Yes, fronts would be my primary weather
concern. But if you play them right they can also work to your advantage by shifting prevailing winds. The ugly weather
will be at the leading edge of the front. You can hole up somewhere for that to pass and then catch the shift on the trailing edge with more stable weather, but maybe some leftover sloppy seas.
Maybe "most" fronts don't push that far south in December, but plenty do, and its typically the stronger ones.
I worked for years in the charter
industry in Belize
and we would get cold fronts pushing down from the USA from December to as late as March. In 2011 we had fronts thru the entire month of March. The ideal time to transit the GOM is April-May. Its after cold front season and before hurricane
To access the risk you need to get familiar with Pilot Charts
, NOAA Synoptic charts
, and maybe a pro weather router like Chris Parker.