Mono County Weather in September
Average highs run from 80°F on September 1 to 71°F on September 30, and lows from 49°F to 41°F. Normal precipitation for the month is 0.31 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
- 76°F
- Average low
- 46°F
- Precipitation
- 0.31 in
- Record high
- 83°FSep 2, 2014
- Record low
- 21°FSep 21, 2004
- Chance of a freeze
- 17%
- Daylight
- 12 h 59 min to 11 h 50 min
- Cloud cover
- 24%
- Humidity
- 33%
- Dew point
- 26°F
- Wind
- 6.7 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 | 80°F | 49°F | 81°F 1996 | 34°F 1999 | 7% | 0% |
| Sep 2 | 80°F | 49°F | 83°F 2014 | 30°F 2008 | 7% | 0% |
| Sep 3 | 80°F | 49°F | 82°F 2017 | 30°F 1999 | 7% | 0% |
| Sep 4 | 80°F | 49°F | 81°F 2010 | 25°F 2004 | 7% | 0% |
| Sep 5 | 79°F | 48°F | 78°F 1994 | 25°F 2004 | 7% | 0% |
| Sep 6 | 79°F | 48°F | 81°F 2008 | 26°F 2000 | 7% | 0% |
| Sep 7 | 79°F | 48°F | 80°F 2001 | 27°F 2000 | 7% | 0% |
| Sep 8 | 79°F | 48°F | 81°F 2008 | 27°F 2002 | 7% | 0% |
| Sep 9 | 78°F | 48°F | 80°F 2015 | 29°F 2002 | 7% | 0% |
| Sep 10 | 78°F | 47°F | 81°F 2018 | 29°F 2010 | 7% | 0% |
| Sep 11 | 78°F | 47°F | 82°F 2015 | 31°F 2002 | 7% | |
| Sep 12 | 77°F | 47°F | 82°F 2015 | 25°F 2005 | 7% | |
| Sep 13 | 77°F | 46°F | 79°F 2003 | 26°F 2005 | 7% | |
| Sep 14 | 77°F | 46°F | 80°F 1995 | 26°F 1994 | 7% | |
| Sep 15 | 76°F | 46°F | 80°F 1995 | 26°F 1996 | 7% | |
| Sep 16 | 76°F | 46°F | 77°F 1995 | 22°F 2006 | 7% | |
| Sep 17 | 76°F | 45°F | 78°F 2009 | 25°F 1996 | 7% | |
| Sep 18 | 75°F | 45°F | 79°F 2014 | 25°F 1996 | 7% | |
| Sep 19 | 75°F | 45°F | 80°F 2000 | 28°F 1996 | 8% | |
| Sep 20 | 75°F | 44°F | 82°F 2000 | 26°F 2004 | 8% | |
| Sep 21 | 74°F | 44°F | 78°F 2000 | 21°F 2004 | 8% | |
| Sep 22 | 74°F | 44°F | 78°F 2003 | 22°F 2004 | 8% | |
| Sep 23 | 74°F | 43°F | 78°F 2002 | 22°F 2004 | 8% | |
| Sep 24 | 73°F | 43°F | 78°F 2002 | 23°F 2017 | 8% | |
| Sep 25 | 73°F | 43°F | 78°F 2003 | 25°F 2005 | 8% | |
| Sep 26 | 72°F | 42°F | 80°F 1999 | 26°F 2017 | 8% | |
| Sep 27 | 72°F | 42°F | 80°F 1999 | 22°F 2013 | 8% | |
| Sep 28 | 72°F | 42°F | 81°F 2003 | 28°F 2005 | 8% | |
| Sep 29 | 71°F | 41°F | 81°F 2010 | 26°F 1995 | 8% | |
| Sep 30 | 71°F | 41°F | 81°F 2010 | 23°F 2009 | 8% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:26 AM, sunset 7:25 PM
- September 30
- sunrise 6:50 AM, sunset 6:40 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00044881 (Lee Vining), public domain. Records: NOAA GHCN-Daily, station USC00045280, 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.