May weather in Potomac, IL
The average temperature in Potomac in May is 63.4°F (52.5°F–74.3°F). Average precipitation: 4.78 inches.
May is a spring month in Potomac, and is warmer than the annual average of 52.3°F. Daily temperatures swing about 21.8°F between overnight low and afternoon high. Expect about 11 days with precipitation. Daylight averages about 14h 14m. For travel, May is a comfortable month to visit.
Avg High
74.3°F
Avg Low
52.5°F
Precipitation
4.78 in
Daylight
14h 14m
May records in Potomac
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| May 1 | 89.1°F (1951) | 28.0°F (1903) | 2.64 in (1940) |
| May 2 | 89.1°F (1959) | 28.9°F (1966) | 2.09 in (1983) |
| May 3 | 90.0°F (1938) | 28.0°F (1978) | 1.13 in (1998) |
| May 4 | 89.1°F (1949) | 28.9°F (1926) | 1.38 in (2017) |
| May 5 | 95.0°F (1952) | 30.9°F (1911) | 1.10 in (1965) |
| May 6 | 91.0°F (1934) | 28.0°F (1968) | 2.05 in (2012) |
| May 7 | 88.0°F (1936) | 28.0°F (1989) | 1.61 in (1908) |
| May 8 | 89.1°F (2014) | 28.0°F (1928) | 1.34 in (1962) |
| May 9 | 93.9°F (1934) | 27.0°F (1947) | 2.02 in (2021) |
| May 10 | 91.9°F (1928) | 25.0°F (1966) | 1.71 in (1962) |
| May 11 | 93.9°F (2022) | 30.0°F (1907) | 3.65 in (1933) |
| May 12 | 91.9°F (1956) | 28.0°F (1938) | 2.90 in (1970) |
| May 13 | 91.0°F (1956) | 27.0°F (1938) | 2.24 in (1955) |
| May 14 | 90.0°F (1932) | 30.9°F (1910) | 1.19 in (1995) |
| May 15 | 91.0°F (1911) | 33.1°F (1920) | 1.53 in (1945) |
| May 16 | 93.9°F (2001) | 33.1°F (1984) | 2.83 in (1990) |
| May 17 | 93.0°F (1906) | 35.1°F (1932) | 2.14 in (2020) |
| May 18 | 93.0°F (1911) | 32.0°F (2002) | 2.95 in (1927) |
| May 19 | 93.9°F (1934) | 37.0°F (1929) | 1.40 in (1940) |
| May 20 | 93.9°F (1934) | 35.1°F (1906) | 1.94 in (2025) |
| May 21 | 96.1°F (1934) | 30.9°F (2002) | 1.79 in (1939) |
| May 22 | 96.1°F (1925) | 35.1°F (1924) | 1.50 in (1917) |
| May 23 | 93.0°F (1921) | 33.1°F (1963) | 1.70 in (1910) |
| May 24 | 95.0°F (1921) | 35.1°F (1935) | 2.52 in (1995) |
| May 25 | 91.9°F (1911) | 28.0°F (1925) | 1.53 in (1952) |
| May 26 | 93.9°F (1914) | 30.9°F (1925) | 2.38 in (2017) |
| May 27 | 95.0°F (1911) | 33.1°F (1961) | 2.59 in (1982) |
| May 28 | 97.0°F (2018) | 37.0°F (1907) | 1.12 in (1956) |
| May 29 | 96.1°F (1934) | 35.1°F (1965) | 5.14 in (2006) |
| May 30 | 95.0°F (1937) | 35.1°F (1947) | 2.15 in (2004) |
| May 31 | 100.9°F (1934) | 37.9°F (1930) | 1.41 in (1917) |