Weather in Mérida in December

Prime time. December is about as good as Mérida gets. Highs average 29.5 °C, lows 19.4 °C, and rain falls on 6 days — nothing in the month is working against you.

December ranks 2 of 12 in Mérida. Only January scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 6 days, so an itinerary with no wet-weather fallback is a reasonable risk. Pack for 29.5 °C days and 19.4 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 15 days top 30 °C — hot spells arrive, but they break. Across the twenty years measured, the hottest December day reached 35.5 °C and the coldest night fell to 11.8 °C, and the wettest single day dropped 36 mm — roughly 103% of the month's rain in one day.

This is the volatile part. December rainfall has ranged from 4 mm to 122 mm across the twenty years measured — a 118 mm spread around an average of 35 mm. The average is real but almost no individual December looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind is light at 0.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 73%.

How December sits in the year

Temperatures hold steady either side: 29.3 °C in November, 29.5 here, 29.2 in January. Nothing about the timing within the month matters much.

Daylight in December

December sits at the dark end of Mérida's year — 10.9 hours of daylight against 13.4 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 25.2 °C in December — warm enough to stay in as long as you like. The sea peaks at 29.1 °C in August and bottoms out at 24 °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 Mérida versus nearby

If Mérida is one option among several, the nearby comparison is worth making. Cancún is close enough to be a coin toss — 2.7 °C cooler, 5 days more rain. Key West is a better bet in December — 5.4 °C cooler, 1 day more rain.

So: December is effectively as good as it gets here — 1 points behind January, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Mérida

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