Chester climate

Chester Weather in September

NOAA 1991-2020 normals for Kaskaskia Rvr Navigation Lock, 13.4 km from Chester

Average highs run from 86°F on September 1 to 77°F on September 30, and lows from 63°F to 52°F. Normal precipitation for the month is 2.94 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 Chester, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
81°F
Average low
58°F
Precipitation
2.94 in
Record high
112°FSep 6, 1990
Record low
32°FSep 24, 1989
Chance of a freeze
0%
Days of 90°F or more
7.4
Daylight
13 h 00 min to 11 h 50 min
Cloud cover
46%
Humidity
67%
Dew point
57°F
Wind
6.3 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 186°F63°F101°F 201146°F 198621%0%
Sep 285°F62°F102°F 201150°F 201721%0%
Sep 385°F62°F100°F 201147°F 197421%0%
Sep 485°F62°F101°F 199043°F 197421%0%
Sep 585°F61°F102°F 199044°F 197422%0%
Sep 684°F61°F112°F 199043°F 198822%0%
Sep 784°F61°F112°F 199044°F 201722%0%
Sep 884°F61°F99°F 198041°F 198622%0%
Sep 984°F60°F95°F 198043°F 202422%0%
Sep 1083°F60°F105°F 198543°F 202422%0%
Sep 1183°F60°F98°F 201345°F 197622%0%
Sep 1283°F59°F98°F 199645°F 197722%0%
Sep 1382°F59°F99°F 199144°F 197522%0%
Sep 1482°F58°F98°F 199141°F 201422%0%
Sep 1582°F58°F97°F 202542°F 201422%0%
Sep 1682°F58°F99°F 202642°F 200722%0%
Sep 1781°F57°F98°F 202642°F 197922%0%
Sep 1881°F57°F98°F 202642°F 198122%0%
Sep 1981°F57°F94°F 202541°F 199122%0%
Sep 2080°F56°F94°F 197841°F 199122%0%
Sep 2180°F56°F96°F 201838°F 198322%0%
Sep 2280°F55°F95°F 201036°F 198322%0%
Sep 2379°F55°F94°F 200533°F 197422%0%
Sep 2479°F55°F93°F 201632°F 198922%0%
Sep 2578°F54°F96°F 198732°F 198922%0%
Sep 2678°F54°F93°F 201635°F 198922%0%
Sep 2778°F53°F93°F 198637°F 198522%0%
Sep 2877°F53°F93°F 198637°F 198422%0%
Sep 2977°F53°F93°F 199038°F 198422%0%
Sep 3077°F52°F92°F 199832°F 198422%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Chester, 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 6:29 AM, sunset 7:29 PM
September 30
sunrise 6:54 AM, sunset 6:44 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00114629 (Kaskaskia Rvr Navigation Lock), public domain. Records: NOAA GHCN-Daily, station USC00114629, 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.