Interesting discussion from NWS Key West office:

FLORIDA KEYS AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
500 PM EDT THU JUL 7 2005

.DISCUSSION...
.OBSERVATIONS/TRENDS...
GOES-12 WATER VAPOR IMAGERY SHOWS AN APPARENT MID AND UPPER LEVEL
CYCLONIC CIRCULATION JUST NORTH OF THE BAHAMIAN CHAIN...WHICH
APPEARS TO BE ERODING THE SOUTHERN PORTION OF THE WESTERN ATLANTIC
SUBTROPICAL RIDGE. MEANWHILE...AS THE REMNANTS OF TROPICAL CYCLONE
CINDY EXIT NORTHEASTWARD INTO THE TENNESSEE VALLEY...ANOTHER MID
LATITUDE TROUGH IS DIVING SOUTHEAST INTO THE GULF COAST REGION.
SUBSEQUENTLY...IT APPEARS THE FORMER DISTURBANCE HAS CREATED A
WEAKNESS IN THE SUBTROPICAL ANTICYCLONE ALLOWING HURRICANE DENNIS TO
MIGRATE TOWARD THE NORTHWEST ALL DAY.