Dillon Weather in May
Average highs run from 59°F on May 1 to 69°F on May 31, and lows from 32°F to 40°F. Normal precipitation for the month is 1.93 in over about 11 wet days.
May day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
May at a glance
- Average high
- 64°F
- Average low
- 36°F
- Precipitation
- 1.93 in
- Snowfall
- 0.1 in
- Record high
- 90°FMay 19, 1954
- Record low
- 14°FMay 2, 1954
- Chance of a freeze
- 100%
- Daylight
- 14 h 18 min to 15 h 23 min
- Cloud cover
- 68%
- Humidity
- 64%
- Dew point
- 31°F
- Wind
- 6.9 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| May 1 | 59°F | 32°F | 81°F 1981 | 15°F 1954 | 31% | 0% |
| May 2 | 60°F | 32°F | 85°F 1947 | 14°F 1954 | 31% | 0% |
| May 3 | 60°F | 32°F | 84°F 1966 | 18°F 1959 | 31% | 0% |
| May 4 | 61°F | 33°F | 85°F 1966 | 22°F 1982 | 31% | 0% |
| May 5 | 61°F | 33°F | 86°F 1966 | 19°F 2010 | 32% | 0% |
| May 6 | 61°F | 33°F | 86°F 1966 | 19°F 1968 | 32% | 0% |
| May 7 | 62°F | 34°F | 84°F 1987 | 22°F 1965 | 32% | 0% |
| May 8 | 62°F | 34°F | 83°F 1947 | 20°F 2002 | 32% | 0% |
| May 9 | 62°F | 34°F | 81°F 2012 | 23°F 2002 | 33% | 0% |
| May 10 | 63°F | 35°F | 81°F 1960 | 19°F 1946 | 33% | 0% |
| May 11 | 63°F | 35°F | 83°F 1960 | 20°F 1967 | 33% | 0% |
| May 12 | 63°F | 35°F | 85°F 2026 | 22°F 1985 | 33% | 0% |
| May 13 | 64°F | 35°F | 87°F 2013 | 20°F 1943 | 33% | 0% |
| May 14 | 64°F | 36°F | 82°F 1987 | 20°F 1983 | 34% | 0% |
| May 15 | 64°F | 36°F | 84°F 1973 | 24°F 1943 | 34% | 0% |
| May 16 | 65°F | 36°F | 85°F 1973 | 20°F 1974 | 34% | 0% |
| May 17 | 65°F | 37°F | 84°F 1970 | 26°F 1960 | 34% | 0% |
| May 18 | 65°F | 37°F | 89°F 2009 | 25°F 1960 | 34% | 0% |
| May 19 | 66°F | 37°F | 90°F 1954 | 22°F 2003 | 35% | 0% |
| May 20 | 66°F | 38°F | 89°F 1958 | 24°F 2003 | 35% | 0% |
| May 21 | 66°F | 38°F | 84°F 1966 | 25°F 2001 | 35% | 0% |
| May 22 | 66°F | 38°F | 85°F 1967 | 25°F 2021 | 35% | 0% |
| May 23 | 67°F | 38°F | 87°F 1992 | 23°F 1986 | 35% | 0% |
| May 24 | 67°F | 38°F | 85°F 1988 | 27°F 1950 | 35% | 0% |
| May 25 | 67°F | 39°F | 83°F 1958 | 19°F 1950 | 36% | 0% |
| May 26 | 67°F | 39°F | 88°F 1958 | 26°F 1978 | 36% | 0% |
| May 27 | 68°F | 39°F | 88°F 1966 | 30°F 2011 | 36% | 0% |
| May 28 | 68°F | 39°F | 89°F 2003 | 25°F 1947 | 36% | 0% |
| May 29 | 68°F | 40°F | 87°F 2003 | 23°F 1982 | 36% | 0% |
| May 30 | 68°F | 40°F | 88°F 2020 | 28°F 1978 | 36% | 0% |
| May 31 | 69°F | 40°F | 87°F 1972 | 25°F 1982 | 36% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- May 1
- sunrise 6:19 AM, sunset 8:37 PM
- May 31
- sunrise 5:47 AM, sunset 9:10 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00242409 (Dillon U Of Montana Western), public domain. Records: NOAA GHCN-Daily, station USW00024138, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.