May weather forecast
Yellowstone National Park, WY

May in Yellowstone National Park brings warmer weather and longer days. The maximum temperature approaches pleasant highs of 51.9°F (11.1°C), making outdoor exploration more enjoyable. Rainfall is at its peak, renewing the park's plentiful flora and enriching the vibrancy of the landscape. Wildlife enthusiasts can witness animals caring for their offspring. Rivers brim with melting snow, attracting waterfowlers eager to return for the season.

Temperature

Yellowstone National Park's weather in May shows a minor rise in the average high-temperature, moving slightly up from April's frosty 43.3°F (6.3°C) to a fresh 52°F (11.1°C). Yellowstone National Park measures a considerable dip from daytime highs with an average low-temperature of 28°F (-2.2°C) during May.

Rainfall

May is the month with the most rainfall. Rain falls for 11.5 days and accumulates 2.48" (63mm) of precipitation.

Snowfall

Months with snowfall in Yellowstone National Park are January through June, September through December. In May, in Yellowstone National Park, it is snowing for 4.4 days. Throughout May, 8.11" (206mm) of snow is accumulated. In Yellowstone National Park, during the entire year, snow falls for 91.4 days and aggregates up to 193.7" (4920mm) of snow.

Daylight

In Yellowstone National Park, Wyoming, the average length of the day in May is 14h and 49min.
On the first day of the month, sunrise is at 6:11 am and sunset at 8:27 pm. On the last day of May, sunrise is at 5:40 am and sunset at 8:59 pm MDT.

Sunshine

In Yellowstone National Park, Wyoming, the average sunshine in May is 9h.

UV index

In May, the average daily maximum UV index in Yellowstone National Park, Wyoming, is 8. A UV Index reading of 8 to 10 represents a very high health risk from exposure to the Sun's UV rays for ordinary individuals.
Note: In May, a daily UV index of 8 turns into the following recommendations:
Ensure you're protected; unprotected eyes and skin can get hurt in moments. Minimize exposure to direct sunlight and seek shade from 10 a.m. to 4 p.m., when UV radiation is most intense, but remember that shade structures may not offer complete protection. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.