De Kalb climate

De Kalb Weather in September

NOAA 1991-2020 normals for Dekalb, 3.3 km from De Kalb

Average highs run from 92°F on September 1 to 83°F on September 30, and lows from 66°F to 57°F. Normal precipitation for the month is 4.14 in over about 5 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 De Kalb, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
88°F
Average low
63°F
Precipitation
4.14 in
Record high
109°FSep 2, 2000
Record low
36°FSep 22, 1983
Chance of a freeze
0%
Days of 90°F or more
14.8
Daylight
12 h 51 min to 11 h 52 min
Cloud cover
44%
Humidity
64%
Dew point
62°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 192°F66°F108°F 195155°F 196717%0%
Sep 292°F66°F109°F 200052°F 196717%0%
Sep 391°F66°F106°F 193950°F 195217%0%
Sep 491°F66°F107°F 193949°F 197417%0%
Sep 591°F66°F109°F 199849°F 199717%0%
Sep 691°F65°F104°F 194745°F 201117%0%
Sep 790°F65°F103°F 202343°F 201117%0%
Sep 890°F65°F104°F 202345°F 201117%0%
Sep 990°F65°F106°F 199844°F 201117%0%
Sep 1090°F64°F101°F 193646°F 202417%0%
Sep 1189°F64°F100°F 191147°F 194817%0%
Sep 1289°F64°F102°F 191140°F 194017%0%
Sep 1389°F64°F103°F 191143°F 194017%0%
Sep 1489°F63°F101°F 198045°F 194017%0%
Sep 1588°F63°F104°F 198046°F 199317%0%
Sep 1688°F63°F103°F 198045°F 200817%0%
Sep 1788°F62°F103°F 191145°F 200817%0%
Sep 1887°F62°F103°F 191144°F 198116%0%
Sep 1987°F62°F101°F 195640°F 197116%0%
Sep 2087°F61°F99°F 195443°F 193816%0%
Sep 2186°F61°F102°F 194439°F 198316%0%
Sep 2286°F61°F99°F 193136°F 198316%0%
Sep 2386°F60°F100°F 194837°F 198316%0%
Sep 2486°F60°F99°F 190741°F 198915%0%
Sep 2585°F60°F99°F 195444°F 195215%0%
Sep 2685°F59°F99°F 193941°F 194015%0%
Sep 2785°F59°F99°F 193936°F 194215%0%
Sep 2884°F58°F98°F 193840°F 194215%0%
Sep 2984°F58°F99°F 193839°F 194215%0%
Sep 3083°F57°F102°F 195339°F 199215%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at De Kalb, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

September 1
sunrise 6:53 AM, sunset 7:44 PM
September 30
sunrise 7:12 AM, sunset 7:04 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00412352 (Dekalb), public domain. Records: NOAA GHCN-Daily, station USC00344451, 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.