La Mesa Weather in September
Average highs run from 92°F on September 1 to 85°F on September 30, and lows from 66°F to 56°F. Normal precipitation for the month is 1.41 in over about 5 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
- 88°F
- Average low
- 61°F
- Precipitation
- 1.41 in
- Record high
- 102°FSep 7, 2023
- Record low
- 41°FSep 29, 2013
- Chance of a freeze
- 0%
- Days of 90°F or more
- 14.4
- Daylight
- 12 h 49 min to 11 h 53 min
- Cloud cover
- 38%
- Humidity
- 45%
- Dew point
- 49°F
- Wind
- 7.8 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 | 92°F | 66°F | 98°F 2011 | 60°F 2008 | 23% | 0% |
| Sep 2 | 92°F | 65°F | 100°F 2014 | 61°F 2004 | 23% | 0% |
| Sep 3 | 91°F | 65°F | 100°F 2011 | 57°F 2024 | 22% | 0% |
| Sep 4 | 91°F | 65°F | 98°F 2020 | 60°F 2006 | 22% | 0% |
| Sep 5 | 91°F | 65°F | 97°F 2012 | 59°F 2010 | 22% | 0% |
| Sep 6 | 91°F | 64°F | 101°F 2023 | 59°F 2006 | 21% | 0% |
| Sep 7 | 91°F | 64°F | 102°F 2023 | 58°F 2006 | 21% | 0% |
| Sep 8 | 90°F | 64°F | 102°F 2023 | 59°F 2008 | 21% | 0% |
| Sep 9 | 90°F | 64°F | 101°F 2023 | 52°F 2020 | 20% | 0% |
| Sep 10 | 90°F | 63°F | 101°F 2023 | 49°F 2020 | 20% | 0% |
| Sep 11 | 90°F | 63°F | 100°F 2026 | 53°F 2020 | 20% | 0% |
| Sep 12 | 89°F | 63°F | 98°F 2026 | 56°F 2020 | 19% | 0% |
| Sep 13 | 89°F | 62°F | 98°F 2017 | 56°F 2014 | 19% | 0% |
| Sep 14 | 89°F | 62°F | 96°F 2017 | 51°F 2012 | 19% | 0% |
| Sep 15 | 89°F | 62°F | 94°F 2004 | 47°F 2012 | 18% | 0% |
| Sep 16 | 88°F | 61°F | 96°F 2004 | 50°F 2012 | 18% | 0% |
| Sep 17 | 88°F | 61°F | 97°F 2005 | 48°F 2008 | 18% | 0% |
| Sep 18 | 88°F | 61°F | 96°F 2005 | 52°F 2006 | 17% | 0% |
| Sep 19 | 88°F | 60°F | 98°F 2005 | 49°F 2006 | 17% | 0% |
| Sep 20 | 87°F | 60°F | 95°F 2016 | 53°F 2002 | 16% | 0% |
| Sep 21 | 87°F | 59°F | 95°F 2016 | 56°F 2002 | 16% | 0% |
| Sep 22 | 87°F | 59°F | 96°F 2005 | 52°F 2009 | 16% | 0% |
| Sep 23 | 87°F | 59°F | 96°F 2005 | 52°F 2009 | 15% | 0% |
| Sep 24 | 86°F | 58°F | 96°F 2005 | 50°F 2013 | 15% | 0% |
| Sep 25 | 86°F | 58°F | 97°F 2020 | 52°F 2006 | 15% | 0% |
| Sep 26 | 86°F | 57°F | 98°F 2005 | 52°F 2016 | 14% | 0% |
| Sep 27 | 85°F | 57°F | 96°F 2005 | 52°F 2016 | 14% | 0% |
| Sep 28 | 85°F | 56°F | 96°F 2005 | 49°F 2013 | 14% | 0% |
| Sep 29 | 85°F | 56°F | 94°F 2010 | 41°F 2013 | 14% | 0% |
| Sep 30 | 85°F | 56°F | 94°F 2003 | 48°F 2006 | 14% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- September 1
- sunrise 6:42 AM, sunset 7:31 PM
- September 30
- sunrise 7:00 AM, sunset 6:53 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00298535 (State Univ), public domain. Records: NOAA GHCN-Daily, station USC00298127, 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.