December weather forecast
Mumbai, India

December marks the onset of the winter season in Mumbai. The drop in temperature to a low of 18.6°C (65.5°F) indicates a cozy chill in the air. The city experiences minimal rainfall of 5mm (0.2") making it a suitable time for vacationers and locals to delight in outdoor recreational activities. The city is abuzz with yuletide celebrations and the beginning of the festive season. As December progresses, the temperatures fall further, welcoming the New Year with cooler days and nights.

Temperature

The start of December sees the average high-temperature at a still hot 32°C (89.6°F), showing little difference from November's 33.5°C (92.3°F). Mumbai experiences a consistent, yet significant, drop from daily highs to a low-temperature of 18.6°C (65.5°F) throughout December.

Heat index

The heat index in December is appraised at a scorching 40°C (104°F). Take more caution, heat exhaustion and heat cramps may occur. Long-lasting activity may cause heatstroke.
Bear in mind that the heat index values are determined for shaded areas and light breezes. Direct sunlight might lead to a heat index increase by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', arises from combining readings of air temperature and relative moisture content. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. Keep it in mind, direct sunlight can augment the heat you experience, possibly pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Youngsters often neglect the necessity for rest and hydration. Thirst is a sign of advancing dehydration - thus the importance of maintaining hydration, specifically during long-lasting physical activities.
The physiological way the human body responds to excessive heat is by inducing perspiration, using sweat evaporation as a cooling mechanism. An upsurge in relative humidity affects normal body cooling mechanisms by slowing evaporation, hence reducing the rate at which the body cools and intensifying the perception of heat. When the body's heat gain surpasses its removal capacity, body temperature starts to climb, leading to potential heat-related ailments.

Humidity

The average relative humidity in December is 69%.

Rainfall

In Mumbai, India, in December, it is raining for 0.4 days, with typically 5mm (0.2") of accumulated precipitation. Throughout the year, there are 78.9 rainfall days, and 2258mm (88.9") of precipitation is accumulated.

Sea temperature

In Mumbai, the average seawater temperature in December is 27°C (80.6°F).
Note: Water temperatures ranging between 25°C (77°F) and 29°C (84.2°F) are regarded as very warm, making swimming, diving, and similar water activities pleasurable for extended periods.

Daylight

With an average of 11h and 0min of daylight, December has the shortest days of the year in Mumbai.
On the first day of December, sunrise is at 6:55 am and sunset at 5:59 pm. On the last day of the month, sunrise is at 7:11 am and sunset at 6:11 pm IST.

Sunshine

In Mumbai, the average sunshine in December is 8.2h.

UV index

December is the month with the lowest UV index in Mumbai, with an average maximum UV index of 7. A UV Index reading of 6 to 7 represents a high health hazard from exposure to the Sun's UV rays for average individuals.
Note: A typical high UV index of 7 in December suggests the following recommendations:
Ward off overexposure. Defence against solar harm is crucial. Remember that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. Make an effort to avoid direct sun exposure during these hours. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage. Beware! Reflecting off water and sand, UV rays are much stronger.