Riverton Weather in May
Average highs run from 65°F on May 1 to 77°F on May 31, and lows from 40°F to 47°F. Normal precipitation for the month is 2.42 in over about 9 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
- 71°F
- Average low
- 44°F
- Precipitation
- 2.42 in
- Snowfall
- 0.5 in
- Record high
- 99°FMay 28, 2003
- Record low
- 25°FMay 6, 1965
- Chance of a freeze
- 57%
- Daylight
- 13 h 57 min to 14 h 52 min
- Cloud cover
- 59%
- Humidity
- 52%
- Dew point
- 36°F
- Wind
- 6.7 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 | 65°F | 40°F | 87°F 1981 | 27°F 1967 | 33% | 4% |
| May 2 | 65°F | 40°F | 88°F 1985 | 28°F 1967 | 32% | 4% |
| May 3 | 66°F | 41°F | 86°F 1966 | 28°F 1948 | 32% | 3% |
| May 4 | 66°F | 41°F | 86°F 1966 | 31°F 1964 | 32% | 3% |
| May 5 | 66°F | 41°F | 88°F 1966 | 28°F 1961 | 32% | 3% |
| May 6 | 67°F | 41°F | 88°F 1966 | 25°F 1965 | 32% | 3% |
| May 7 | 67°F | 42°F | 87°F 1989 | 27°F 1965 | 31% | 3% |
| May 8 | 67°F | 42°F | 87°F 1954 | 26°F 2002 | 31% | 2% |
| May 9 | 68°F | 42°F | 87°F 1954 | 33°F 1990 | 31% | 2% |
| May 10 | 68°F | 43°F | 92°F 1961 | 31°F 1948 | 31% | 2% |
| May 11 | 69°F | 43°F | 92°F 2026 | 30°F 1999 | 30% | 2% |
| May 12 | 69°F | 43°F | 93°F 2026 | 32°F 1967 | 30% | 2% |
| May 13 | 69°F | 43°F | 93°F 2013 | 30°F 1967 | 30% | 2% |
| May 14 | 70°F | 44°F | 89°F 2013 | 33°F 1967 | 30% | 1% |
| May 15 | 70°F | 44°F | 90°F 2012 | 32°F 1955 | 29% | 1% |
| May 16 | 71°F | 44°F | 90°F 1948 | 30°F 1955 | 29% | 1% |
| May 17 | 71°F | 44°F | 89°F 1948 | 33°F 1971 | 29% | 1% |
| May 18 | 71°F | 45°F | 92°F 2006 | 33°F 1960 | 29% | 1% |
| May 19 | 72°F | 45°F | 93°F 1958 | 31°F 1960 | 28% | 1% |
| May 20 | 72°F | 45°F | 93°F 2008 | 33°F 1959 | 28% | 1% |
| May 21 | 73°F | 45°F | 94°F 2012 | 35°F 1959 | 28% | 1% |
| May 22 | 73°F | 45°F | 89°F 1967 | 33°F 1960 | 28% | 1% |
| May 23 | 73°F | 46°F | 92°F 2003 | 30°F 1966 | 27% | 1% |
| May 24 | 74°F | 46°F | 93°F 2003 | 33°F 2010 | 27% | 1% |
| May 25 | 74°F | 46°F | 92°F 1961 | 32°F 1975 | 26% | 1% |
| May 26 | 75°F | 46°F | 94°F 2022 | 34°F 1975 | 26% | 1% |
| May 27 | 75°F | 47°F | 93°F 1951 | 37°F 1965 | 26% | 1% |
| May 28 | 75°F | 47°F | 99°F 2003 | 32°F 1954 | 25% | 0% |
| May 29 | 76°F | 47°F | 99°F 2003 | 39°F 1955 | 25% | 0% |
| May 30 | 76°F | 47°F | 98°F 2020 | 34°F 1979 | 24% | 0% |
| May 31 | 77°F | 47°F | 95°F 1997 | 36°F 1978 | 24% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- May 1
- sunrise 6:27 AM, sunset 8:24 PM
- May 31
- sunrise 6:00 AM, sunset 8:52 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00420061 (Alpine), public domain. Records: NOAA GHCN-Daily, station USW00024127, 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.