WeatherBug Gustav Technical Discussion - 2pm:8/31 Update

Below is an update from our Chief Meteorologist Mark Hoekzema at WeatherBug on Hurricane Gustav and Tropical Storm Hannah from the Hurricane Command Center.

Here are some links to some weather cameras from the WeatherBug Network with a view to what is coming…
- Key West, FL
- Baton Rouge, LA
- Arabi, LA

Gustav a category 3 hurricane but late morning satellite imagery shows some re-organization is occurring. Outer rain bands showing on radar near the mouth of the Mississippi River and off the Gulf Coast of Florida
Over the last 6 hours Gustav continued on a steady and speedy 17 mph pace at a 320 degree heading. A continuation on that heading through to landfall would be a direct hit to New Orleans. At that speed, Gustav would also begin to affect the Louisiana coast earlier than the current forecasts as well. Also, Gustav continues to track slightly right (east) of the going NHC forecast. This has been generally the case for the last 24 hours.
Forecast models and NHC forecasts continue to indicate that the storm will undergo a fade to the west and more of a 300 degree heading that would take the center into Louisiana on the Gulf Coast south of New Orleans. This slow shift in the track should begin to become apparent in the next 6-12 hours and should be watched closely using satellite imagery.
Regardless of the actual landfall position of the center, the Mississippi Delta, including New Orleans will likely be hit by some of the strongest winds that surround the center. At this intensity, damage will be significant and extensive.
Another feature of note is that Gustav has shown some intense flaring of convection this morning on the west and southwest side of the storm. This side has historically been the strongest sector of Gustav and it continues today. In the last several hours though, convection is attempting to get organized all around the eye of the storm and the center has begin going through some organization cycles. NHC Forecasts indicate some re-strengthening to a category 4 hurricane and given the current scenario and environmental conditions it is likely Gustav will spend at least some time as category 4 before landfall.
The overall wind swath radius extends further NE of the center due to the wind speed that is added due to the forward motion of the storm which is significant at 16 mph. Currently, tropical storm force winds extend out nearly 200 miles northeast of the center. This is important for locations that are east/northeast of the center at landfall to follow closely.
The other important aspect of the storm will be the forecasted slowing that is expected to occur after landfall as the storm runs into a strong ridge of high pressure that is building over the southern states. This will cause Gustav to spend several days dumping rain over Louisiana and eastern Texas.
There will be rainfall potential of 5 – 15” of rain in Louisiana, southern Alabama and Eastern Texas with some areas potentially receiving 2 feet of rain over the next week.
At 11am, the center of Gustav was located at 25.3N, 86.0W and 325 miles southeast of the mouth of the Mississippi River. Maximum sustained wind estimates are 120 mph with gusts to 140 mph and a central pressure of 28.41” (962mb).
Pleases refer to WeatherBug News for complete coverage of the storm - http://weather.weatherbug.com/hurricanes/hurricane-Gustav-2008.html

Tropical Storm Hannah drifts slowly west toward the Bahaman Islands

Tropical Storm Hannah has been struggling to maintain its tropical structure over the last 2 days and this is why it continues to be only a moderately strong tropical system. There are indications that the conditions will become more favorable in a couple of days and this could allow for some strengthening by the middle to later part of next week.
Given the slow movement and uncertainty of the physical conditions surrounding the storm, the uncertainty on the forecast track outside the next two days is very high. This storm should be monitored closely over the next 2 days as the future effects and track of the system will become more apparent.
Currently, the odds favor Hannah remaining offshore of the U.S. through the end of the coming week. After that, it is much too far off to say where it might end up and how strong it will be. NHC forecasts indicate a turn to the NW along the Florida coast and some strengthening.
Please refer to WeatherBug News for complete coverage of the storm – http://weather.weatherbug.com/hurricanes/hurricane-Hanna-2008.html
The next WeatherBug Gustav Technical Discussion will be sent at about 5pm Sunday.
- Mark Hoekzema, WeatherBug Chief Meteorologist