May weather forecastPerma, MT
May
Weather in May
The last month of the spring, May, is an enjoyable month in Perma, Montana, with temperature in the range of an average low of 36.7°F (2.6°C) and an average high of 61°F (16.1°C).Temperature
The onset of May brings a temperature shift, with the average high-temperature moving from a chilly 48.7°F (9.3°C) in April to a comfortable 61°F (16.1°C). Perma's nighttime temperature in May demonstrates a noticeable plunge to a cold 36.7°F (2.6°C).Humidity
In Perma, the average relative humidity in May is 67%.Rainfall
In Perma, during May, the rain falls for 14.1 days and regularly aggregates up to 1.26" (32mm) of precipitation. Throughout the year, there are 129.9 rainfall days, and 13.5" (343mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, September through December. May is the last month it regularly snows in Perma. During 0.3 snowfall days, in May, Perma aggregates 0.08" (2mm) of snow. Throughout the year, there are 67.1 snowfall days, and 28.27" (718mm) of snow is accumulated.Daylight
In Perma, the average length of the day in May is 15h and 8min.On the first day of the month, sunrise is at 6:20 am and sunset at 8:50 pm. On the last day of May, sunrise is at 5:45 am and sunset at 9:26 pm MDT.
Sunshine
In May, the average sunshine is 10.5h.UV index
In Perma, the average daily maximum UV index in May is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the ordinary person.Note: A typical high UV index of 4 in May suggests the following recommendations:
Heed the precautions - It is counselled to guard against solar damage. To guard against the harmful effects of the Sun, minimize exposure during midday. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Perma, MT
- Average high temperature in May: 61°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is December (28.4°F).
- Average low temperature in May: 36.7°F
The month with the highest average low temperature is August (49.5°F).
The coldest month (with the lowest average low temperature) is December (16.7°F).
Average pressure in May
Perma, MT
- Average pressure in May: 29.96"Hg
The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in May
Perma, MT
- Average wind speed in May: 4.3mph
The windiest month (with the highest average wind speed) is April (4.8mph).
The calmest months (with the lowest average wind speed) are January, August and December (3.9mph).
Average humidity in May
Perma, MT
- Average humidity in May: 67%
The month with the highest relative humidity is January (91%).
The month with the lowest relative humidity is August (49%).
Average rainfall in May
Perma, MT
- Average rainfall in May: 1.26"
The wettest month (with the highest rainfall) is June (2.2").
The driest months (with the least rainfall) are July and August (0.63").
Average rainfall days in May
Perma, MT
- Average rainfall days in May: 14.1 days
The month with the highest number of rainy days is June (15.7 days).
The month with the least rainy days is August (7.4 days).
Average snowfall in May
Perma, MT
- Average snowfall in May: 0.08"
The month with the highest snowfall is February (6.5").
The months with the least snowfall are June, July and August (0").
Average snowfall days in May
Perma, MT
- Average snowfall days in May: 0.3 days
The month with the highest number of snowfall days is December (14.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in May /
Average sunshine in May
Perma, MT
- Average daylight in May: 15h and 6min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in May: 10h and 30min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in May
Perma, MT
- Average sunshine days in May: 15.3 days
The month with the most sunshine days is July (20.8 days).
The month with the least sunshine days is February (11 days).
Average UV index in May
Perma, 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 February and December (UV index 1).
Average cloud cover in May
Perma, MT
- Average cloud cover in May: 33
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in May
Perma, MT
- Average visibility in May: 6mi
The months with the highest visibility are April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).
