Big Bear Lake weather in September: Big Bear Lake, California: normal highs, lows, rain and records for September
Big Bear Lake in September has a normal high of 73°F and a normal low of 44°F, a daily mean of 59°F, falling from 77°F on the 1st to 69°F by the 30th. Measurable precipitation falls on 2 days in a normal September, 0.40 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 23°C and low of 7°C, 10 mm of precipitation in September.
- NOAA stationBig Bear Lake
- Station IDUSC00040741
- Location34.24°N 116.92°W
- Elevation6,753 ft (2,058 m)
- Population5,044
- Jan 46° 24°
- Feb 46° 24°
- Mar 51° 27°
- Apr 57° 31°
- May 66° 37°
- Jun 75° 44°
- Jul 80° 51°
- Aug 79° 50°
- Sep 73° 44°
- Oct 63° 35°
- Nov 54° 28°
- Dec 46° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Big Bear Lake in September?
The normal high is 73°F and the normal low 44°F, for a daily mean of 58.5°F. September is 5.6°F cooler than August and 9.3°F warmer than October. September is the 4th warmest month of the year in Big Bear Lake and the 11th wettest. Across the month the normal high falls 8°F, from 77°F on September 1 to 69°F on September 30. From one year to the next September's mean temperature typically moves about 1.6°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 57°F and 60°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 10%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 77°F | 47°F | 10% | 5% |
| September 8 | 75°F | 46°F | 8% | 5% |
| September 15 | 73°F | 44°F | 7% | 4% |
| September 22 | 71°F | 42°F | 6% | 3% |
| September 30 | 69°F | 40°F | 5% | 3% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 77°F | 47°F | 10% | 5% | 13 h |
| September 2 | 77°F | 47°F | 10% | 5% | 12 h 50 min |
| September 3 | 76°F | 47°F | 9% | 5% | 12 h 50 min |
| September 4 | 76°F | 47°F | 9% | 5% | 12 h 50 min |
| September 5 | 76°F | 47°F | 9% | 5% | 12 h 50 min |
| September 6 | 76°F | 47°F | 9% | 5% | 12 h 50 min |
| September 7 | 76°F | 46°F | 9% | 5% | 12 h 40 min |
| September 8 | 75°F | 46°F | 8% | 5% | 12 h 40 min |
| September 9 | 75°F | 46°F | 8% | 4% | 12 h 40 min |
| September 10 | 75°F | 46°F | 8% | 4% | 12 h 40 min |
| September 11 | 75°F | 45°F | 8% | 4% | 12 h 30 min |
| September 12 | 74°F | 45°F | 7% | 4% | 12 h 30 min |
| September 13 | 74°F | 45°F | 7% | 4% | 12 h 30 min |
| September 14 | 74°F | 45°F | 7% | 4% | 12 h 30 min |
| September 15 | 73°F | 44°F | 7% | 4% | 12 h 30 min |
| September 16 | 73°F | 44°F | 7% | 4% | 12 h 20 min |
| September 17 | 73°F | 44°F | 6% | 4% | 12 h 20 min |
| September 18 | 73°F | 44°F | 6% | 3% | 12 h 20 min |
| September 19 | 72°F | 43°F | 6% | 3% | 12 h 20 min |
| September 20 | 72°F | 43°F | 6% | 3% | 12 h 20 min |
| September 21 | 72°F | 43°F | 6% | 3% | 12 h 10 min |
| September 22 | 71°F | 42°F | 6% | 3% | 12 h 10 min |
| September 23 | 71°F | 42°F | 5% | 3% | 12 h 10 min |
| September 24 | 71°F | 42°F | 5% | 3% | 12 h 10 min |
| September 25 | 70°F | 41°F | 5% | 3% | 12 h 10 min |
| September 26 | 70°F | 41°F | 5% | 3% | 12 h |
| September 27 | 70°F | 41°F | 5% | 3% | 12 h |
| September 28 | 69°F | 40°F | 5% | 3% | 12 h |
| September 29 | 69°F | 40°F | 5% | 3% | 12 h |
| September 30 | 69°F | 40°F | 5% | 3% | 11 h 50 min |
- Normal high
- 73°FSeptember average
- Normal low
- 44°FSeptember average
- Precipitation
- 0.40 inmonth total
- Days with precipitation
- 20.01 inch or more
- Nights at 32°F or colder
- 1
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 25
- Days at 80°F or more
- 5
- Sunshine
- 95%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00040741; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Big Bear Lake in September?
On a given September day the chance of 0.01 inch or more is 7% on average, highest around September 1 (10%). In all, 0.40 in falls on 2 days of a normal September.
In a normal September in Big Bear Lake, 1 nights fall to freezing.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00040741.
What are the records for September in Big Bear Lake?
The warmest September temperature on this station's record (since 1960) is 87°F, on September 6, 2020; the coldest is 19°F, on September 2, 1964. The wettest September brought 5.03 in (1976).
The September mean against the 1991-2020 normal of 58.5°F: 2021 60.6°F (+2.1), 2022 60.9°F (+2.4), 2023 57.8°F (−0.7), 2024 59.4°F (+0.9), 2025 58.3°F (−0.2). 3 of 5 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 60.6°F | +2.1°F | 0.00 in |
| 2022 | 60.9°F | +2.4°F | 0.88 in |
| 2023 | 57.8°F | −0.7°F | 0.32 in |
| 2024 | 59.4°F | +0.9°F | 0.57 in |
| 2025 | 58.3°F | −0.2°F | 2.34 in |
Source: records: ACIS, station USC00040741; recent months: ACIS, station USC00040741. Records and recent months use complete months only.
How does September in Big Bear Lake compare across California?
Across the 219 places PlainClimate covers in California, September normal highs run from 64°F in Eureka to 104°F in Brawley; Big Bear Lake's is 73°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Big Bear Lake in August79°F by day, 50°F at night
- Big Bear Lake in October63°F by day, 35°F at night
- Big Bear Lake through the yearEvery month, frost dates, records and recent years
- California in SeptemberThe statewide normal and the warmest and coolest places
- Brawley: California's warmest Septembernormal high 104°F