The highest day temperature in December 2025 was 84°F. The lowest night temperature was 59°F. The average values for day and night temperatures during December were 78.5°F и 75.0°F respectivly.

The average sea surface temperature in December 2025 for Islamorada was 79.3°F. The maximum and minimum values were 76.4°F and 83.2°F respectively.

You can expect various weather conditions during December. Be ready for sunny, cloudy or even gloomy days.

Precipitation total in December for Islamorada is 0.8 in.

The average wind speed in December is 12.7 mph.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Islamorada in December is 6.2 hours.