Following the forecast remarkably well, Gustav continued on his rapid northeasterly course on Wednesday afternoon and Thursday, making landfall on extreme eastern Nova Scotia then southwest Newfoundland as a weak CAT 1 hurricane early Thursday morning. He transitioned to extratropical and was absorbed into the mid-latitude trough just hours after the landfalls. TD9 formed late Wednesday night from that large area of disturbed weather in the central Gulf that I had been mentioning for a few days. Despite poor convective patterns, pressures had dropped persistently, reaching 1001mb by the time it was classified as a TD (very low for that point in its lifetime!). At 09Z today, aircraft recon, buoys, and nearby ships reported that the sustained winds were strong enough to upgrade it to TS Hanna, the 8th named storm of the season. The 12Z advisory places Hanna at 27.0N 88.6W and tracking NW at 7kts (after having been meandering for a while). Intensity is observed to be 40kts and 1002mb. A Tropical Storm Watch is in effect for the eastern half of the Florida peninsula, and a Tropical Storm Warning is in effect from the central FL panhandle over to near New Orleans, LA... see http://www.nhc.noaa.gov/ftp/graphics/AT09/AL0902W.GIF for details. Currently, the convection is all southeast of the low-level center (due to 10-15kt NW vertical shear), which has been exposed during much of Hanna's existence. The forecast is for further strengthening, and for accelerated motion. As the intensity picks up to 50kts, the track should bend more northerly, and the NHC forecast is for landfall near the FL/AL border (although many computer models predict landfall a bit further west, like Gulfport) Saturday around noon local time. The tropical wave that I positioned at 19N 31W in the 9/11 update is now at about 14N 52W (at least that's where the convection is occuring now, the wave itself is much larger and harder to pin down) and becoming better organized as it clears the high-shear zone. It's tracking W at 20kts and has the potential to become TD10 during the weekend. Lastly, there's a tropical wave just exiting the African coast with fairly high, concentrated vorticity that is only in moderate shear. Though it lacks deep convection now, it will be closely watched the next few days.Please visit my tropical Atlantic headquarters.
13 September 2002
Gustav becomes extratropical, Hanna forms, central and eastern Atlantic still interesting.
Posted by at 10:46 AM