McLean County climate

McLean County Weather in August

NOAA 1991-2020 normals for Calhoun Lock 2, 0.4 km from McLean County

Average highs run from 87°F on August 1 to 86°F on August 31, and lows from 68°F to 64°F. Normal precipitation for the month is 2.89 in over about 6 wet days.

August day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at McLean County, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

August at a glance

Average high
87°F
Average low
67°F
Precipitation
2.89 in
Record high
105°FAug 16, 2007
Record low
45°FAug 13, 1964
Chance of a freeze
0%
Days of 90°F or more
10.5
Daylight
14 h 04 min to 13 h 00 min
Cloud cover
48%
Humidity
70%
Dew point
66°F
Wind
5.6 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
Aug 187°F68°F99°F 199949°F 197123%0%
Aug 287°F68°F100°F 198754°F 197723%0%
Aug 387°F68°F102°F 199150°F 196523%0%
Aug 487°F68°F102°F 200252°F 196623%0%
Aug 587°F68°F99°F 200253°F 195123%0%
Aug 687°F68°F98°F 196350°F 195722%0%
Aug 787°F68°F99°F 200752°F 200422%0%
Aug 887°F68°F103°F 200750°F 198922%0%
Aug 987°F67°F103°F 200749°F 197622%0%
Aug 1087°F67°F99°F 201051°F 197222%0%
Aug 1187°F67°F101°F 200553°F 196221%0%
Aug 1287°F67°F102°F 200550°F 196721%0%
Aug 1387°F67°F101°F 200545°F 196421%0%
Aug 1487°F67°F99°F 200546°F 200421%0%
Aug 1587°F67°F104°F 200747°F 200421%0%
Aug 1687°F67°F105°F 200747°F 200421%0%
Aug 1787°F67°F99°F 198850°F 200420%0%
Aug 1887°F67°F100°F 195650°F 197620%0%
Aug 1987°F67°F99°F 198355°F 195820%0%
Aug 2087°F66°F102°F 198352°F 195320%0%
Aug 2186°F66°F101°F 198348°F 195020%0%
Aug 2286°F66°F102°F 198348°F 195620%0%
Aug 2386°F66°F104°F 200750°F 195019%0%
Aug 2486°F66°F103°F 200750°F 195119%0%
Aug 2586°F65°F102°F 200750°F 195219%0%
Aug 2686°F65°F100°F 198349°F 195819%0%
Aug 2786°F65°F100°F 195449°F 196819%0%
Aug 2886°F65°F99°F 200747°F 196819%0%
Aug 2986°F65°F100°F 202447°F 196519%0%
Aug 3086°F64°F99°F 195149°F 198619%0%
Aug 3186°F64°F100°F 195351°F 197619%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at McLean 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 (CDT).

August 1
sunrise 5:53 AM, sunset 7:57 PM
August 31
sunrise 6:19 AM, sunset 7:19 PM

Every day of August: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00151227 (Calhoun Lock 2), public domain. Records: NOAA GHCN-Daily, station USC00155067, 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.