Rock County Weather in September
Average highs run from 80°F on September 1 to 69°F on September 30, and lows from 55°F to 42°F. Normal precipitation for the month is 2.75 in over about 7 wet days.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 75°F
- Average low
- 49°F
- Precipitation
- 2.75 in
- Record high
- 107°FSep 9, 1931
- Record low
- 21°FSep 29, 1945
- Chance of a freeze
- 45%
- Days of 90°F or more
- 3.5
- Daylight
- 13 h 09 min to 11 h 47 min
- Cloud cover
- 47%
- Humidity
- 57%
- Dew point
- 47°F
- Wind
- 11.6 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Sep 1 | 80°F | 55°F | 100°F 1912 | 37°F 1965 | 26% | 0% |
| Sep 2 | 80°F | 54°F | 104°F 2023 | 39°F 1914 | 25% | 0% |
| Sep 3 | 79°F | 54°F | 103°F 1960 | 37°F 1934 | 25% | 0% |
| Sep 4 | 79°F | 54°F | 102°F 1931 | 38°F 1935 | 25% | 0% |
| Sep 5 | 79°F | 53°F | 100°F 1913 | 32°F 1935 | 25% | 0% |
| Sep 6 | 79°F | 53°F | 105°F 1931 | 32°F 1929 | 25% | 0% |
| Sep 7 | 78°F | 53°F | 102°F 1931 | 34°F 1929 | 25% | 0% |
| Sep 8 | 78°F | 52°F | 105°F 2022 | 37°F 1929 | 25% | 0% |
| Sep 9 | 78°F | 52°F | 107°F 1931 | 34°F 1943 | 25% | 0% |
| Sep 10 | 77°F | 51°F | 102°F 1931 | 35°F 1922 | 25% | 0% |
| Sep 11 | 77°F | 51°F | 100°F 1908 | 28°F 1940 | 25% | 0% |
| Sep 12 | 77°F | 51°F | 100°F 1908 | 33°F 1975 | 25% | 0% |
| Sep 13 | 76°F | 50°F | 99°F 1939 | 30°F 1949 | 25% | 0% |
| Sep 14 | 76°F | 50°F | 98°F 1939 | 33°F 1993 | 25% | 0% |
| Sep 15 | 75°F | 49°F | 100°F 1955 | 27°F 1916 | 25% | |
| Sep 16 | 75°F | 49°F | 97°F 1910 | 33°F 1918 | 25% | |
| Sep 17 | 75°F | 49°F | 98°F 1910 | 28°F 1918 | 25% | |
| Sep 18 | 74°F | 48°F | 99°F 1940 | 29°F 1918 | 25% | |
| Sep 19 | 74°F | 48°F | 97°F 1908 | 23°F 1918 | 25% | |
| Sep 20 | 73°F | 47°F | 97°F 1937 | 27°F 1927 | 25% | |
| Sep 21 | 73°F | 47°F | 96°F 1936 | 30°F 1913 | 25% | |
| Sep 22 | 72°F | 46°F | 95°F 1908 | 26°F 1995 | 25% | |
| Sep 23 | 72°F | 46°F | 96°F 1937 | 26°F 1989 | 25% | |
| Sep 24 | 72°F | 45°F | 93°F 1956 | 25°F 1942 | 25% | |
| Sep 25 | 71°F | 45°F | 93°F 1956 | 24°F 1912 | 24% | |
| Sep 26 | 71°F | 44°F | 97°F 1956 | 25°F 1942 | 24% | |
| Sep 27 | 70°F | 44°F | 97°F 1956 | 24°F 1924 | 24% | |
| Sep 28 | 70°F | 43°F | 95°F 2024 | 24°F 1951 | 24% | |
| Sep 29 | 69°F | 43°F | 94°F 1910 | 21°F 1945 | 24% | |
| Sep 30 | 69°F | 42°F | 96°F 1942 | 26°F 1974 | 24% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CDT).
- September 1
- sunrise 7:03 AM, sunset 8:12 PM
- September 30
- sunrise 7:34 AM, sunset 7:21 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00255925 (Newport), public domain. Records: NOAA GHCN-Daily, station USC00250050, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.