September weather forecast
San Isidro, Philippines

The first month of the autumn, September, is a hot month in San Isidro, Philippines, with an average temperature fluctuating between 23.1°C (73.6°F) and 30°C (86°F).

Temperature

Upon the beginning of September, San Isidro's high-temperatures register at a tropical 30°C (86°F), closely mirroring the preceding month. An average low-temperature of 23.1°C (73.6°F) is common during the nights of September.

Heat index

For September, the heat index is computed to be a very hot 39°C (102.2°F). Adopt extra preventive measures, the occurrence of heat cramps and heat exhaustion is likely. Heatstroke may follow extended activity.
Know that the heat index computations account for shaded terrains and slight winds. Heat index values may be hiked up by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'felt air temperature' or 'real feel', evaluates the perceived heat by adding the effect of moisture in the air. A person's impression of weather can be shaped by several aspects, among them metabolic variations, pregnancy, and levels of physical activity. Recognize that direct exposure to the sun can escalate the heat effect, potentially adding 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are quite important for children. Typically, children face more danger than adults as they usually perspire less. Their larger skin surface relative to their small bodies and increased heat output from their activities enhance their risk.
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. If the body retains more heat than it can expel, the increasing temperature can lead to heat-related conditions.

Humidity

August and September, with an average relative humidity of 86%, are the most humid months.

Rainfall

In San Isidro, in September, it is raining for 29 days, with typically 259mm (10.2") of accumulated precipitation. In San Isidro, during the entire year, the rain falls for 252.9 days and collects up to 1795mm (70.67") of precipitation.

Daylight

In September, the average length of the day in San Isidro is 12h and 13min.
On the first day of September in San Isidro, sunrise is at 5:43 am and sunset at 6:08 pm. On the last day of the month, sunrise is at 5:46 am and sunset at 5:46 pm PST.

Sunshine

The average sunshine in September is 8h.

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 reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for average individuals.
Note: A typical high UV index of 6 in September suggests the following recommendations:
Employ safeguards and advocate sun safety protocols. Shielding against skin and eye damage is crucial. Avoid direct Sun exposure and stay in the shade between 10 a.m. and 4 p.m., a time when UV radiation is most intense, noting that not all shade structures offer full protection. During bright days, sunglasses that offer UVA and UVB defense are recommended.