Isaac is still a tropical storm as of 28/03Z located about 260 miles south southeast of Gulfport, Mississippi, and moving to the northwest at 9 knots with sustained winds of 60 knots and a central pressure of 979MB. The core has again been disrupted by dry air entrainment and an eyewall which formed earlier this evening is now open in places according to earlier Recon reports, but as it has in the past, Isaac will like strengthen again later tonight.

NHC projects landfall as a strong Cat I which seems reasonable if the cyclone can shunt off the entrainment. The strong ridge influence of 24 hours ago is probably not as significant a player tonight. Earlier this evening pressure falls along the Florida and Georgia east coast suggested that the Atlantic ridge was not able to build further west - perhaps because of the vorticity maxima that was associated with the breakaway feeder band that moved across the Florida east coast on Monday (and I think directly linked to one of the rotating vortexes that we watched for a couple of days). This should all translate to a more north northwesterly and eventually northerly movement in the next 24 hours with landfall Tuesday evening along the Mississippi coast. BUT given the nature of tropical cyclones in general - especially those in the Gulf of Mexico - and Isaac's history in particular, you indeed do not want to focus on the centerpoint of the projected path but instead, the entire hurricane warning area. Isaac will be a slow moving system as it approaches the coast so those folks in the warning areas can expect high winds, heavy rains and storm surge for a considerably long duration. If you live near the coastline and are ordered to evacuate, please use common sense and do so.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...As of 28/03Z:

A HURRICANE WARNING IS IN EFFECT FOR...
* EAST OF MORGAN CITY LOUISIANA TO THE ALABAMA-FLORIDA BORDER...
INCLUDING METROPOLITAN NEW ORLEANS...LAKE PONTCHARTRAIN...AND LAKE MAUREPAS

A HURRICANE WATCH IS IN EFFECT FOR...
* INTRACOASTAL CITY TO MORGAN CITY LOUISIANA

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* FROM THE ALABAMA-FLORIDA BORDER TO THE AUCILLA RIVER
* INTRACOASTAL CITY TO MORGAN CITY LOUISIANA

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* EAST OF SABINE PASS TO WEST OF INTRACOASTAL CITY LOUISIANA

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