According to NDBC Data Buoy 42003 located in the south Gulf at 26.044 N 85.612 W (26°2'38" N 85°36'42" W), the sea water temp at the buoy is 80.2 degrees and could easily support a hurricane.
Here is the url of that buoy:
http://www.ndbc.noaa.gov/station_page.php?station=42003
80F is the minimal threshold to sustain a hurricane. The Gulf buoy near NOLA yesterday was at 77F. If a storm does manage to squeeze through and strike the central Gulf coast or Big Bend, it will not be a serious danger. This season is just about over for the CONUS.
Interesting, the NHC now gives that Cape Verde disturbance a medium chance of developing. It’s pretty late in the season for Cape Verde development.