Boulder Weather in August
Average highs run from 88°F on August 1 to 84°F on August 31, and lows from 58°F to 53°F. Normal precipitation for the month is 1.68 in over about 11 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
- 86°F
- Average low
- 56°F
- Precipitation
- 1.68 in
- Record high
- 104°FAug 3, 2026
- Record low
- 40°FAug 10, 1912
- Chance of a freeze
- 0%
- Days of 90°F or more
- 9.9
- Daylight
- 14 h 15 min to 13 h 06 min
- Cloud cover
- 60%
- Humidity
- 53%
- Dew point
- 39°F
- Wind
- 5.1 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.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Aug 1 | 88°F | 58°F | 100°F 1938 | 44°F 1995 | 37% | 0% |
| Aug 2 | 88°F | 57°F | 101°F 2026 | 41°F 1894 | 37% | 0% |
| Aug 3 | 88°F | 57°F | 104°F 2026 | 49°F 1915 | 37% | 0% |
| Aug 4 | 87°F | 57°F | 99°F 1947 | 45°F 1927 | 37% | 0% |
| Aug 5 | 87°F | 57°F | 99°F 2025 | 46°F 2026 | 37% | 0% |
| Aug 6 | 87°F | 57°F | 101°F 1979 | 48°F 2026 | 37% | 0% |
| Aug 7 | 87°F | 57°F | 100°F 2025 | 47°F 1939 | 36% | 0% |
| Aug 8 | 87°F | 57°F | 101°F 1969 | 46°F 1939 | 36% | 0% |
| Aug 9 | 87°F | 57°F | 101°F 1947 | 45°F 1939 | 36% | 0% |
| Aug 10 | 87°F | 57°F | 97°F 1969 | 40°F 1912 | 35% | 0% |
| Aug 11 | 87°F | 56°F | 97°F 1959 | 47°F 1974 | 35% | 0% |
| Aug 12 | 87°F | 56°F | 99°F 1996 | 47°F 2004 | 35% | 0% |
| Aug 13 | 86°F | 56°F | 100°F 2025 | 44°F 2002 | 35% | 0% |
| Aug 14 | 86°F | 56°F | 99°F 1935 | 48°F 2004 | 34% | 0% |
| Aug 15 | 86°F | 56°F | 97°F 1988 | 47°F 1978 | 34% | 0% |
| Aug 16 | 86°F | 56°F | 100°F 2002 | 47°F 1975 | 34% | |
| Aug 17 | 86°F | 56°F | 97°F 1948 | 45°F 2008 | 34% | |
| Aug 18 | 86°F | 55°F | 98°F 2002 | 48°F 1987 | 33% | |
| Aug 19 | 86°F | 55°F | 96°F 2013 | 43°F 1939 | 33% | |
| Aug 20 | 86°F | 55°F | 98°F 2019 | 43°F 2016 | 33% | |
| Aug 21 | 86°F | 55°F | 101°F 2026 | 44°F 1920 | 32% | |
| Aug 22 | 85°F | 55°F | 97°F 1949 | 46°F 1904 | 32% | |
| Aug 23 | 85°F | 55°F | 98°F 2011 | 44°F 2015 | 31% | |
| Aug 24 | 85°F | 54°F | 102°F 1936 | 45°F 1968 | 31% | |
| Aug 25 | 85°F | 54°F | 97°F 2019 | 43°F 1934 | 31% | |
| Aug 26 | 85°F | 54°F | 96°F 1953 | 44°F 1894 | 30% | |
| Aug 27 | 85°F | 54°F | 96°F 1926 | 42°F 1992 | 30% | |
| Aug 28 | 85°F | 54°F | 97°F 2026 | 40°F 2004 | 30% | |
| Aug 29 | 84°F | 53°F | 97°F 1954 | 44°F 2004 | 30% | |
| Aug 30 | 84°F | 53°F | 96°F 1948 | 46°F 1944 | 29% | |
| Aug 31 | 84°F | 53°F | 96°F 1954 | 42°F 1932 | 29% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- August 1
- sunrise 6:00 AM, sunset 8:15 PM
- August 31
- sunrise 6:28 AM, sunset 7:34 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00050848 (Boulder), public domain. Records: NOAA GHCN-Daily, station USC00050848, 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.