August weather in Ottumwa, IA
The average temperature in Ottumwa in August is 73.0°F (62.0°F–84.0°F). Average precipitation: 4.44 inches.
August is a summer month in Ottumwa, and is warmer than the annual average of 50.7°F. Daily temperatures swing about 22°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 13h 39m. For travel, August is a comfortable month to visit.
Avg High
84.0°F
Avg Low
62.0°F
Precipitation
4.44 in
Daylight
13h 39m
August records in Ottumwa
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 102.0°F (1988) | 55.0°F (1973) | 0.68 in (2003) |
| August 2 | 104.0°F (2011) | 51.1°F (2009) | 1.18 in (2004) |
| August 3 | 102.0°F (1983) | 53.1°F (2020) | 2.19 in (2004) |
| August 4 | 102.9°F (1954) | 48.9°F (2020) | 2.16 in (1970) |
| August 5 | 96.1°F (2018) | 48.9°F (2020) | 3.45 in (1982) |
| August 6 | 96.1°F (2022) | 48.9°F (2004) | 1.71 in (1963) |
| August 7 | 100.0°F (1988) | 48.9°F (1989) | 1.48 in (1977) |
| August 8 | 102.0°F (1988) | 50.0°F (2017) | 1.99 in (1956) |
| August 9 | 97.0°F (2018) | 51.1°F (1972) | 2.73 in (2010) |
| August 10 | 100.0°F (1983) | 48.9°F (2024) | 0.91 in (1979) |
| August 11 | 100.0°F (1983) | 48.9°F (2012) | 2.48 in (1952) |
| August 12 | 97.0°F (1995) | 46.9°F (2004) | 1.29 in (2012) |
| August 13 | 97.0°F (1965) | 48.0°F (1964) | 2.35 in (1974) |
| August 14 | 99.0°F (1988) | 46.9°F (2013) | 1.19 in (1952) |
| August 15 | 104.0°F (1988) | 45.0°F (2004) | 1.09 in (1951) |
| August 16 | 102.9°F (1983) | 48.9°F (2013) | 2.22 in (2009) |
| August 17 | 104.0°F (1983) | 48.9°F (2012) | 1.32 in (1954) |
| August 18 | 105.1°F (1983) | 46.9°F (2012) | 1.88 in (2004) |
| August 19 | 100.9°F (1983) | 48.0°F (1950) | 1.38 in (1949) |
| August 20 | 100.9°F (1983) | 41.0°F (1950) | 4.54 in (2010) |
| August 21 | 99.0°F (1983) | 48.0°F (1950) | 1.55 in (1955) |
| August 22 | 97.0°F (1968) | 50.0°F (2024) | 2.61 in (2002) |
| August 23 | 102.0°F (1948) | 46.0°F (1984) | 3.24 in (2007) |
| August 24 | 102.9°F (2023) | 48.0°F (1984) | 1.67 in (2018) |
| August 25 | 100.9°F (2003) | 46.9°F (1958) | 3.21 in (1987) |
| August 26 | 102.0°F (1983) | 44.1°F (2025) | 2.32 in (1954) |
| August 27 | 97.0°F (1955) | 46.9°F (1986) | 2.56 in (1998) |
| August 28 | 98.1°F (1984) | 42.1°F (1986) | 4.07 in (2018) |
| August 29 | 98.1°F (1984) | 48.9°F (1965) | 2.71 in (1975) |
| August 30 | 100.9°F (2013) | 46.9°F (2009) | 2.49 in (1965) |
| August 31 | 98.1°F (1953) | 43.0°F (1967) | 1.77 in (1989) |