Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
The onset of May marks an increase in the average high-temperature, moving from a fresh 55.2°F (12.9°C) in April to an enjoyable 65.8°F (18.8°C). Custer temperatures generally rest at a low of 46.4°F (8°C) during the May nights.Humidity
The average relative humidity in May is 55%.Rainfall
The month with the most rainfall is May, when the rain falls for 14.3 days and typically aggregates up to 1.85" (47mm) of precipitation.Snowfall
Months with snowfall are January through May, September through December. May is the last month it regularly snows. During 0.6 snowfall days, in May, Custer aggregates 0.16" (4mm) of snow. In Custer, during the entire year, snow falls for 48.3 days and aggregates up to 17.68" (449mm) of snow.Daylight
In May, the average length of the day is 14h and 59min.On the first day of May, sunrise is at 5:55 am and sunset at 8:19 pm. On the last day of the month, sunrise is at 5:22 am and sunset at 8:53 pm MDT.
Sunshine
In May, the average sunshine is 10.1h.UV index
In Custer, the average daily maximum UV index in May is 5. A UV Index of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the average person.Note: The daily high UV index of 5 during May translates into the following recommendations:
Take measures. Individuals with light skin might experience burns in under 30 minutes. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Be alert! Nearly double the UV rays from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Custer in May?
What is the average humidity in May?
What is the rainiest month?
How many days does it rain in May in Custer?
What is the last month it snows?
What is the average length of the day in May?
What time are sunrise and sunset in May?
How long on average sun shines in May?
What is the UV index reading in May?
Average temperature in May
Custer, MT
- Average high temperature in May: 65.8°F
The warmest month (with the highest average high temperature) is July (86.5°F).
The months with the lowest average high temperature are January and December (31.1°F).
- Average low temperature in May: 46.4°F
The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (17.6°F).
Average pressure in May
Custer, MT
- Average pressure in May: 29.91"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).
Average wind speed in May
Custer, MT
- Average wind speed in May: 9.9mph
The windiest month (with the highest average wind speed) is April (10.2mph).
The calmest months (with the lowest average wind speed) are July and August (8.2mph).
Average humidity in May
Custer, MT
- Average humidity in May: 55%
The month with the highest relative humidity is January (79%).
The month with the lowest relative humidity is August (38%).
Average rainfall in May
Custer, MT
- Average rainfall in May: 1.85"
The wettest month (with the highest rainfall) is May (1.85").
The driest month (with the least rainfall) is December (0.55").
Average rainfall days in May
Custer, MT
- Average rainfall days in May: 14.3 days
The month with the highest number of rainy days is May (14.3 days).
The month with the least rainy days is December (4.5 days).
Average snowfall in May
Custer, MT
- Average snowfall in May: 0.16"
The month with the highest snowfall is February (4.29").
The months with the least snowfall are June, July and August (0").
Average snowfall days in May
Custer, MT
- Average snowfall days in May: 0.6 days
The month with the highest number of snowfall days is February (10.6 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in May /
Average sunshine in May
Custer, MT
- Average daylight in May: 15h and 0min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in May: 10h and 1min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 12min).
Average sunshine days in May
Custer, MT
- Average sunshine days in May: 14 days
The month with the most sunshine days is November (19.2 days).
The month with the least sunshine days is April (13.5 days).
Average UV index in May
Custer, MT
- Average UV index in May: 5
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in May
Custer, MT
- Average cloud cover in May: 34
The month with the most cloud cover is February (Cloud cover 46).
The months with the least cloud cover are July and August (Cloud cover 15).
Average visibility in May
Custer, MT
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Custer, Montana, USA
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