December weather forecast
Montevideo, Uruguay

December puts forward Montevideo's summer with longer sun-filled days and warm sea temperatures. A peak sea temperature of 21.9°C (71.4°F) invites locals and tourists to enjoy beach activities. Gradual decrease in rainfall to 84mm (3.31") announces the holiday season with clear skies. With the longest day and sunshine durations, festive outdoor events are a common sight. Despite the heat, a relative humidity of 67% makes the overall climate quite comfortable.

Temperature

The arrival of December brings an average high-temperature of a still warm 26.5°C (79.7°F), nearly identical to November's 23.7°C (74.7°F). In the month of December, Montevideo's average low-temperature falls to a refreshing 16.3°C (61.3°F).

Humidity

With an average relative humidity of 67%, December is the least humid month.

Rainfall

In Montevideo, Uruguay, in December, it is raining for 6 days, with typically 84mm (3.31") of accumulated precipitation. Throughout the year, there are 77 rainfall days, and 1101mm (43.35") of precipitation is accumulated.

Sea temperature

In Montevideo, in December, the average water temperature is 21.9°C (71.4°F).
Note: For most, swimming in 21.9°C (71.4°F) is not an enjoyable activity. Furthermore, controlling your breathing becomes progressively more difficult as the water temperature decreases from 21°C (69.8°F) to 15°C (59°F).

Daylight

With an average of 14h and 30min of daylight, December has the longest days of the year.
On the first day of December in Montevideo, sunrise is at 05:23 and sunset at 19:43. On the last day of the month, sunrise is at 05:34 and sunset at 20:01 -03.

Sunshine

In December, the average sunshine is 9.2h.

UV index

The months with the highest UV index in Montevideo are January and December, with an average maximum UV index of 12. A UV Index reading of 11, and higher, represents an extreme health hazard from exposure to the Sun's UV radiation for average individuals.
Note: In December, the UV index of 12 transforms into the following advice:
Ensure every crucial precaution is taken. Individuals with light skin could experience burns in under 5 minutes. The hours from 10 a.m. to 4 p.m. have the most intense UV radiation. As much as possible, limit direct sun exposure during this period. Opt for tightly woven and loose clothing to enhance protection from the Sun. When outdoors, it's wise to limit direct sunlight exposure, especially if you have sensitive skin. Always use sunscreen with a minimum 30 SPF. Attention! UV radiation is ramped up when reflecting off sand and water surfaces.