May weather forecastHeron, MT
May
Weather in May
May, the last month of the spring in Heron, is a refreshing month, with an average temperature ranging between min 37.9°F (3.3°C) and max 61.3°F (16.3°C).Temperature
May's onset brings a rise in the average high-temperature, moving from a frosty 48.7°F (9.3°C) in April to a refreshing 61.3°F (16.3°C). Significant dips from daytime highs mark the May nights, with a consistent average temperature of 37.9°F (3.3°C).Humidity
In May, the average relative humidity is 69%.Rainfall
In Heron, Montana, in May, it is raining for 17.2 days, with typically 2.4" (61mm) of accumulated precipitation. In Heron, during the entire year, the rain falls for 161.9 days and collects up to 27.48" (698mm) of precipitation.Snowfall
Months with snowfall are January through May, September through December. May is the last month it regularly snows. During 0.3 snowfall days, in May, Heron aggregates 0.04" (1mm) of snow. Throughout the year, there are 80.8 snowfall days, and 60" (1524mm) of snow is accumulated.Daylight
In Heron, the average length of the day in May is 15h and 13min.On the first day of May, sunrise is at 6:23 am and sunset at 8:57 pm. On the last day of the month, sunrise is at 5:48 am and sunset at 9:35 pm MDT.
Sunshine
In May, the average sunshine is 9.8h.UV index
In May, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: In May, the maximum UV index of 4 translates into these guidelines:
Preventative actions are necessary - Recommendations to ward off sunburn are given. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Heron, MT
- Average high temperature in May: 61.3°F
The warmest month (with the highest average high temperature) is August (78.3°F).
The month with the lowest average high temperature is December (29.3°F).
- Average low temperature in May: 37.9°F
The month with the highest average low temperature is August (49.1°F).
The coldest month (with the lowest average low temperature) is December (18.7°F).
Average pressure in May
Heron, MT
- Average pressure in May: 29.95"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The months with the lowest atmospheric pressure are June and August (29.92"Hg).
Average wind speed in May
Heron, MT
- Average wind speed in May: 4.3mph
The windiest month (with the highest average wind speed) is April (4.5mph).
The calmest month (with the lowest average wind speed) is December (3.5mph).
Average humidity in May
Heron, MT
- Average humidity in May: 69%
The month with the highest relative humidity is January (94%).
The month with the lowest relative humidity is August (52%).
Average rainfall in May
Heron, MT
- Average rainfall in May: 2.4"
The wettest month (with the highest rainfall) is December (3.66").
The driest month (with the least rainfall) is August (0.55").
Average rainfall days in May
Heron, MT
- Average rainfall days in May: 17.2 days
The month with the highest number of rainy days is April (19.3 days).
The month with the least rainy days is August (6.9 days).
Average snowfall in May
Heron, MT
- Average snowfall in May: 0.04"
The month with the highest snowfall is January (15.87").
The months with the least snowfall are June, July and August (0").
Average snowfall days in May
Heron, MT
- Average snowfall days in May: 0.3 days
The month with the highest number of snowfall days is December (19.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in May /
Average sunshine in May
Heron, MT
- Average daylight in May: 15h and 12min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in May: 9h and 48min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 12min).
Average sunshine days in May
Heron, MT
- Average sunshine days in May: 11.8 days
The month with the most sunshine days is July (20.9 days).
The month with the least sunshine days is March (7.1 days).
Average UV index in May
Heron, MT
- Average UV index in May: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in May
Heron, MT
- Average cloud cover in May: 36
The month with the most cloud cover is January (Cloud cover 67).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in May
Heron, MT
- Average visibility in May: 6mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (3mi).
