Johnson County Weather in September
Average highs run from 80°F on September 1 to 73°F on September 30, and lows from 57°F to 47°F. Normal precipitation for the month is 3.26 in over about 8 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
- 77°F
- Average low
- 53°F
- Precipitation
- 3.26 in
- Record high
- 98°FSep 3, 1898
- Record low
- 31°FSep 30, 1899
- Chance of a freeze
- 6%
- Daylight
- 12 h 56 min to 11 h 50 min
- Cloud cover
- 56%
- Humidity
- 73%
- Dew point
- 54°F
- Wind
- 4.3 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 | 57°F | 95°F 2024 | 48°F 1999 | 28% | 0% |
| Sep 2 | 80°F | 57°F | 95°F 1896 | 49°F 1987 | 28% | 0% |
| Sep 3 | 80°F | 56°F | 98°F 1898 | 48°F 1908 | 28% | 0% |
| Sep 4 | 80°F | 56°F | 96°F 1899 | 44°F 1997 | 27% | 0% |
| Sep 5 | 80°F | 56°F | 96°F 1899 | 43°F 1997 | 27% | 0% |
| Sep 6 | 79°F | 56°F | 97°F 1899 | 43°F 1997 | 27% | 0% |
| Sep 7 | 79°F | 55°F | 98°F 1899 | 44°F 1988 | 27% | 0% |
| Sep 8 | 79°F | 55°F | 98°F 1899 | 43°F 1998 | 27% | 0% |
| Sep 9 | 79°F | 55°F | 96°F 1897 | 43°F 1998 | 27% | 0% |
| Sep 10 | 79°F | 55°F | 98°F 1897 | 42°F 1943 | 26% | 0% |
| Sep 11 | 78°F | 54°F | 96°F 1897 | 41°F 1943 | 26% | 0% |
| Sep 12 | 78°F | 54°F | 95°F 1897 | 46°F 1940 | 26% | 0% |
| Sep 13 | 78°F | 54°F | 96°F 1998 | 39°F 1940 | 26% | 0% |
| Sep 14 | 78°F | 53°F | 97°F 1998 | 35°F 1902 | 26% | 0% |
| Sep 15 | 77°F | 53°F | 96°F 1895 | 40°F 1985 | 26% | 0% |
| Sep 16 | 77°F | 53°F | 97°F 1897 | 40°F 2000 | 26% | 0% |
| Sep 17 | 77°F | 52°F | 97°F 1903 | 40°F 2000 | 26% | 0% |
| Sep 18 | 76°F | 52°F | 95°F 1896 | 40°F 1943 | 26% | 0% |
| Sep 19 | 76°F | 52°F | 94°F 1895 | 34°F 1901 | 26% | 0% |
| Sep 20 | 76°F | 51°F | 97°F 1895 | 39°F 1901 | 25% | 0% |
| Sep 21 | 76°F | 51°F | 97°F 1895 | 37°F 1901 | 25% | 0% |
| Sep 22 | 75°F | 50°F | 97°F 1895 | 38°F 1899 | 25% | 0% |
| Sep 23 | 75°F | 50°F | 95°F 1895 | 39°F 1983 | 25% | 0% |
| Sep 24 | 75°F | 50°F | 97°F 1895 | 34°F 1983 | 25% | 0% |
| Sep 25 | 74°F | 49°F | 97°F 1895 | 37°F 2001 | 25% | 0% |
| Sep 26 | 74°F | 49°F | 93°F 1895 | 37°F 2001 | 25% | 0% |
| Sep 27 | 74°F | 49°F | 87°F 1897 | 37°F 1993 | 25% | 0% |
| Sep 28 | 74°F | 48°F | 90°F 1898 | 36°F 1909 | 25% | 0% |
| Sep 29 | 73°F | 48°F | 89°F 2019 | 33°F 1942 | 25% | 0% |
| Sep 30 | 73°F | 47°F | 92°F 2019 | 31°F 1899 | 25% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (EDT).
- September 1
- sunrise 6:59 AM, sunset 7:55 PM
- September 30
- sunrise 7:22 AM, sunset 7:12 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00406292 (Mtn City 2), public domain. Records: NOAA GHCN-Daily, station USC00402806, 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.