Waterloo Weather in August
Average highs run from 92°F on August 1 to 91°F on August 31, and lows from 59°F to 58°F. Normal precipitation for the month is 0.03 in over about 1 wet days.
August day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
August at a glance
- Average high
- 92°F
- Average low
- 58°F
- Precipitation
- 0.03 in
- Record high
- 113°FAug 16, 2020
- Record low
- 47°FAug 26, 1955
- Chance of a freeze
- 0%
- Days of 90°F or more
- 19.7
- Daylight
- 14 h 06 min to 13 h 01 min
- Cloud cover
- 15%
- Humidity
- 46%
- Dew point
- 48°F
- Wind
- 8.3 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| Aug 1 | 92°F | 59°F | 109°F 1980 | 53°F 1970 | 1% |
| Aug 2 | 92°F | 59°F | 105°F 1993 | 53°F 2013 | 1% |
| Aug 3 | 92°F | 59°F | 108°F 1998 | 52°F 1963 | 1% |
| Aug 4 | 92°F | 59°F | 109°F 1998 | 51°F 2002 | 1% |
| Aug 5 | 92°F | 59°F | 108°F 1978 | 50°F 1950 | 1% |
| Aug 6 | 92°F | 59°F | 109°F 1978 | 53°F 1950 | 1% |
| Aug 7 | 92°F | 59°F | 109°F 1983 | 53°F 1950 | 1% |
| Aug 8 | 92°F | 59°F | 109°F 1978 | 52°F 1950 | 1% |
| Aug 9 | 92°F | 59°F | 108°F 1978 | 52°F 1950 | 1% |
| Aug 10 | 92°F | 58°F | 109°F 1971 | 52°F 1949 | 1% |
| Aug 11 | 92°F | 58°F | 106°F 1996 | 52°F 1950 | 1% |
| Aug 12 | 92°F | 58°F | 107°F 1996 | 50°F 1954 | 1% |
| Aug 13 | 92°F | 58°F | 108°F 1996 | 52°F 1988 | 1% |
| Aug 14 | 92°F | 58°F | 108°F 2020 | 52°F 1955 | 1% |
| Aug 15 | 92°F | 58°F | 109°F 2020 | 50°F 1999 | 1% |
| Aug 16 | 92°F | 58°F | 113°F 2020 | 50°F 1955 | 1% |
| Aug 17 | 92°F | 58°F | 109°F 2020 | 50°F 2006 | 2% |
| Aug 18 | 92°F | 58°F | 108°F 2020 | 51°F 1959 | 2% |
| Aug 19 | 92°F | 58°F | 107°F 1950 | 48°F 1959 | 2% |
| Aug 20 | 92°F | 58°F | 105°F 2022 | 50°F 1968 | 2% |
| Aug 21 | 92°F | 58°F | 104°F 2025 | 52°F 1959 | 2% |
| Aug 22 | 92°F | 58°F | 104°F 1982 | 50°F 1968 | 2% |
| Aug 23 | 92°F | 58°F | 103°F 2025 | 50°F 2002 | 2% |
| Aug 24 | 92°F | 58°F | 103°F 2010 | 50°F 2002 | 2% |
| Aug 25 | 92°F | 58°F | 108°F 2010 | 50°F 2002 | 2% |
| Aug 26 | 92°F | 58°F | 104°F 1988 | 47°F 1955 | 2% |
| Aug 27 | 91°F | 58°F | 104°F 1981 | 50°F 1952 | 2% |
| Aug 28 | 91°F | 58°F | 112°F 2017 | 49°F 1955 | 2% |
| Aug 29 | 91°F | 58°F | 108°F 2007 | 48°F 1957 | 2% |
| Aug 30 | 91°F | 58°F | 105°F 1968 | 48°F 1957 | 2% |
| Aug 31 | 91°F | 58°F | 105°F 2025 | 48°F 1957 | 2% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PDT).
- August 1
- sunrise 6:08 AM, sunset 8:14 PM
- August 31
- sunrise 6:34 AM, sunset 7:35 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00045032 (Lodi), public domain. Records: NOAA GHCN-Daily, station USW00023237, 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.