Weather in Jacksonville in December

Prime time. December is about as good as Jacksonville gets. Highs average 19.8 °C, lows 8.3 °C, and rain falls on 8 days — nothing in the month is working against you.

December ranks 4 of 12 in Jacksonville: past the worst of the year but short of November, which is the month to book if the dates are open.

Rain on 8 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

Averages flatten a month, and this one hides a few things: it never really gets hot: not one day in an average December reaches 30 °C. Across the twenty years measured, the hottest December day reached 28.4 °C and the coldest night fell to -5.9 °C, and the wettest single day dropped 69 mm — roughly 86% of the month's rain in one day.

December is moderately variable: 17 mm in the driest year against 184 mm in the wettest, around an average of 80 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind is light at 2.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 82%, high enough to notice on the warm days without dominating them.

How December sits in the year

The month is on the way down: 3.1 °C cooler than November, with January dropping another 2.1 °C. The first week and the last are not the same trip.

Daylight in December

December sits at the dark end of Jacksonville's year — 10.2 hours of daylight against 14.1 at midsummer, holding steady all month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

Sea temperature

The sea sits at about 21.6 °C in December — comfortable for a proper swim. The sea peaks at 28.4 °C in August and bottoms out at 19.5 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Peak season. Expect the highest prices of the year and to be booking well ahead.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

December in Jacksonville versus nearby

If Jacksonville is one option among several, the nearby comparison is worth making. Tallahassee is the weaker option in December — within a degree on temperature, 2 days more rain. Tampa is close enough to be a coin toss — 2.4 °C warmer, 1 day less rain.

So: December is effectively as good as it gets here — 4 points behind November, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Jacksonville

See all twelve months in Jacksonville, or where else to go in December.