Prosser Weather in May
Average highs run from 70°F on May 1 to 77°F on May 31, and lows from 43°F to 51°F. Normal precipitation for the month is 0.88 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
- 48°F
- Precipitation
- 0.88 in
- Record high
- 104°FMay 31, 1986
- Record low
- 24°FMay 2, 1899
- Chance of a freeze
- 20%
- Days of 90°F or more
- 2.0
- Daylight
- 14 h 23 min to 15 h 31 min
- Cloud cover
- 58%
- Humidity
- 54%
- Dew point
- 41°F
- Wind
- 9.6 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 | 70°F | 43°F | 89°F 1957 | 27°F 1913 | 18% |
| May 2 | 70°F | 44°F | 91°F 1937 | 24°F 1899 | 18% |
| May 3 | 71°F | 44°F | 90°F 1937 | 29°F 1928 | 18% |
| May 4 | 71°F | 44°F | 90°F 1966 | 29°F 1917 | 18% |
| May 5 | 71°F | 45°F | 95°F 1966 | 28°F 1924 | 18% |
| May 6 | 72°F | 45°F | 98°F 1966 | 28°F 2010 | 18% |
| May 7 | 72°F | 45°F | 96°F 1992 | 28°F 1930 | 18% |
| May 8 | 72°F | 46°F | 96°F 1987 | 29°F 1922 | 18% |
| May 9 | 73°F | 46°F | 97°F 1987 | 25°F 1922 | 18% |
| May 10 | 73°F | 46°F | 96°F 1924 | 30°F 1909 | 18% |
| May 11 | 73°F | 47°F | 97°F 1924 | 26°F 1916 | 18% |
| May 12 | 73°F | 47°F | 98°F 1931 | 31°F 1899 | 18% |
| May 13 | 74°F | 47°F | 97°F 1931 | 31°F 1916 | 18% |
| May 14 | 74°F | 48°F | 96°F 1939 | 32°F 1943 | 18% |
| May 15 | 74°F | 48°F | 97°F 1924 | 32°F 1915 | 19% |
| May 16 | 74°F | 48°F | 95°F 1924 | 30°F 1917 | 19% |
| May 17 | 75°F | 49°F | 99°F 2006 | 31°F 1896 | 19% |
| May 18 | 75°F | 49°F | 99°F 2006 | 31°F 1941 | 19% |
| May 19 | 75°F | 49°F | 97°F 1956 | 32°F 1898 | 19% |
| May 20 | 75°F | 49°F | 93°F 1928 | 30°F 1927 | 19% |
| May 21 | 76°F | 50°F | 97°F 1928 | 32°F 1918 | 19% |
| May 22 | 76°F | 50°F | 94°F 1910 | 31°F 1920 | 18% |
| May 23 | 76°F | 50°F | 96°F 1910 | 31°F 1911 | 18% |
| May 24 | 76°F | 50°F | 101°F 2001 | 31°F 1926 | 18% |
| May 25 | 76°F | 50°F | 97°F 2001 | 32°F 1918 | 18% |
| May 26 | 76°F | 51°F | 99°F 1936 | 33°F 1922 | 18% |
| May 27 | 77°F | 51°F | 99°F 1958 | 33°F 1922 | 18% |
| May 28 | 77°F | 51°F | 101°F 1934 | 33°F 1895 | 17% |
| May 29 | 77°F | 51°F | 99°F 1897 | 32°F 1920 | 17% |
| May 30 | 77°F | 51°F | 101°F 1986 | 31°F 1923 | 17% |
| May 31 | 77°F | 51°F | 104°F 1986 | 34°F 1919 | 17% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PDT).
- May 1
- sunrise 5:45 AM, sunset 8:08 PM
- May 31
- sunrise 5:12 AM, sunset 8:43 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00456768 (Prosser), public domain. Records: NOAA GHCN-Daily, station USC00458207, 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.