September weather in Griswold, IA
The average temperature in Griswold in September is 64.8°F (52.8°F–76.7°F). Average precipitation: 3.62 inches.
September is a fall month in Griswold, and is warmer than the annual average of 49.4°F. Daily temperatures swing about 23.9°F between overnight low and afternoon high. Expect about 8 days with precipitation. Daylight averages about 12h 16m. For travel, September is one of the best months of the year to visit.
Avg High
76.7°F
Avg Low
52.8°F
Precipitation
3.62 in
Daylight
12h 16m
September records in Griswold
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 100.0°F (1922) | 33.1°F (1949) | 2.87 in (1924) |
| September 2 | 97.0°F (1937) | 42.1°F (1924) | 2.40 in (1948) |
| September 3 | 100.9°F (1939) | 32.0°F (1974) | 0.91 in (1961) |
| September 4 | 96.1°F (1954) | 37.9°F (1974) | 1.97 in (1989) |
| September 5 | 96.1°F (1922) | 35.1°F (1962) | 2.83 in (1936) |
| September 6 | 102.9°F (1939) | 39.9°F (1988) | 2.92 in (1958) |
| September 7 | 102.9°F (1939) | 36.0°F (1956) | 2.48 in (1965) |
| September 8 | 99.0°F (1955) | 41.0°F (1986) | 2.40 in (1989) |
| September 9 | 100.0°F (1955) | 36.0°F (1943) | 2.85 in (1989) |
| September 10 | 96.1°F (1933) | 32.0°F (1976) | 4.71 in (2014) |
| September 11 | 97.0°F (1936) | 33.1°F (1955) | 2.95 in (1972) |
| September 12 | 97.0°F (1939) | 32.0°F (1940) | 2.70 in (1961) |
| September 13 | 99.0°F (1939) | 33.1°F (1974) | 3.53 in (1978) |
| September 14 | 100.0°F (1939) | 34.0°F (1923) | 1.75 in (1970) |
| September 15 | 99.0°F (1939) | 33.1°F (1979) | 2.84 in (1936) |
| September 16 | 96.1°F (1931) | 32.0°F (1937) | 2.33 in (1988) |
| September 17 | 96.1°F (1925) | 30.0°F (1980) | 1.47 in (2017) |
| September 18 | 93.9°F (1947) | 28.9°F (1981) | 3.25 in (1919) |
| September 19 | 93.9°F (1931) | 30.9°F (1991) | 1.77 in (2010) |
| September 20 | 93.0°F (1935) | 30.0°F (1943) | 4.03 in (1921) |
| September 21 | 97.0°F (1937) | 30.0°F (1982) | 1.79 in (1965) |
| September 22 | 99.0°F (1937) | 28.0°F (1995) | 2.20 in (1926) |
| September 23 | 91.9°F (2017) | 23.0°F (1983) | 1.61 in (1997) |
| September 24 | 91.9°F (1935) | 27.0°F (1942) | 1.63 in (1931) |
| September 25 | 90.0°F (2017) | 30.0°F (1926) | 1.95 in (1934) |
| September 26 | 91.0°F (1998) | 27.0°F (1926) | 2.55 in (1973) |
| September 27 | 91.0°F (1956) | 27.0°F (1942) | 1.35 in (1924) |
| September 28 | 100.9°F (1953) | 21.9°F (1942) | 1.48 in (1987) |
| September 29 | 91.9°F (1981) | 24.1°F (1949) | 4.65 in (1954) |
| September 30 | 91.9°F (2023) | 25.0°F (1939) | 1.67 in (2021) |