Johnson County climate

Johnson County Weather in September

NOAA 1991-2020 normals for Billy Creek, 15.1 km from Johnson County

Average highs run from 80°F on September 1 to 67°F on September 30, and lows from 49°F to 37°F. Normal precipitation for the month is 1.29 in over about 6 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.020406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
74°F
Average low
43°F
Precipitation
1.29 in
Snowfall
0.2 in
Record high
100°FSep 4, 2022
Record low
19°FSep 12, 2014
Chance of a freeze
82%
Days of 90°F or more
2.4
Daylight
13 h 12 min to 11 h 46 min
Cloud cover
49%
Humidity
44%
Dew point
36°F
Wind
8.9 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 180°F49°F94°F 202239°F 200819%0%
Sep 280°F48°F95°F 201536°F 200819%0%
Sep 380°F48°F96°F 202241°F 200619%0%
Sep 479°F48°F100°F 202240°F 199919%0%
Sep 579°F47°F99°F 202038°F 200819%0%
Sep 679°F47°F92°F 201339°F 202519%0%
Sep 778°F47°F99°F 202233°F 202020%0%
Sep 878°F46°F93°F 199830°F 202020%1%
Sep 978°F46°F92°F 199827°F 202020%1%
Sep 1077°F45°F98°F 202132°F 201420%1%
Sep 1177°F45°F89°F 201721°F 201420%1%
Sep 1276°F45°F91°F 200419°F 201420%1%
Sep 1376°F44°F91°F 200633°F 199921%1%
Sep 1475°F44°F91°F 202033°F 200721%1%
Sep 1575°F44°F94°F 201836°F 200421%1%
Sep 1674°F43°F92°F 200036°F 200621%1%
Sep 1774°F43°F88°F 201332°F 200321%2%
Sep 1873°F42°F90°F 202128°F 200322%2%
Sep 1973°F42°F94°F 201037°F 201722%2%
Sep 2072°F41°F84°F 200534°F 200022%2%
Sep 2172°F41°F85°F 201331°F 200022%2%
Sep 2271°F41°F88°F 200725°F 200022%2%
Sep 2371°F40°F86°F 201125°F 200022%2%
Sep 2470°F40°F91°F 202027°F 200022%3%
Sep 2570°F39°F98°F 202433°F 200022%3%
Sep 2669°F39°F94°F 201529°F 199922%3%
Sep 2769°F38°F90°F 202429°F 199922%3%
Sep 2868°F38°F91°F 200128°F 199922%3%
Sep 2968°F38°F94°F 202429°F 199922%3%
Sep 3067°F37°F85°F 201132°F 200322%3%

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 (MDT).

September 1
sunrise 6:30 AM, sunset 7:42 PM
September 30
sunrise 7:03 AM, sunset 6:49 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00480740 (Billy Creek), public domain. Records: NOAA GHCN-Daily, station USW00094054, 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.