, like December
, in Montevideo
, is a moderately hot summer month, with temperature in the range of an average low of 18°C (64.4°F) and an average high of 28.4°C (83.1°F).
The warmest month is January, with an average high-temperature of 28.4°C (83.1°F) and an average low-temperature of 18°C (64.4°F).
The average heat index is appraised at a hot 31.2°C (88.2°F). Exhaustion is likely with prolonged exposure and activity. Sustaining activity may result in heat cramps.
Note that heat index values are valued for light wind and location in the shade. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.Note
: The heat index, also known as 'feels like', 'felt air temperature', 'apparent temperature', or 'real feel', combines air temperature and relative humidity to represent a human perceived temperature equivalent. Additional factors like differences in body mass, height, and shape, metabolic differences, clothing, and activity influence one's weather impression. Bear in mind that direct sunshine exposure increases weather impact, and may raise heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it is vital to remain hydrated, particularly during prolonged physical activities.
In Montevideo, Uruguay, the average relative humidity in January is 68%.
In Montevideo, during 6 rainfall days, 86.8mm (3.42") of precipitation is typically accumulated. Throughout the year, there are 77 rainfall days, and 1101.2mm (43.35") of precipitation is accumulated.
The month with the warmest seawater in Montevideo is January, with an average sea temperature of 24.2°C (75.6°F).Note
: Depending on a person's sensitivity to cold, with regards to sunshine, wind, and air temperature, a quick swim in 24.2°C (75.6°F) water may be enjoyable. (FYI: The official water temperature required for the Olympic swimming competition is 25°C (77°F) to 28°C (82.4°F).)
In January, the average length of the day is 14.2h.
The month with the most sunshine is January, with an average of 9.5h of sunshine.
Months with the highest UV index are January and December, with an average maximum UV index of 12. A UV Index value of 11, and more, symbolizes an excessive health risk from unprotected exposure to the Sun's UV rays for ordinary individuals.Note
: In January, the average maximum UV index of 12 translate into the following recommendations:
Take all necessary precautions, as unprotected skin can burn in minutes. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. A broad-spectrum sunscreen of SPF 30+ should be liberally applied and re-applied every two hours, and immediately after an outdoor workout or a swim. Beware! The reflection of water and sand dramatically increases exposure to the UV rays.