Late-coming Hurricane Jeanne brought almost 2 feet of rain to the Florida keys and stirred seas to 15 feet before slowing and weakening in the Gulf of Mexico Wednesday. The storm was being held between a powerful high-pressure system to the north and cooler, dry air to the west. Aircraft and satellite information indicated the storm would continue moving west at 5M.P.H. for at least 24 hours. The storm was expected to remain in the gulf through Thursday, with its approximately 75 M.P.H. winds expected to decline.