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 advent of December reveals an average high-temperature of a still warm 26.5°C (79.7°F), showing minimal difference from the prior month. During December, an average low-temperature of 16.3°C (61.3°F) is observed.

Humidity

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

Rainfall

In Montevideo, 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 individuals, swimming in 21.9°C (71.4°F) is not a pleasurable activity. Breathing becomes progressively more difficult as water temperature declines below 21°C (69.8°F).

Daylight

December has the longest days of the year, with an average of 14h and 30min of daylight.
On the first day of December, 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 Montevideo, the average sunshine in December is 9.2h.

UV index

January and December, with an average maximum UV index of 12, are months with the highest UV index in Montevideo. A UV Index value of 11, and more, symbolizes an extreme threat to health from unprotected exposure to Sun's UV rays for average individuals.
Note: The maximum UV index of 12 during December leads to these instructions:
Adopt all important safety measures, unprotected skin may burn rapidly. Make an effort to avoid direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation, and note that objects like parasols or canopies might not offer full sun protection. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. Ward off sunburn by liberally using sunscreen with 30 SPF or more. This also diminishes the Sun's damaging radiation effects on your health. Watch out! Sand and water enhance the UV exposure you receive.