May weather forecast
San Blas, Mexico

The last month of the spring, May, is another tropical month in San Blas, Mexico, with temperature in the range of an average low of 19.5°C (67.1°F) and an average high of 34°C (93.2°F).
The ideal sea water temperature of 27.4°C (81.3°F) and only 1.9 rainfall days, with 3mm (0.12") of accumulated rainfall, makes May the best time for swimming and other water activities.

Temperature

San Blas witnesses the warmest weather in May, with temperatures averaging a high of 34°C (93.2°F) and a low of 19.5°C (67.1°F).

Heat index

In May, the average heat index is appraised at an extremely hot 42°C (107.6°F). Greater safety measures are needed, risk of heat exhaustion and heat cramps is high. Continuous activity might trigger heatstroke.
Evaluating the heat index requires understanding its values in the shade and with gentle winds. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a metric representing the sensation of warmth when air temperature and moisture come together. Physical activity, clothing, and metabolic variations are additional factors that impact an individual's perception of temperature. Direct exposure to the sun's rays can enhance the felt temperature, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. Young ones are generally more prone to risk than adults due to their reduced ability to sweat. Their large skin surface area relative to their diminutive bodies and elevated heat production from their activities further enhance this risk.
The body's inherent cooling system operates through perspiration, wherein evaporating sweat offsets excessive heat. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. Rising body temperatures resulting from an imbalance in heat absorption can lead to potential thermal issues.

Humidity

In May, the average relative humidity in San Blas, Mexico, is 60%.

Rainfall

Months with rainfall are January through March, May through December. May is the first month it rains. Throughout May, in the average 1.9 rainfall days, it receives 3mm (0.12") of precipitation. In San Blas, Mexico, during the entire year, the rain falls for 106.3 days and collects up to 439mm (17.28") of precipitation.

Sea temperature

In May, the average sea temperature is 27.4°C (81.3°F).
Note: For any water activity, the surface water temperatures in the range of 25°C (77°F) to 29°C (84.2°F) are deemed excellent and incredibly pleasant for longer durations.

Daylight

In San Blas, the average length of the day in May is 13h and 10min.
On the first day of May in San Blas, sunrise is at 5:29 am and sunset at 6:26 pm. On the last day of the month, sunrise is at 5:18 am and sunset at 6:39 pm MST.

Sunshine

With an average of 11.9h of sunshine, May has the most sunshine of the year in San Blas.

UV index

May through July, September and October, with an average maximum UV index of 7, are months with the highest UV index in San Blas. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for the ordinary person.
Note: In May, an average UV index of 7 transforms into the following instructions:
Persist with safeguards and heed sun safety doctrines. Keeping sunburn at bay is of prime importance. Avoid exposure to the Sun and try to stay in the shade between 10 a.m. and 4 p.m., when UV radiation is most potent, but be aware that parasols or canopies may not offer full protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Warning! Reflective surfaces like sand and water amplify the Sun's UV radiation.