Humboldt County Weather in September
Average highs run from 87°F on September 1 to 76°F on September 30, and lows from 44°F to 35°F. Normal precipitation for the month is 0.51 in over about 2 wet days.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 82°F
- Average low
- 39°F
- Precipitation
- 0.51 in
- Record high
- 106°FSep 6, 2022
- Record low
- 12°FSep 24, 1958
- Chance of a freeze
- 93%
- Days of 90°F or more
- 7.1
- Daylight
- 13 h 06 min to 11 h 48 min
- Cloud cover
- 32%
- Humidity
- 31%
- Dew point
- 28°F
- Wind
- 6.3 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.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Sep 1 | 87°F | 44°F | 101°F 1950 | 28°F 1887 | 6% | 0% |
| Sep 2 | 87°F | 43°F | 103°F 1950 | 26°F 1973 | 6% | 0% |
| Sep 3 | 87°F | 43°F | 103°F 2017 | 29°F 1961 | 7% | 0% |
| Sep 4 | 86°F | 43°F | 104°F 2020 | 28°F 1999 | 7% | 0% |
| Sep 5 | 86°F | 43°F | 104°F 2020 | 30°F 1999 | 7% | 0% |
| Sep 6 | 86°F | 42°F | 106°F 2022 | 24°F 2015 | 7% | 0% |
| Sep 7 | 85°F | 42°F | 105°F 2022 | 28°F 1897 | 7% | 0% |
| Sep 8 | 85°F | 42°F | 99°F 2021 | 29°F 1929 | 7% | 0% |
| Sep 9 | 85°F | 42°F | 101°F 2021 | 29°F 1928 | 7% | 0% |
| Sep 10 | 84°F | 41°F | 98°F 1990 | 28°F 1916 | 7% | 0% |
| Sep 11 | 84°F | 41°F | 96°F 1944 | 24°F 2005 | 7% | 0% |
| Sep 12 | 84°F | 41°F | 96°F 1953 | 25°F 1974 | 8% | 0% |
| Sep 13 | 83°F | 40°F | 97°F 1971 | 22°F 1914 | 8% | 0% |
| Sep 14 | 83°F | 40°F | 97°F 2000 | 15°F 1970 | 8% | 0% |
| Sep 15 | 83°F | 40°F | 95°F 1937 | 26°F 1970 | 8% | 0% |
| Sep 16 | 82°F | 39°F | 95°F 1937 | 22°F 1970 | 8% | 0% |
| Sep 17 | 82°F | 39°F | 97°F 1929 | 21°F 1965 | 9% | 0% |
| Sep 18 | 81°F | 39°F | 93°F 1898 | 17°F 1965 | 9% | 0% |
| Sep 19 | 81°F | 38°F | 97°F 1939 | 18°F 1971 | 9% | 0% |
| Sep 20 | 80°F | 38°F | 96°F 1939 | 20°F 1978 | 9% | 0% |
| Sep 21 | 80°F | 38°F | 92°F 1954 | 21°F 1986 | 9% | 0% |
| Sep 22 | 80°F | 37°F | 94°F 1966 | 16°F 1895 | 9% | 0% |
| Sep 23 | 79°F | 37°F | 93°F 1987 | 20°F 2017 | 9% | 0% |
| Sep 24 | 79°F | 37°F | 93°F 2011 | 12°F 1958 | 9% | 0% |
| Sep 25 | 78°F | 36°F | 92°F 2009 | 18°F 1972 | 9% | 0% |
| Sep 26 | 78°F | 36°F | 93°F 1963 | 17°F 1934 | 9% | 0% |
| Sep 27 | 77°F | 36°F | 94°F 1963 | 19°F 1900 | 9% | 0% |
| Sep 28 | 77°F | 35°F | 95°F 1963 | 19°F 1959 | 10% | 0% |
| Sep 29 | 76°F | 35°F | 93°F 1963 | 17°F 1954 | 10% | 0% |
| Sep 30 | 76°F | 35°F | 95°F 2010 | 17°F 1950 | 10% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:19 AM, sunset 7:25 PM
- September 30
- sunrise 6:48 AM, sunset 6:36 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00265818 (Orovada 3 W), public domain. Records: NOAA GHCN-Daily, station USW00024128, 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.