Weather in Mexico in December

December climate overview

Daytime highs across Mexico in December run from 25.9°C (Cancun) to 28.3°C (Puerto Vallarta). In Puerto Vallarta about 94% of December days reach 25°C. Nights average 21.9°C; the coldest 10% of nights in Cancun fall to 21°C or below.

Rainfall in December

Expect around 9 rainy days (1 mm or more) in December, with Puerto Vallarta the driest (3 days) and Tulum the wettest (11 days). The wettest December at Puerto Vallarta between 1991 and 2020 was 2013 with 224 mm; the driest was 2010 with 0 mm.

Sea temperature

The sea averages 26.7°C around Mexico in December - warmest at Tulum (27.2°C). That is comfortable for swimming.

Sunshine and daylight

Around 5.9 hours of sunshine a day on average, out of 10.8 hours of daylight (sunshine estimated from cloud cover).

December against the rest of the year in Mexico

December is the 11th warmest month of the twelve in Mexico. It is 1.0°C cooler than November and 0.5°C cooler in January. The hottest month here is August (30°C) and the coolest January (26°C).

Which part of Mexico in December?

• Most sunshine: Tulum, 6.1 h a day.
• Driest: Puerto Vallarta, about 3 rainy days.
• Warmest sea: Tulum, 27°C.
• Hottest: Puerto Vallarta, 28°C by day.
• Coolest (better for walking and cities): Cancun, 26°C.

What to pack for Mexico in December

Based on the averages: summer clothes for the day; a rain jacket - roughly 9 wet days; swimwear - the sea is 27°C.

Similar weather elsewhere in December

Within 1.5°C of Mexico's December daytime average: Montego Bay (28°C, sea 28°C), Singapore (28°C, sea 28°C), Bali (28°C, sea 29°C), St Lucia (28°C, sea 28°C), Koh Samui (28°C, sea 28°C). See the full ranking for December.

Puerto Vallarta for warmer days and less rain

Puerto Vallarta offers the best balance of daytime warmth and fewer rainy days among these destinations. Its daytime average is 28°C, with 3 rainy days, making it the clearest choice if you want to spend much of your holiday outdoors without planning around wet weather. That does not guarantee an entirely dry stay, but rain is less of a concern here than on the Caribbean coast. The trade-off comes after sunset and in the water: nights average 19°C and the sea is 25°C. Pack light clothes for the day and a light layer for evenings, particularly if you prefer sitting outside.

The Caribbean coast for warmer water and evenings

Cancun, Tulum, Riviera Maya and Playa del Carmen have similar December weather, so temperature alone gives little reason to favour any particular destination. Days average 26°C across them, with sea temperatures of 27°C: a good combination if swimming matters more to you than the highest daytime heat. Evenings stay warm, with nights at 22°C in Tulum, Riviera Maya and Playa del Carmen, and 23°C in Cancun. The catch is a greater chance of rain interrupting outdoor plans. Playa del Carmen averages 10 rainy days, compared with 11 in the others. Keep your plans flexible rather than expecting consistently dry beach weather.