May weather forecast
Chiang Rai, Thailand

The charm of Chiang Rai in May lies in its mixed-interlude of sunshine and rainfall. The city experiences its hottest month, welcoming frequent downpours, marking a transition into the rainy season. These intermittent showers are a refreshing contrast to the high humidity levels. Though sunlight is slightly less in comparison to previous months, it perfectly blends with showers, painting a vibrant picture of the city. May is a time when nature flourishes and the city’s greenery is at its peak.

Temperature

The arrival of May marks a slight shift to an average high-temperature of a still tropical 33.1°C (91.6°F) from April's 34.8°C (94.6°F). Chiang Rai's nights in May experience an average temperature drop to an agreeable 22.5°C (72.5°F).

Heat index

In May, the heat index is appraised at a burning hot 47°C (116.6°F). Be on the lookout: Heat cramps and heat exhaustion are anticipated. Continued exertion can result in heatstroke.
For clarity, heat index numbers account for light winds and areas under shade. Heat index values can rise by 15 Fahrenheit (8 Celsius) degrees when in direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'feels like', provides an understanding of perceived warmth by combining temperature and relative humidity. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Exposure to direct sun rays can influence the heat you feel, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Children frequently underestimate the necessity to rest and hydrate. Thirst is a late sign of dehydration - thus, it is vital to stay hydrated, particularly during lengthy physical exercises.
The physiological way the human body responds to excessive heat is by inducing perspiration, using sweat evaporation as a cooling mechanism. When there is an excess of moisture in the atmosphere, the efficiency of the evaporation process is lessened, leading to less efficient body cooling and a sensation of overheating. Heat-related disorders may develop if heat gain in the body overshadows its cooling capacity, leading to elevated temperatures.

Humidity

In May, the average relative humidity is 76%.

Rainfall

In Chiang Rai, in May, during 17 rainfall days, 213mm (8.39") of precipitation is typically accumulated. Throughout the year, there are 137 rainfall days, and 1691mm (66.57") of precipitation is accumulated.

Daylight

In May, the average length of the day in Chiang Rai is 13h and 5min.
On the first day of the month, sunrise is at 05:51 and sunset at 18:44. On the last day of May, sunrise is at 05:40 and sunset at 18:55 +07.

Sunshine

In Chiang Rai, the average sunshine in May is 7h.

UV index

The months with the highest UV index are March through September, with an average maximum UV index of 12. A UV Index reading of 11, and higher, represents an ultimate health vulnerability from exposure to the Sun's UV rays for average individuals.
Note: In May, a daily maximum UV index of 12 leads to the following instructions:
Adopt every vital precaution, unprotected skin and eyes may burn rapidly. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Broad-spectrum sunscreen with an SPF of 30 or more should be applied liberally every two hours and directly after outdoor activities or swimming.