Winter in the Caribbean is characterized by a series of cold fronts that burst out and quickly seep down from the hyper-frigid Arctic every couple of weeks or so. The fronts, known locally as "Northers," unload most of their cold fury on the landmass of North America, warm up significantly as they cross over the relatively tepid waters of the Gulf of Mexico, and enter the Caribbean region a mere shadow of their former bone-crackingly cold selves.
The seasonal visits of the Arctic air masses typically begin affecting the Caribbean region in mid October, occur most frequently during the months of December thru February, but can show up as late as March. As mentioned, the bodies of cold air lose a lot of their chill and oomph as they slide into the warmth of southern latitudes, yet upon arrival in the tropics they can (and do) cool ambient temps noticeably (when a Norther is blowing it can get as "cold" as 65 degrees Fahrenheit [18 Celsius] at night here in Roatan). The encounter between the visiting Arctic air and the resident moist, tropical air invariably results in at least a couple of days of rainy, stormy weather as the front moves through.
This winter, the storm events produced by the Northers have been followed by unusually large "invasions" of Sargasso seaweed. Literally, millions of tons of sargasso weeds have been pushed by waves from the winter storms from the Atlantic Ocean into the Caribbean Sea basin (and unto our beaches and seashore). While an unusually high volume of this particular species of seaweed may be a cyclical phenomenon, one can't help but wonder if this strange occurrence isn't yet another eerie 'canary in the mineshaft' result of global climate change.
Paya Bay Resort, Roatan, Bay Islands of Honduras.