Thermopolis Weather in May
Average highs run from 66°F on May 1 to 77°F on May 31, and lows from 37°F to 47°F. Normal precipitation for the month is 2.53 in over about 8 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
- 43°F
- Precipitation
- 2.53 in
- Snowfall
- 0.2 in
- Record high
- 98°FMay 31, 1936
- Record low
- 12°FMay 2, 1954
- Chance of a freeze
- 69%
- Days of 90°F or more
- 0.8
- Daylight
- 14 h 11 min to 15 h 12 min
- Cloud cover
- 62%
- Humidity
- 52%
- Dew point
- 34°F
- Wind
- 8.1 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 | 66°F | 37°F | 88°F 1901 | 17°F 1954 | 25% | 1% |
| May 2 | 66°F | 38°F | 85°F 1952 | 12°F 1954 | 25% | 1% |
| May 3 | 67°F | 38°F | 89°F 1952 | 20°F 1903 | 25% | 1% |
| May 4 | 67°F | 38°F | 87°F 1939 | 22°F 1899 | 25% | 1% |
| May 5 | 67°F | 39°F | 89°F 1939 | 18°F 1903 | 25% | 1% |
| May 6 | 68°F | 39°F | 89°F 1934 | 16°F 1909 | 25% | 1% |
| May 7 | 68°F | 40°F | 90°F 1934 | 27°F 1924 | 25% | 1% |
| May 8 | 68°F | 40°F | 91°F 1934 | 24°F 1929 | 25% | 1% |
| May 9 | 69°F | 40°F | 87°F 1934 | 22°F 2002 | 25% | 1% |
| May 10 | 69°F | 41°F | 87°F 1900 | 21°F 1916 | 25% | 1% |
| May 11 | 70°F | 41°F | 90°F 2026 | 21°F 1916 | 25% | 1% |
| May 12 | 70°F | 41°F | 90°F 1960 | 19°F 1953 | 25% | 0% |
| May 13 | 70°F | 42°F | 95°F 2026 | 25°F 1909 | 25% | 0% |
| May 14 | 71°F | 42°F | 91°F 2001 | 26°F 1953 | 26% | 0% |
| May 15 | 71°F | 42°F | 93°F 1936 | 30°F 1916 | 26% | 0% |
| May 16 | 71°F | 43°F | 96°F 1936 | 22°F 1916 | 26% | 0% |
| May 17 | 72°F | 43°F | 91°F 1901 | 27°F 1899 | 26% | 0% |
| May 18 | 72°F | 43°F | 95°F 1901 | 22°F 1963 | 26% | 0% |
| May 19 | 73°F | 44°F | 93°F 1954 | 27°F 1950 | 26% | 0% |
| May 20 | 73°F | 44°F | 92°F 2009 | 30°F 1941 | 26% | 0% |
| May 21 | 73°F | 44°F | 91°F 1958 | 25°F 1908 | 26% | 0% |
| May 22 | 74°F | 45°F | 90°F 1932 | 27°F 1903 | 27% | 0% |
| May 23 | 74°F | 45°F | 87°F 1926 | 26°F 1916 | 27% | 0% |
| May 24 | 75°F | 45°F | 88°F 1926 | 30°F 2002 | 27% | 0% |
| May 25 | 75°F | 46°F | 90°F 2026 | 31°F 1953 | 27% | 0% |
| May 26 | 75°F | 46°F | 92°F 1934 | 33°F 1911 | 27% | 0% |
| May 27 | 76°F | 46°F | 93°F 1934 | 30°F 1916 | 27% | 0% |
| May 28 | 76°F | 46°F | 94°F 1934 | 30°F 1954 | 27% | 0% |
| May 29 | 76°F | 47°F | 96°F 2003 | 31°F 1954 | 27% | 0% |
| May 30 | 77°F | 47°F | 96°F 2003 | 31°F 1917 | 27% | 0% |
| May 31 | 77°F | 47°F | 98°F 1936 | 31°F 1954 | 27% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- May 1
- sunrise 6:05 AM, sunset 8:16 PM
- May 31
- sunrise 5:35 AM, sunset 8:47 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00488875 (Thermopolis), public domain. Records: NOAA GHCN-Daily, station USC00488875, 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.