Weather in Cancun in December

How December compares

December is the 11th warmest month of the year in Cancun and ranks 35th of 134 destinations we compare for December - see where else is hot in December. Within Mexico it is 5th of 5 (Mexico in December). Against London's average high of 7.7°C in December, Cancun is 18.2°C warmer by day and 20.2°C warmer at night.

Daytime and night-time in December

The typical December day in Cancun peaks at 25.9°C, but that is an average: the warmest 10% of days reach 27.7°C or more. About 76% of days top 25°C. Nights average 22.9°C; one night in ten drops to 20.6°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest December day here reached 29.5°C (2018-12-09) and the coldest night 14.2°C (2018-12-22).

Rain in December

Wet (more than 8 rainy days): about 11 days with 1 mm or more, 53 mm in total. Year to year it varies a lot - the wettest December was 2006 with 160 mm, the driest 2010 with 6 mm. Humidity averages 75%.

Sea temperature in December

The sea averages 26.7°C - warm enough to swim (22°c+). Depending on the year it ranges from 26.1°C to 27.3°C. For the warmest sea here, come in September (28.9°C).

Sunshine and daylight

Around 5.8 hours of sunshine a day (estimated from cloud cover), 10.7 hours of daylight: the sun rises about 07:17 and sets about 18:08 local time in mid-December. Average cloud cover is 46%.

Is December a good time to visit Cancun?

It is a reasonable choice: hot days but expect showers. The best months for Cancun on our scoring are April, March, February; months averaging 25°C or more: Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec.

Warm enough for summer clothes, without fierce heat

Cancun feels substantially warmer than London in December, with average daytime highs 18.2°C higher. Days reach 25°C around 76% of the time, so lightweight clothes are a sensible starting point rather than a hopeful packing choice. Humidity averages 75%, which can make the warmth feel heavier, especially around midday. Choose loose, breathable clothing and leave room for shade breaks. Average night lows of 22.9°C mean evenings generally remain warm, though a light layer gives you flexibility when it feels cooler. This suits travellers who want reliable warmth more than those looking for intense heat throughout their holiday.

Expect sunshine, but leave space for rain

Rain is the main compromise: December has about 11 rainy days, so a completely dry holiday is not something to count on. That does not mean those days are wet throughout, but it does make a rigid outdoor schedule less useful. Bring a lightweight waterproof and keep plans easy to rearrange when rain arrives. Sunshine averages about 5.8 hours within 10.7 hours of daylight, leaving a noticeable gap between available daylight and actual sunshine. Make use of bright spells rather than assuming clear skies will last. December works best if some cloud and interrupted outdoor time would not spoil the trip.

The sea is warm enough to make swimming a priority

With an average sea temperature of 26.7°C, December is comfortably in swimming territory. The year-to-year range of 26°C to 27°C also suggests that sea warmth is a dependable reason to choose this month. For travellers who care more about getting into the water than lying in strong heat, that is a useful balance: warm seas alongside relatively moderate daytime temperatures. Pack swimwear, sun protection and something light to put on afterwards. Water temperature alone does not tell you how calm the sea will be, so warm water should not be taken as a promise of suitable swimming conditions every day.