Mahaska County climate

Mahaska County Weather in September

NOAA 1991-2020 normals for Oskaloosa, 1.6 km from Mahaska County

Average highs run from 82°F on September 1 to 72°F on September 30, and lows from 58°F to 47°F. Normal precipitation for the month is 3.56 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 Mahaska County, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
77°F
Average low
53°F
Precipitation
3.56 in
Record high
100°FSep 1, 1984
Record low
27°FSep 29, 1984
Chance of a freeze
13%
Days of 90°F or more
1.5
Daylight
13 h 06 min to 11 h 48 min
Cloud cover
47%
Humidity
71%
Dew point
54°F
Wind
9.4 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 182°F58°F100°F 198442°F 194926%0%
Sep 281°F58°F99°F 200049°F 195226%0%
Sep 381°F58°F95°F 196040°F 197425%0%
Sep 481°F57°F96°F 202343°F 197425%0%
Sep 581°F57°F96°F 196042°F 196225%0%
Sep 680°F57°F97°F 198542°F 202525%0%
Sep 780°F56°F96°F 201339°F 202525%0%
Sep 880°F56°F95°F 197141°F 202425%0%
Sep 980°F56°F98°F 201340°F 200825%0%
Sep 1079°F55°F96°F 201343°F 196725%0%
Sep 1179°F55°F97°F 200043°F 195525%0%
Sep 1279°F55°F93°F 198438°F 200725%0%
Sep 1379°F54°F96°F 202536°F 201425%0%
Sep 1478°F54°F95°F 202538°F 201125%0%
Sep 1578°F53°F94°F 195532°F 200725%0%
Sep 1678°F53°F92°F 194837°F 198425%0%
Sep 1777°F53°F93°F 195339°F 198125%0%
Sep 1877°F52°F93°F 194840°F 197325%0%
Sep 1977°F52°F96°F 194834°F 199125%0%
Sep 2076°F51°F94°F 202232°F 200625%0%
Sep 2176°F51°F92°F 201636°F 199925%0%
Sep 2275°F51°F92°F 201733°F 199525%0%
Sep 2375°F50°F92°F 201730°F 201225%0%
Sep 2475°F50°F91°F 198433°F 201224%0%
Sep 2574°F49°F88°F 195635°F 200124%0%
Sep 2674°F49°F90°F 195329°F 198424%0%
Sep 2773°F49°F89°F 197138°F 198224%0%
Sep 2873°F48°F99°F 195333°F 202224%0%
Sep 2973°F48°F93°F 195327°F 198424%0%
Sep 3072°F47°F93°F 202331°F 200324%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Mahaska County, in percent, and of at least 0.1 inch of snowfall.01020301102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

September 1
sunrise 6:37 AM, sunset 7:43 PM
September 30
sunrise 7:06 AM, sunset 6:54 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00136327 (Oskaloosa), public domain. Records: NOAA GHCN-Daily, station USW00014950, 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.