Modoc County Weather in September
Average highs run from 84°F on September 1 to 74°F on September 30, and lows from 41°F to 33°F. Normal precipitation for the month is 0.35 in over about 3 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
- 80°F
- Average low
- 37°F
- Precipitation
- 0.35 in
- Record high
- 102°FSep 4, 2020
- Record low
- 21°FSep 24, 2000
- Chance of a freeze
- 93%
- Days of 90°F or more
- 4.2
- Daylight
- 13 h 07 min to 11 h 47 min
- Cloud cover
- 30%
- Humidity
- 41%
- Dew point
- 32°F
- Wind
- 6.9 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 |
|---|---|---|---|---|---|
| Sep 1 | 84°F | 41°F | 98°F 2022 | 29°F 1999 | 8% |
| Sep 2 | 84°F | 41°F | 99°F 2017 | 30°F 2011 | 8% |
| Sep 3 | 84°F | 40°F | 99°F 2017 | 30°F 2021 | 8% |
| Sep 4 | 84°F | 40°F | 102°F 2020 | 27°F 2000 | 8% |
| Sep 5 | 83°F | 40°F | 100°F 2017 | 30°F 2016 | 8% |
| Sep 6 | 83°F | 40°F | 102°F 2022 | 26°F 2000 | 8% |
| Sep 7 | 83°F | 39°F | 99°F 2022 | 28°F 2000 | 8% |
| Sep 8 | 83°F | 39°F | 94°F 2021 | 25°F 2002 | 9% |
| Sep 9 | 82°F | 39°F | 94°F 2021 | 27°F 2002 | 9% |
| Sep 10 | 82°F | 39°F | 94°F 2015 | 26°F 2005 | 9% |
| Sep 11 | 82°F | 38°F | 97°F 2015 | 29°F 2005 | 9% |
| Sep 12 | 81°F | 38°F | 95°F 2015 | 27°F 2005 | 9% |
| Sep 13 | 81°F | 38°F | 90°F 2012 | 27°F 2005 | 10% |
| Sep 14 | 81°F | 38°F | 91°F 2008 | 26°F 2018 | 10% |
| Sep 15 | 80°F | 38°F | 92°F 2008 | 26°F 2016 | 10% |
| Sep 16 | 80°F | 37°F | 94°F 2008 | 25°F 2018 | 10% |
| Sep 17 | 80°F | 37°F | 88°F 2014 | 23°F 2018 | 10% |
| Sep 18 | 79°F | 37°F | 92°F 2009 | 25°F 2003 | 10% |
| Sep 19 | 79°F | 36°F | 90°F 2012 | 27°F 2013 | 11% |
| Sep 20 | 78°F | 36°F | 91°F 2012 | 26°F 2018 | 11% |
| Sep 21 | 78°F | 36°F | 90°F 2012 | 22°F 2004 | 11% |
| Sep 22 | 78°F | 36°F | 90°F 2001 | 25°F 2017 | 11% |
| Sep 23 | 77°F | 35°F | 92°F 2009 | 23°F 2017 | 11% |
| Sep 24 | 77°F | 35°F | 92°F 2009 | 21°F 2000 | 11% |
| Sep 25 | 76°F | 35°F | 94°F 2009 | 21°F 2005 | 11% |
| Sep 26 | 76°F | 35°F | 92°F 2003 | 24°F 2002 | 12% |
| Sep 27 | 75°F | 34°F | 93°F 2010 | 22°F 2013 | 12% |
| Sep 28 | 75°F | 34°F | 91°F 2003 | 25°F 1999 | 12% |
| Sep 29 | 74°F | 34°F | 91°F 2010 | 26°F 2005 | 12% |
| Sep 30 | 74°F | 33°F | 93°F 2010 | 26°F 2007 | 13% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:29 AM, sunset 7:36 PM
- September 30
- sunrise 6:59 AM, sunset 6:46 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00094299 (Alturas Muni AP), public domain. Records: NOAA GHCN-Daily, station USW00094299, 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.