August weather in Sumner, IL
The average temperature in Sumner in August is 75.2°F (63.3°F–87.1°F). Average precipitation: 3.07 inches.
August is a summer month in Sumner, and is warmer than the annual average of 54.9°F. Daily temperatures swing about 23.8°F between overnight low and afternoon high. Expect about 7 days with precipitation. Daylight averages about 13h 31m. For travel, August is a comfortable month to visit.
Avg High
87.1°F
Avg Low
63.3°F
Precipitation
3.07 in
Daylight
13h 31m
August records in Sumner
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 100.9°F (2012) | 53.1°F (1992) | 2.13 in (1968) |
| August 2 | 96.1°F (2012) | 53.1°F (1992) | 2.28 in (2022) |
| August 3 | 100.0°F (2012) | 55.9°F (1992) | 2.06 in (2012) |
| August 4 | 100.9°F (1991) | 57.0°F (2021) | 1.98 in (1968) |
| August 5 | 99.0°F (2010) | 55.9°F (1992) | 4.37 in (2025) |
| August 6 | 99.0°F (2002) | 51.1°F (1994) | 2.26 in (1981) |
| August 7 | 99.0°F (2007) | 51.1°F (1994) | 2.25 in (2023) |
| August 8 | 100.0°F (2007) | 55.0°F (1997) | 1.42 in (1964) |
| August 9 | 102.9°F (2007) | 54.0°F (2017) | 1.30 in (2006) |
| August 10 | 99.0°F (2007) | 55.0°F (1994) | 2.45 in (2021) |
| August 11 | 98.1°F (2010) | 55.0°F (2004) | 1.50 in (2006) |
| August 12 | 97.0°F (2010) | 48.0°F (2004) | 2.55 in (1977) |
| August 13 | 100.0°F (2007) | 48.0°F (2004) | 1.50 in (1993) |
| August 14 | 98.1°F (2005) | 52.0°F (1963) | 3.24 in (2016) |
| August 15 | 93.9°F (2010) | 50.0°F (2004) | 1.98 in (1985) |
| August 16 | 100.9°F (2007) | 48.9°F (2004) | 0.75 in (1986) |
| August 17 | 98.1°F (2007) | 50.0°F (2004) | 2.09 in (2012) |
| August 18 | 93.9°F (2003) | 51.1°F (1963) | 1.72 in (1974) |
| August 19 | 91.0°F (1993) | 54.0°F (2023) | 1.98 in (2001) |
| August 20 | 93.9°F (2005) | 53.1°F (1963) | 0.74 in (1970) |
| August 21 | 93.9°F (2007) | 50.0°F (2024) | 1.04 in (2010) |
| August 22 | 95.0°F (2003) | 48.0°F (2024) | 2.65 in (2019) |
| August 23 | 99.0°F (2007) | 52.0°F (2024) | 2.05 in (2000) |
| August 24 | 100.0°F (2007) | 53.1°F (2017) | 1.94 in (1977) |
| August 25 | 100.0°F (2007) | 54.0°F (2025) | 0.66 in (2004) |
| August 26 | 97.0°F (2023) | 50.0°F (2025) | 1.65 in (2005) |
| August 27 | 96.1°F (2003) | 48.0°F (2025) | 1.75 in (1981) |
| August 28 | 95.0°F (1993) | 46.0°F (2025) | 1.46 in (1974) |
| August 29 | 99.0°F (2007) | 50.0°F (2025) | 3.07 in (1994) |
| August 30 | 95.0°F (2007) | 53.1°F (1992) | 1.65 in (1978) |
| August 31 | 98.1°F (2013) | 53.1°F (2009) | 2.62 in (2003) |