Ivan taking aim on Jamaica...

Mighty Hurricane Ivan maintained CAT5 status until 21Z when it was
downgraded slightly to a strong CAT4.  At this very high strength,
intensity fluctuations are perfectly normal as it responds to minor
changes in oceanic heat content and as it undergoes eyewall replacement
cycles.  It now has maximum sustained winds of 130kts and a MSLP of
921mb.  It's 350 miles ESE of Jamaica and is headed WNW at 13kts;
landfall is expected on Jamaica Friday afternoon/evening.  If it does
indeed hit them head-on at CAT4 intensity, it would be devastating. 
Some of you may recall Hurricane Gilbert '88 who hit the island as a
CAT3 and was incredibly destructive.

The forecast calls for maintaining CAT4/5 intensity as it heads over
Jamaica on Friday afternoon, western Cuba on Sunday evening, then
perhaps weaken slightly as it heads for Florida Monday evening or
Tuesday afternoon, depending on how far north it makes it before hitting
land.  Hurricane warnings are in effect for Jamaica and the Cayman
Islands, and Hurricane watches are up for virtually all of Cuba.  No
watches or warnings yet for the US.

In other news, TD10 formed from a tiny weak circulation near the Azores
Islands in the far northeast Atlantic.  It lasted for 12 hours (09-21Z
today) before NHC ceased writing advisories on it.  It was highly
sheared and no longer convectively active.

Please visit my tropical Atlantic headquarters.