May weather forecast
San Juan, Philippines

May, the last month of the spring in San Juan, is also a hot month, with temperature in the range of an average high of 32°C (89.6°F) and an average low of 25.3°C (77.5°F).

Temperature

The month of May, characterized by an average high of 32°C (89.6°F) and a low of 25.3°C (77.5°F), is recognized as the warmest.

Heat index

May's mean heat index is calculated to be a blisteringly hot 43°C (109.4°F). Keep alert: Heat cramps and heat exhaustion are probable. Heatstroke is a potential danger with continued physical activity.
Take into consideration that the heat index values are calculated for shade and light wind conditions. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', is a numerical representation of warmth when taking temperature and moisture levels into account. The perception of temperature can be subjective, varying based on activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Considering the impact of direct sunlight, it's possible for the heat index to surge by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Children often do not understand the need to rest and hydrate. Thirst is a late manifestation of dehydration - therefore, it is essential to stay hydrated, particularly during prolonged physical activities.
The evaporation of sweat is a natural cooling mechanism of the human body, facilitated by perspiration. When relative humidity is on the rise, it curtails evaporation, thereby reducing the heat elimination from the body and causing the feeling of being excessively hot. When heat gain surpasses the level the body can shed, body temperature begins to increase, and consequently, overheating and dehydration can occur, with varying severity.

Humidity

The average relative humidity in May is 77%.

Rainfall

In San Juan, Philippines, in May, during 16.6 rainfall days, 51mm (2.01") of precipitation is typically accumulated. In San Juan, during the entire year, the rain falls for 196.1 days and collects up to 602mm (23.7") of precipitation.

Daylight

In San Juan, the average length of the day in May is 12h and 49min.
On the first day of May in San Juan, sunrise is at 5:33 am and sunset at 6:12 pm. On the last day of the month, sunrise is at 5:25 am and sunset at 6:21 pm PST.

Sunshine

In San Juan, the average sunshine in May is 11.1h.

UV index

February through November, with an average maximum UV index of 7, are months with the highest UV index in San Juan, Philippines. A UV Index estimate of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for the ordinary person.
Note: A daily maximum UV index of 7 in May translates into the following instructions:
Avoid excessive sunlight. Those with lighter skin may experience burning in less than 20 minutes. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays.