National City Weather in September
Average highs run from 78°F on September 1 to 76°F on September 30, and lows from 65°F to 62°F. Normal precipitation for the month is 0.09 in over about 1 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
- 77°F
- Average low
- 64°F
- Precipitation
- 0.09 in
- Record high
- 111°FSep 26, 1963
- Record low
- 51°FSep 26, 1948
- Chance of a freeze
- 0%
- Days of 90°F or more
- 1.9
- Daylight
- 12 h 50 min to 11 h 52 min
- Cloud cover
- 23%
- Humidity
- 58%
- Dew point
- 53°F
- Wind
- 5.8 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 | 78°F | 65°F | 104°F 1955 | 59°F 1941 | 1% |
| Sep 2 | 78°F | 65°F | 99°F 1955 | 59°F 1964 | 1% |
| Sep 3 | 78°F | 65°F | 95°F 2022 | 59°F 1964 | 1% |
| Sep 4 | 78°F | 65°F | 107°F 1988 | 60°F 1940 | 1% |
| Sep 5 | 78°F | 65°F | 97°F 1988 | 59°F 1940 | 2% |
| Sep 6 | 78°F | 65°F | 100°F 2020 | 56°F 1942 | 2% |
| Sep 7 | 78°F | 65°F | 95°F 2026 | 58°F 1956 | 2% |
| Sep 8 | 78°F | 65°F | 100°F 1984 | 58°F 1943 | 2% |
| Sep 9 | 78°F | 65°F | 96°F 1956 | 58°F 1961 | 2% |
| Sep 10 | 78°F | 65°F | 96°F 2015 | 59°F 1950 | 2% |
| Sep 11 | 78°F | 65°F | 102°F 1959 | 58°F 1952 | 2% |
| Sep 12 | 78°F | 65°F | 94°F 1971 | 55°F 1952 | 2% |
| Sep 13 | 77°F | 65°F | 92°F 1963 | 56°F 1952 | 2% |
| Sep 14 | 77°F | 64°F | 90°F 1989 | 55°F 1939 | 2% |
| Sep 15 | 77°F | 64°F | 101°F 2012 | 56°F 1939 | 2% |
| Sep 16 | 77°F | 64°F | 97°F 1979 | 58°F 1940 | 2% |
| Sep 17 | 77°F | 64°F | 93°F 1939 | 56°F 1943 | 2% |
| Sep 18 | 77°F | 64°F | 95°F 1939 | 57°F 1943 | 2% |
| Sep 19 | 77°F | 64°F | 97°F 1939 | 56°F 1942 | 2% |
| Sep 20 | 77°F | 64°F | 100°F 1939 | 55°F 1944 | 2% |
| Sep 21 | 77°F | 64°F | 106°F 1939 | 53°F 1997 | 2% |
| Sep 22 | 77°F | 63°F | 102°F 1939 | 53°F 1944 | 2% |
| Sep 23 | 77°F | 63°F | 103°F 1975 | 52°F 1941 | 2% |
| Sep 24 | 77°F | 63°F | 99°F 1978 | 55°F 1944 | 2% |
| Sep 25 | 77°F | 63°F | 101°F 1978 | 55°F 1948 | 2% |
| Sep 26 | 76°F | 63°F | 111°F 1963 | 51°F 1948 | 2% |
| Sep 27 | 76°F | 63°F | 104°F 1963 | 55°F 1948 | 2% |
| Sep 28 | 76°F | 62°F | 99°F 1963 | 56°F 1945 | 2% |
| Sep 29 | 76°F | 62°F | 90°F 1999 | 54°F 1948 | 2% |
| Sep 30 | 76°F | 62°F | 96°F 2020 | 55°F 1951 | 3% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:23 AM, sunset 7:13 PM
- September 30
- sunrise 6:42 AM, sunset 6:34 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00041758 (Chula Vista), public domain. Records: NOAA GHCN-Daily, station USW00023188, 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.