May weather in Union, OR
The average temperature in Union in May is 54.4°F (41.4°F–67.5°F). Average precipitation: 2.47 inches.
May is a spring month in Union, and is warmer than the annual average of 49°F. Daily temperatures swing about 26.1°F between overnight low and afternoon high. Expect about 13 days with precipitation. Daylight averages about 14h 40m. For travel, May is a comfortable month to visit.
Avg High
67.5°F
Avg Low
41.4°F
Precipitation
2.47 in
Snow
0.1 in
May records in Union
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| May 1 | 82.0°F (1981) | 19.9°F (1954) | 0.61 in (1941) |
| May 2 | 84.9°F (1924) | 21.9°F (1954) | 0.39 in (1959) |
| May 3 | 86.0°F (1918) | 25.0°F (1928) | 0.77 in (2009) |
| May 4 | 87.1°F (1966) | 21.0°F (1952) | 1.15 in (1960) |
| May 5 | 90.0°F (1966) | 24.1°F (1917) | 0.86 in (2024) |
| May 6 | 91.0°F (1966) | 24.1°F (1919) | 0.79 in (2005) |
| May 7 | 87.1°F (1992) | 27.0°F (1916) | 1.33 in (1970) |
| May 8 | 89.1°F (1987) | 26.1°F (2002) | 1.90 in (1952) |
| May 9 | 86.0°F (1924) | 23.0°F (1922) | 0.87 in (1980) |
| May 10 | 89.1°F (1924) | 25.0°F (1999) | 0.60 in (1989) |
| May 11 | 88.0°F (1924) | 25.0°F (1942) | 0.86 in (1951) |
| May 12 | 90.0°F (1924) | 25.0°F (1943) | 0.44 in (1913) |
| May 13 | 88.0°F (1936) | 26.1°F (1916) | 0.57 in (1941) |
| May 14 | 87.1°F (1939) | 21.9°F (1916) | 0.57 in (1996) |
| May 15 | 88.0°F (1939) | 26.1°F (1916) | 0.60 in (2001) |
| May 16 | 91.0°F (2006) | 27.0°F (1986) | 0.92 in (2005) |
| May 17 | 91.9°F (2006) | 28.0°F (1917) | 1.20 in (2019) |
| May 18 | 93.0°F (2006) | 27.0°F (1965) | 0.68 in (1921) |
| May 19 | 89.1°F (1954) | 26.1°F (2003) | 1.42 in (1991) |
| May 20 | 87.1°F (1928) | 27.0°F (1920) | 1.10 in (2020) |
| May 21 | 87.1°F (1919) | 25.0°F (1976) | 0.95 in (1925) |
| May 22 | 88.0°F (1967) | 25.0°F (1960) | 1.33 in (1998) |
| May 23 | 89.1°F (2001) | 24.1°F (1964) | 0.39 in (2006) |
| May 24 | 95.0°F (2001) | 28.0°F (1920) | 0.73 in (1977) |
| May 25 | 91.0°F (2003) | 23.0°F (1918) | 1.09 in (1998) |
| May 26 | 91.9°F (1928) | 27.0°F (1918) | 1.02 in (2018) |
| May 27 | 91.0°F (1986) | 27.0°F (1973) | 0.89 in (1946) |
| May 28 | 91.0°F (1934) | 21.9°F (1933) | 0.68 in (1915) |
| May 29 | 91.9°F (1983) | 30.0°F (1976) | 1.31 in (1953) |
| May 30 | 93.9°F (1986) | 28.0°F (1920) | 1.47 in (1930) |
| May 31 | 93.0°F (1986) | 28.9°F (1926) | 1.03 in (1941) |