Union County Weather in May
Average highs run from 69°F on May 1 to 79°F on May 31, and lows from 38°F to 49°F. Normal precipitation for the month is 1.65 in over about 6 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
- 74°F
- Average low
- 44°F
- Precipitation
- 1.65 in
- Record high
- 99°FMay 27, 1896
- Record low
- 20°FMay 7, 1917
- Chance of a freeze
- 66%
- Days of 90°F or more
- 1.0
- Daylight
- 13 h 42 min to 14 h 28 min
- Cloud cover
- 48%
- Humidity
- 43%
- Dew point
- 33°F
- Wind
- 12.5 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 | 69°F | 38°F | 90°F 1992 | 22°F 1909 | 17% | |
| May 2 | 69°F | 38°F | 89°F 2012 | 23°F 1929 | 17% | |
| May 3 | 69°F | 39°F | 90°F 1940 | 24°F 1954 | 18% | |
| May 4 | 70°F | 39°F | 90°F 2012 | 26°F 1899 | 18% | |
| May 5 | 70°F | 39°F | 93°F 1934 | 27°F 1917 | 18% | |
| May 6 | 70°F | 40°F | 92°F 1916 | 27°F 1915 | 18% | |
| May 7 | 71°F | 40°F | 95°F 2022 | 20°F 1917 | 18% | |
| May 8 | 71°F | 41°F | 92°F 1934 | 29°F 1917 | 18% | |
| May 9 | 71°F | 41°F | 93°F 1916 | 32°F 1898 | 18% | |
| May 10 | 72°F | 41°F | 93°F 2000 | 27°F 1918 | 19% | |
| May 11 | 72°F | 42°F | 94°F 1962 | 30°F 1918 | 19% | |
| May 12 | 72°F | 42°F | 94°F 1962 | 30°F 1918 | 19% | |
| May 13 | 73°F | 42°F | 91°F 1941 | 28°F 1953 | 19% | |
| May 14 | 73°F | 43°F | 91°F 1963 | 29°F 1953 | 19% | |
| May 15 | 73°F | 43°F | 92°F 1974 | 32°F 1920 | 19% | |
| May 16 | 74°F | 44°F | 93°F 1927 | 29°F 1943 | 20% | |
| May 17 | 74°F | 44°F | 97°F 1927 | 34°F 1910 | 20% | |
| May 18 | 75°F | 44°F | 92°F 1956 | 33°F 1986 | 20% | |
| May 19 | 75°F | 45°F | 94°F 2006 | 29°F 1915 | 20% | |
| May 20 | 75°F | 45°F | 93°F 1925 | 29°F 1915 | 21% | |
| May 21 | 76°F | 45°F | 94°F 2005 | 30°F 1931 | 21% | |
| May 22 | 76°F | 46°F | 93°F 2012 | 33°F 1910 | 21% | |
| May 23 | 76°F | 46°F | 96°F 2000 | 36°F 1957 | 21% | |
| May 24 | 77°F | 47°F | 95°F 1984 | 37°F 1924 | 21% | 0% |
| May 25 | 77°F | 47°F | 96°F 2006 | 28°F 1924 | 21% | 0% |
| May 26 | 77°F | 47°F | 96°F 2006 | 35°F 1917 | 21% | 0% |
| May 27 | 78°F | 48°F | 99°F 1896 | 32°F 1917 | 22% | 0% |
| May 28 | 78°F | 48°F | 95°F 1934 | 34°F 1947 | 22% | 0% |
| May 29 | 78°F | 48°F | 99°F 2000 | 29°F 1947 | 22% | 0% |
| May 30 | 79°F | 49°F | 99°F 2000 | 38°F 1947 | 22% | 0% |
| May 31 | 79°F | 49°F | 98°F 2002 | 40°F 1964 | 22% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- May 1
- sunrise 6:00 AM, sunset 7:42 PM
- May 31
- sunrise 5:38 AM, sunset 8:06 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00293706 (Grenville), public domain. Records: NOAA GHCN-Daily, station USW00023051, 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.