May weather forecast
Vientiane, Laos

The weather in May in Vientiane, Laos, continues to intensify, with relatively high temperatures and a considerable increase in rainfall from 85mm (3.35") in April to 246mm (9.69"). A marked increase in humidity accompanies this shift to the monsoon season, with the relative humidity reaching 78%. The lush green scenery after the rain showers leaves Laos at its most beautiful, making it a popular time for photographers and nature lovers to visit. Outdoor exploration, however, requires careful planning due to the heavy rainfall.

Temperature

With the transition into May, Vientiane notes an average high-temperature of a still tropical 33°C (91.4°F), closely resembling April. The mean low-temperature during May nights is a moderately hot 24.6°C (76.3°F).

Heat index

May's heat index is estimated at a burning hot 47°C (116.6°F). Warning: Heat cramps and heat exhaustion are anticipated. Heatstroke is a risk with ongoing activity.
It is emphasized that the heat index's values are meant for shaded zones with mild winds. A rise of up to 15 Fahrenheit (8 Celsius) degrees in the heat index could result from direct sunlight.
Note: The heat index, also known as 'feels like' or 'apparent temperature', stands as a testimony to how temperature and humidity combine to impact our sense of warmth. The experience of temperature can be subjective, varying based on the individual's activity and heat perception, influenced by factors like wind, attire, and metabolic variations. When you're directly under the sun's rays, remember that the heat index may surge by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful for babies and toddlers. In general, younger individuals are at greater risk than adults because they tend to sweat less. Also, having a larger skin surface to body size ratio and greater heat production due to their active behavior contribute to this danger.
Perspiration is essential for the human body; it facilitates cooling through the process of sweat evaporation. Under conditions of increased relative humidity, the evaporation rate lessens, causing the body to retain more heat than under less humid conditions. Excessive heat that's not properly managed leads to increased body temperatures and resultant health issues.

Humidity

In Vientiane, Laos, the average relative humidity in May is 78%.

Rainfall

In Vientiane, in May, it is raining for 15 days, with typically 246mm (9.69") of accumulated precipitation. In Vientiane, during the entire year, the rain falls for 118 days and collects up to 1661mm (65.39") of precipitation.

Daylight

In Vientiane, the average length of the day in May is 12h and 59min.
On the first day of May, sunrise is at 05:42 and sunset at 18:30. On the last day of the month, sunrise is at 05:33 and sunset at 18:41 +07.

Sunshine

In May, the average sunshine is 6.7h.

UV index

March through September, with an average maximum UV index of 12, are months with the highest UV index. A UV Index value of 11, and more, symbolizes an excessive health risk from unsafe exposure to UV radiation for the ordinary person.
Note: The daily high UV index of 12 in May translates into this advice:
Adopt every precaution of necessity, unprotected skin and eyes may suffer burns instantly. Remember that UV radiation from the Sun is strongest between 10 a.m. and 4 p.m. Make an effort to limit direct sun exposure during this time. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection. Directly after swimming or an outdoor workout, generously apply and reapply a broad-spectrum SPF 30+ sunscreen.