Johnson County climate

Johnson County Weather in September

NOAA 1991-2020 normals for Tecumseh 1S, 7.4 km from Johnson County

Average highs run from 84°F on September 1 to 74°F on September 30, and lows from 58°F to 46°F. Normal precipitation for the month is 2.74 in over about 7 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Johnson County, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
79°F
Average low
53°F
Precipitation
2.74 in
Record high
102°FSep 2, 1975
Record low
28°FSep 29, 1984
Chance of a freeze
20%
Days of 90°F or more
4.4
Daylight
13 h 04 min to 11 h 48 min
Cloud cover
46%
Humidity
66%
Dew point
54°F
Wind
10.3 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.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 184°F58°F99°F 200043°F 196725%0%
Sep 283°F58°F102°F 197543°F 196724%0%
Sep 383°F58°F102°F 200038°F 197424%0%
Sep 483°F57°F101°F 201233°F 197424%0%
Sep 583°F57°F96°F 202640°F 197424%0%
Sep 682°F57°F97°F 202644°F 196224%0%
Sep 782°F56°F99°F 198045°F 201724%0%
Sep 882°F56°F99°F 197143°F 198624%0%
Sep 982°F55°F99°F 202640°F 200824%0%
Sep 1081°F55°F97°F 198340°F 197624%0%
Sep 1181°F55°F99°F 201238°F 197624%0%
Sep 1281°F54°F95°F 200040°F 197524%0%
Sep 1380°F54°F95°F 198036°F 201424%0%
Sep 1480°F53°F94°F 202537°F 201424%0%
Sep 1580°F53°F95°F 201736°F 199324%0%
Sep 1679°F52°F91°F 201735°F 198424%0%
Sep 1779°F52°F92°F 197238°F 198024%0%
Sep 1879°F52°F92°F 198336°F 197324%0%
Sep 1978°F51°F95°F 197232°F 199124%0%
Sep 2078°F51°F95°F 202233°F 199124%0%
Sep 2178°F50°F100°F 202236°F 197124%0%
Sep 2277°F50°F98°F 200531°F 199524%0%
Sep 2377°F49°F94°F 201731°F 199524%0%
Sep 2477°F49°F92°F 201732°F 196524%0%
Sep 2576°F48°F90°F 200533°F 196524%0%
Sep 2676°F48°F91°F 199833°F 198423%0%
Sep 2776°F48°F95°F 202033°F 198423%0%
Sep 2875°F47°F93°F 197133°F 196123%0%
Sep 2975°F47°F92°F 202128°F 198423%0%
Sep 3074°F46°F93°F 202328°F 198423%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Johnson County, in percent, and of at least 0.1 inch of snowfall.05101520251102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

September 1
sunrise 6:53 AM, sunset 7:57 PM
September 30
sunrise 7:21 AM, sunset 7:09 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00258465 (Tecumseh 1S), public domain. Records: NOAA GHCN-Daily, station USC00255810, 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.