A tropical wave moved off the west coast of Africa on September
29th. The wave migrated into the eastern
Caribbean on October 5th. Shower activity was enhanced by an upper trough to its west, spurring heavy
rains and mudslides over Puerto Rico between October 5th and 8th. Below are the graphics showing the rainfall
totals for Puerto Rico and the U.S. Virgin Islands. Data was provided by the National Climatic Data Center
in Asheville, North Carolina.
The area of disturbed weather over the Greater Antilles moved
developing a weak low pressure area
near Hispaniola which became a tropical depression on the 7th. The depression moved northward around the
western edge of the subtropical ridge. A nearly ship reported gale force winds, and Isabel was named. On
the 8th, Isabel reached its peak intensity before interacting with a frontal zone and strong southwesterlies aloft.
The high behind the front bridged across to the subtropical ridge, moving Isabel more westward. By the
afternoon of the 9th, Isabel had lost much of its convection as it neared the Southeast. The cyclone weakened
to a tropical depression as it made a brief landfall in Georgia, before a cold front to the west steered Isabel
northeasterly offshore the Carolinas. Its track lies below, provided by the National Hurricane Center.
Below are the storm total rainfall maps for Isabel. Since the cyclone came ashore as no more than an
exposed low-level cumulus swirl, precipiation amounts were relatively light.