December weather forecast
San Isidro, Philippines

The first month of the winter, December, is still a warm month in San Isidro, Philippines, with temperature in the range of an average low of 21.7°C (71.1°F) and an average high of 29.5°C (85.1°F).

Temperature

San Isidro commences December with an average high-temperature of a moderately hot 29.5°C (85.1°F), maintaining a close resemblance to the previous month. Throughout the month of December, the average temperature in San Isidro dips to an agreeable 21.7°C (71.1°F) at night.

Heat index

The average heat index in December is computed to be a torrid 36°C (96.8°F). Take extra precautions, as heat cramps and heat exhaustion are possible. Sustained activity may result in heatstroke.
Given the heat index, its values are aligned with shaded sites and gentle winds. Uninterrupted exposure to the sun may boost the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. An individual's perception of weather can be swayed by a variety of elements including metabolic differences, pregnancy status, and their level of physical exertion. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially vital to children. Children often lack awareness of the importance of taking breaks and rehydrating. The feeling of thirst is a late indication of dehydration, so maintaining hydration, especially during long periods of physical activity, is critical.
Perspiration is essential for the human body; it facilitates cooling through the process of sweat evaporation. Elevated relative humidity disrupts typical body cooling by reducing the evaporation rate, consequently decreasing the body's cooling rate and enhancing the feeling of heat. When heat uptake goes beyond the body's cooling mechanisms, there's a surge in body temperature, posing health risks.

Humidity

In December, the average relative humidity in San Isidro is 81%.

Rainfall

In San Isidro, in December, during 16.4 rainfall days, 89mm (3.5") of precipitation is typically accumulated. Throughout the year, in San Isidro, there are 252.9 rainfall days, and 1795mm (70.67") of precipitation is accumulated.

Daylight

With an average of 11h and 12min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 6:06 am and sunset at 5:24 pm. On the last day of December, in San Isidro, sunrise is at 6:22 am and sunset at 5:36 pm PST.

Sunshine

In San Isidro, the average sunshine in December is 6.5h.

UV index

January, July, September through December, with an average maximum UV index of 6, are months with the lowest UV index in San Isidro. A UV Index value of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV rays for the average person.
Note: The daily high UV index of 6 in December translates into this advice:
Act on precautions and pay attention to sun safety recommendations. Avoidance of sunburn is obligatory. Minimize exposure to direct sunlight and seek shade from 10 a.m. to 4 p.m., when UV radiation is most intense, but remember that shade structures may not offer complete protection. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.