Mattoon climate

Mattoon Weather in September

NOAA 1991-2020 normals for Mattoon, 2 km from Mattoon

Average highs run from 83°F on September 1 to 74°F on September 30, and lows from 62°F to 52°F. Normal precipitation for the month is 3.11 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 Mattoon, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
79°F
Average low
57°F
Precipitation
3.11 in
Record high
99°FSep 1, 2011
Record low
34°FSep 25, 2001
Chance of a freeze
1%
Days of 90°F or more
2.5
Daylight
13 h 02 min to 11 h 48 min
Cloud cover
46%
Humidity
69%
Dew point
56°F
Wind
8.3 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 183°F62°F99°F 201141°F 200723%0%
Sep 283°F62°F98°F 201142°F 201723%0%
Sep 383°F61°F96°F 201149°F 202423%0%
Sep 482°F61°F97°F 202650°F 202423%0%
Sep 582°F60°F97°F 202648°F 200323%0%
Sep 682°F60°F94°F 199845°F 201123%0%
Sep 782°F60°F93°F 201545°F 202523%0%
Sep 882°F59°F94°F 200242°F 202424%0%
Sep 981°F59°F95°F 201344°F 202424%0%
Sep 1081°F59°F96°F 201346°F 201724%0%
Sep 1181°F58°F95°F 201344°F 201724%0%
Sep 1281°F58°F92°F 199845°F 200724%0%
Sep 1380°F57°F93°F 202540°F 201424%0%
Sep 1480°F57°F96°F 202540°F 201424%0%
Sep 1580°F57°F97°F 202636°F 200724%0%
Sep 1679°F56°F94°F 202642°F 199924%0%
Sep 1779°F56°F96°F 202644°F 199924%0%
Sep 1879°F56°F92°F 201843°F 202024%0%
Sep 1978°F55°F92°F 200539°F 202024%0%
Sep 2078°F55°F93°F 201739°F 200624%0%
Sep 2178°F55°F95°F 201740°F 199925%0%
Sep 2277°F54°F94°F 201739°F 199925%0%
Sep 2377°F54°F93°F 201740°F 201225%0%
Sep 2477°F54°F92°F 201736°F 201225%0%
Sep 2576°F53°F91°F 201734°F 200125%0%
Sep 2676°F53°F91°F 201738°F 200025%0%
Sep 2775°F53°F92°F 199842°F 201025%0%
Sep 2875°F52°F89°F 202537°F 202225%0%
Sep 2975°F52°F91°F 202538°F 202225%0%
Sep 3074°F52°F90°F 201939°F 200526%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Mattoon, 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 6:22 AM, sunset 7:24 PM
September 30
sunrise 6:49 AM, sunset 6:37 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00115430 (Mattoon), public domain. Records: NOAA GHCN-Daily, station USW00053802, 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.