last night. Satellite imagery is pretty impressive. The NHC is giving it a high likelihood of developing into a Tropical Depression again today. It’s life-cycle across the Atlantic has been characterized by a cyclical chance of further development. It has winds at just below Tropical Storm strength. If a central area of closed low pressure develops, we’ll see T.S. Cristobal. Its forecasted path would take it over or just to the north-east of Belize into the Gulf of Mexico. This is one system that bears further watching.


[Update 11:30A CDT]:

The NHC released a special tropical disturbance statement about an hour ago.  Invest-94 and Invest-96 could become tropical depressions or storms later today.  They’re sending a hurricane hunter later this afternoon to Invest-94, centered about 400 miles south-east of Jamaica to determine its organization.  A second hunter is also scheduled to take a look at Invest-96 this afternoon.  This system would have a more immediate effect on the U.S. as its just off-shore from Georgia and South Carolina.  Heavy rains would be the primary threat.  So we could see T.S. Cristobal and T.S. Dolly form shortly.

Bertha continues to spin in the Atlantic and won’t have a direct affect on land for some time.

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Tropical Storm Bertha Update & Tropical Atlantic Overview 7/17/08

This year’s Atlantic tropical season to date is one reason why I love weather: things never happen quite the way you expect them to.  Between Bertha and a few other areas of interest, things keep changing.

Okay.  Bertha is still northeast of Bermuda, just sort of spinning away.  She was centered at 34.2N, 57.4W this morning.  Her movement is ESE @ 9mph, with maximum sustained winds of 60mph and an estimated minimum pressure of 997mb.  Nothing exciting, and not too much has changed since yesterday.

There are officially three Invest storms in the Atlantic right now.  I’ve been writing about Invest-94 as it has made its way across the Atlantic.  I really expected this storm to get its act together by now, but it just hasn’t happened.  It’s in the Caribbean, it still has convection associated with it.  It just hasn’t gotten organized.  As of this afternoon, it’s less likely to get organized than it was yesterday afternoon.  This system should move northwesterly across the Caribbean and impact Belize later this week or early next week.  Whether it’s a Tropical Depression or Storm or anything else at that point is way up in the air.  But even lots of rain can cause destruction.

Invest-95 is the system further west, and is about to affect Nicaragua.  It has a broader area of convection, but is similarly having trouble getting organized, thought that’s mostly due to interactions with land to its west as it spins over warm water.

The third system is now Invest-96.  It is associated with an upper level low that is slowly moving toward the east.  This system moved over Florida yesterday and is sitting just off the East Coast as it meanders toward the north, north-east.  My thoughts with this system is interaction with the mainland U.S. should prevent tropical development, but we’ll see how it turns out.