Waterloo climate

Waterloo Weather in August

NOAA 1991-2020 normals for Valley NWS, 7.7 km from Waterloo

Average highs run from 86°F on August 1 to 82°F on August 31, and lows from 68°F to 62°F. Normal precipitation for the month is 4.30 in over about 10 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 Waterloo, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

August at a glance

Average high
84°F
Average low
65°F
Precipitation
4.30 in
Record high
104°FAug 25, 2023
Record low
46°FAug 31, 2009
Chance of a freeze
0%
Days of 90°F or more
5.9
Daylight
14 h 21 min to 13 h 08 min
Cloud cover
50%
Humidity
67%
Dew point
61°F
Wind
8.7 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 186°F68°F101°F 200655°F 200931%0%
Aug 286°F68°F99°F 200657°F 200932%0%
Aug 386°F68°F99°F 202257°F 202132%0%
Aug 486°F68°F97°F 200852°F 201732%0%
Aug 586°F67°F98°F 202453°F 201732%0%
Aug 686°F67°F101°F 202453°F 200532%0%
Aug 785°F67°F99°F 202254°F 200532%0%
Aug 885°F67°F98°F 201259°F 201732%0%
Aug 985°F67°F95°F 200951°F 202432%0%
Aug 1085°F67°F95°F 200653°F 200432%0%
Aug 1185°F67°F95°F 201051°F 200432%0%
Aug 1285°F66°F96°F 201051°F 200432%0%
Aug 1385°F66°F95°F 201051°F 200431%0%
Aug 1485°F66°F93°F 201050°F 200431%0%
Aug 1585°F66°F93°F 200750°F 200431%0%
Aug 1684°F66°F92°F 202556°F 200431%0%
Aug 1784°F65°F93°F 202552°F 201231%0%
Aug 1884°F65°F91°F 202551°F 201231%0%
Aug 1984°F65°F94°F 200550°F 200431%0%
Aug 2084°F65°F95°F 202349°F 200430%0%
Aug 2184°F65°F94°F 201953°F 201530%0%
Aug 2284°F64°F96°F 202353°F 200930%0%
Aug 2384°F64°F97°F 202352°F 201530%0%
Aug 2483°F64°F101°F 202351°F 201530%0%
Aug 2583°F63°F104°F 202351°F 201530%0%
Aug 2683°F63°F100°F 202453°F 201529%0%
Aug 2783°F63°F98°F 202456°F 201529%0%
Aug 2883°F63°F95°F 201354°F 201929%0%
Aug 2983°F62°F95°F 201252°F 201829%0%
Aug 3082°F62°F96°F 202452°F 200929%0%
Aug 3182°F62°F97°F 201246°F 200928%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Waterloo, in percent, and of at least 0.1 inch of snowfall.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

August 1
sunrise 6:21 AM, sunset 8:42 PM
August 31
sunrise 6:51 AM, sunset 7:59 PM

Every day of August: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00258795 (Valley NWS), public domain. Records: NOAA GHCN-Daily, station USC00253467, 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.