LRandyB's Tropical Weather Discussion

Last Updated: 5:18 PM GMT on August 27, 2012 — Last Comment: 12:44 PM GMT on September 14, 2012

	Tropical Weather Discussion - Friday, August 26, 2011

Posted by: LRandyB, 9:33 PM GMT on August 21, 2011

I'm back from St. Croix after two weeks there and a week and half of flying Irene. The Hurricane Hunters haver pulled their crews out of St. Croix, brought them home to Biloxi, pulled in some fresh crews, and are deploying to Savannah, GA to continue flying Irene for the next day or so until she makes landfall in New England. I'll focus solely on Irene for this discussion.

The 5pm advisory for Irene put the storm at 265 miles SSW of Cape Hatteras, NC moving N at 14 mph. Maximum winds were at 100 mph and central pressure was at 951mb. Irene has weakened slightly today but is still a powerful hurricane. There are two factors that make this storm particularly dangerous. One is the size of the wind field. The Hurricane Hunters are measuring tropical storm force winds as far out as 250 miles on the east side of the storm. The second factor is that these storms do not often strike New England. Because of that, many residents in the New England areas affected by this storm may not take it as seriously as they should. This will prove to be a very significant storm for everyone from NC to ME. I would urge folks in this region to take every precaution in preparation for this storm.

The models are all in very good agreement on the track of Irene. A trough approaching the eastern half of the US is pulling Irene northward now and a turn toward the NNE is expected tonight. This will allow Irene to run along the east coast. As it approaches NY, it's not expected to accelerate as much as systems often do at this stage and so will pound the New England coastline from NJ to MA with heavy rains and tropical storm to occasionally hurricane force winds for an extended period of time as it traverses the region. This will be made worse by the extend of tropical storm force winds east of the center. This will mean that even though the center of the storm will be well inland over western MA by late Saturday night, Boston will likely still see tropical storm force winds with this system. By late Monday Irene should be well north of the New England into Canada as a tropical storm.

Current satellite shows a lot of dry air west of Irene and that is helping to impede any strengthening. Also stronger SW winds aloft ahead of the approaching trough is helping to create some increased shear over the system.

These factors are combining to weaken the system, somewhat, which is a blessing since it means that Irene will likely not make landfall in NC as a major Cat 3 storm. In fact, the official NHC forecast has it down to a cat 1 by landfall in NC early Sat morning.

We'll keep watching Irene over the next 72 hours as she makes her way up the east coast.

For those with iPhone, iPod Touches, and iPad's, there is a new app on the App store designed to help track the Hurricane Hunter flights and all the storms in the Atlantic. It's the first app I have seen that plots the flight tracks and the data generated by the flights.

http://itunes.apple.com/us/app/hurricanehunterapp colallc/id456831217?mt=8

Give it a try. And let me know what you think (No, it's not my app but I know the creators).

Stay safe.

Randy

I'm posting some pictures from my hotel as we wait it out. I'll post again after we fly Irene in the morning by which time NHC expects Irene to be a hurricane.

Randy

TS Irene