O'Brien Weather in September
Average highs run from 91°F on September 1 to 82°F on September 30, and lows from 47°F to 42°F. Normal precipitation for the month is 0.83 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
- 87°F
- Average low
- 44°F
- Precipitation
- 0.83 in
- Record high
- 98°FSep 20, 2002
- Record low
- 39°FSep 23, 2005
- Chance of a freeze
- 21%
- Days of 90°F or more
- 14.0
- Daylight
- 13 h 07 min to 11 h 47 min
- Cloud cover
- 34%
- Humidity
- 54%
- Dew point
- 41°F
- Wind
- 4.3 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 | 91°F | 47°F | 94°F 2002 | 46°F 2005 | 6% | 0% |
| Sep 2 | 91°F | 47°F | 86°F 2002 | 47°F 2008 | 6% | 0% |
| Sep 3 | 91°F | 46°F | 83°F 2017 | 46°F 2008 | 6% | 0% |
| Sep 4 | 90°F | 46°F | 85°F 2003 | 45°F 2002 | 7% | 0% |
| Sep 5 | 90°F | 46°F | 82°F 2014 | 45°F 2002 | 7% | 0% |
| Sep 6 | 90°F | 46°F | 93°F 2008 | 43°F 2002 | 7% | 0% |
| Sep 7 | 90°F | 46°F | 81°F 2007 | 44°F 2002 | 7% | 0% |
| Sep 8 | 90°F | 46°F | 80°F 2004 | 46°F 2002 | 8% | 0% |
| Sep 9 | 89°F | 46°F | 86°F 2020 | 47°F 2003 | 8% | 0% |
| Sep 10 | 89°F | 45°F | 83°F 2013 | 45°F 2010 | 8% | 0% |
| Sep 11 | 89°F | 45°F | 74°F 2017 | 46°F 2010 | 8% | 0% |
| Sep 12 | 89°F | 45°F | 78°F 2003 | 44°F 2008 | 8% | 0% |
| Sep 13 | 88°F | 45°F | 82°F 2016 | 45°F 2008 | 9% | 0% |
| Sep 14 | 88°F | 45°F | 93°F 2003 | 46°F 2014 | 9% | 0% |
| Sep 15 | 88°F | 45°F | 79°F 2003 | 47°F 2008 | 9% | 0% |
| Sep 16 | 87°F | 44°F | 71°F 2020 | 47°F 2003 | 10% | 0% |
| Sep 17 | 87°F | 44°F | 71°F 2004 | 45°F 2003 | 10% | 0% |
| Sep 18 | 87°F | 44°F | 75°F 2009 | 43°F 2003 | 10% | 0% |
| Sep 19 | 87°F | 44°F | 88°F 2002 | 46°F 2008 | 11% | 0% |
| Sep 20 | 86°F | 44°F | 98°F 2002 | 45°F 2004 | 11% | 0% |
| Sep 21 | 86°F | 43°F | 97°F 2002 | 44°F 2004 | 11% | 0% |
| Sep 22 | 85°F | 43°F | 84°F 2009 | 43°F 2005 | 12% | 0% |
| Sep 23 | 85°F | 43°F | 88°F 2003 | 39°F 2005 | 12% | 0% |
| Sep 24 | 85°F | 43°F | 86°F 2006 | 44°F 2005 | 12% | 0% |
| Sep 25 | 84°F | 43°F | 79°F 2018 | 43°F 2007 | 13% | 0% |
| Sep 26 | 84°F | 42°F | 81°F 2005 | 45°F 2002 | 13% | 0% |
| Sep 27 | 83°F | 42°F | 78°F 2017 | 39°F 2003 | 14% | 0% |
| Sep 28 | 83°F | 42°F | 90°F 2020 | 43°F 2005 | 14% | 0% |
| Sep 29 | 82°F | 42°F | 93°F 2020 | 40°F 2007 | 15% | 0% |
| Sep 30 | 82°F | 42°F | 77°F 2020 | 41°F 2007 | 15% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:41 AM, sunset 7:48 PM
- September 30
- sunrise 7:11 AM, sunset 6:58 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00351448 (Cave Junction 1 Wnw), public domain. Records: NOAA GHCN-Daily, station USC00351058, 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.