Custer County Weather in May
Average highs run from 62°F on May 1 to 71°F on May 31, and lows from 35°F to 44°F. Normal precipitation for the month is 0.93 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
- 67°F
- Average low
- 40°F
- Precipitation
- 0.93 in
- Record high
- 96°FMay 28, 2003
- Record low
- 20°FMay 8, 2002
- Chance of a freeze
- 92%
- Daylight
- 14 h 13 min to 15 h 16 min
- Cloud cover
- 66%
- Humidity
- 66%
- Dew point
- 28°F
- Wind
- 5.6 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| May 1 | 62°F | 35°F | 82°F 2023 | 20°F 2013 | 24% |
| May 2 | 62°F | 36°F | 80°F 2004 | 20°F 2008 | 24% |
| May 3 | 63°F | 36°F | 81°F 2025 | 25°F 2001 | 25% |
| May 4 | 63°F | 36°F | 81°F 2017 | 24°F 2007 | 25% |
| May 5 | 64°F | 37°F | 82°F 2017 | 24°F 1999 | 25% |
| May 6 | 64°F | 37°F | 82°F 2018 | 25°F 2003 | 26% |
| May 7 | 64°F | 37°F | 77°F 2004 | 22°F 2010 | 26% |
| May 8 | 65°F | 38°F | 82°F 2018 | 20°F 2002 | 26% |
| May 9 | 65°F | 38°F | 82°F 2025 | 22°F 2002 | 26% |
| May 10 | 65°F | 38°F | 86°F 2025 | 24°F 2008 | 27% |
| May 11 | 66°F | 39°F | 83°F 2026 | 22°F 1999 | 27% |
| May 12 | 66°F | 39°F | 87°F 2001 | 29°F 2000 | 27% |
| May 13 | 66°F | 39°F | 85°F 2013 | 23°F 2009 | 28% |
| May 14 | 67°F | 40°F | 83°F 2012 | 27°F 2017 | 28% |
| May 15 | 67°F | 40°F | 84°F 2006 | 30°F 2004 | 28% |
| May 16 | 67°F | 40°F | 86°F 2006 | 31°F 2017 | 28% |
| May 17 | 67°F | 41°F | 88°F 2008 | 26°F 2026 | 29% |
| May 18 | 68°F | 41°F | 89°F 2009 | 28°F 2003 | 29% |
| May 19 | 68°F | 41°F | 84°F 2002 | 21°F 2003 | 29% |
| May 20 | 68°F | 42°F | 87°F 2008 | 28°F 2003 | 29% |
| May 21 | 68°F | 42°F | 83°F 2023 | 27°F 2010 | 29% |
| May 22 | 69°F | 42°F | 82°F 2003 | 31°F 2010 | 29% |
| May 23 | 69°F | 42°F | 86°F 2003 | 28°F 2007 | 30% |
| May 24 | 69°F | 43°F | 87°F 2001 | 31°F 2016 | 30% |
| May 25 | 69°F | 43°F | 87°F 2001 | 32°F 2005 | 30% |
| May 26 | 70°F | 43°F | 82°F 2025 | 34°F 2011 | 30% |
| May 27 | 70°F | 43°F | 85°F 2003 | 31°F 2011 | 30% |
| May 28 | 70°F | 43°F | 96°F 2003 | 33°F 2011 | 30% |
| May 29 | 70°F | 44°F | 92°F 2003 | 31°F 2007 | 30% |
| May 30 | 70°F | 44°F | 91°F 2020 | 31°F 2006 | 29% |
| May 31 | 71°F | 44°F | 93°F 2025 | 34°F 2011 | 29% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (MDT).
- May 1
- sunrise 6:28 AM, sunset 8:41 PM
- May 31
- sunrise 5:57 AM, sunset 9:13 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00004114 (Challis AP), public domain. Records: NOAA GHCN-Daily, station USW00004114, 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.