Mount Shasta weather in September: Mount Shasta, California: normal highs, lows, rain and records for September
Mount Shasta in September has a normal high of 78°F and a normal low of 45°F, a daily mean of 62°F, falling from 83°F on the 1st to 73°F by the 30th. Measurable precipitation falls on 3 days in a normal September, 0.51 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 26°C and low of 7°C, 13 mm of precipitation in September.
- NOAA stationMount Shasta
- Station IDUSW00024215
- Location41.33°N 122.33°W
- Elevation3,535 ft (1,078 m)
- From the center1 miles
- Population3,124
- Jan 44° 29°
- Feb 47° 29°
- Mar 53° 32°
- Apr 59° 35°
- May 69° 41°
- Jun 76° 47°
- Jul 85° 52°
- Aug 85° 50°
- Sep 78° 45°
- Oct 65° 38°
- Nov 51° 31°
- Dec 42° 28°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Mount Shasta in September?
The normal high is 78°F and the normal low 45°F, for a daily mean of 61.5°F. September is 5.8°F cooler than August and 10.4°F warmer than October. September is the 4th warmest month of the year in Mount Shasta and the 10th wettest. Across the month the normal high falls 10°F, from 83°F on September 1 to 73°F on September 30. From one year to the next September's mean temperature typically moves about 1.8°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 60°F and 63°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 14%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 83°F | 47°F | 7% | 3% |
| September 8 | 81°F | 46°F | 8% | 4% |
| September 15 | 79°F | 45°F | 10% | 4% |
| September 22 | 76°F | 43°F | 12% | 6% |
| September 30 | 73°F | 41°F | 14% | 7% |
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 | 83°F | 47°F | 7% | 3% | 13 h 10 min |
| September 2 | 82°F | 47°F | 7% | 3% | 13 h 10 min |
| September 3 | 82°F | 47°F | 7% | 3% | 13 h |
| September 4 | 82°F | 47°F | 7% | 3% | 13 h |
| September 5 | 82°F | 47°F | 7% | 3% | 13 h |
| September 6 | 82°F | 47°F | 8% | 3% | 13 h |
| September 7 | 81°F | 46°F | 8% | 3% | 12 h 50 min |
| September 8 | 81°F | 46°F | 8% | 4% | 12 h 50 min |
| September 9 | 81°F | 46°F | 9% | 4% | 12 h 50 min |
| September 10 | 81°F | 46°F | 9% | 4% | 12 h 50 min |
| September 11 | 80°F | 46°F | 9% | 4% | 12 h 40 min |
| September 12 | 80°F | 45°F | 9% | 4% | 12 h 40 min |
| September 13 | 80°F | 45°F | 10% | 4% | 12 h 40 min |
| September 14 | 79°F | 45°F | 10% | 4% | 12 h 40 min |
| September 15 | 79°F | 45°F | 10% | 4% | 12 h 30 min |
| September 16 | 79°F | 45°F | 10% | 5% | 12 h 30 min |
| September 17 | 78°F | 44°F | 11% | 5% | 12 h 30 min |
| September 18 | 78°F | 44°F | 11% | 5% | 12 h 20 min |
| September 19 | 78°F | 44°F | 11% | 5% | 12 h 20 min |
| September 20 | 77°F | 44°F | 11% | 5% | 12 h 20 min |
| September 21 | 77°F | 44°F | 12% | 5% | 12 h 20 min |
| September 22 | 76°F | 43°F | 12% | 6% | 12 h 10 min |
| September 23 | 76°F | 43°F | 12% | 6% | 12 h 10 min |
| September 24 | 76°F | 43°F | 12% | 6% | 12 h 10 min |
| September 25 | 75°F | 43°F | 13% | 6% | 12 h 10 min |
| September 26 | 75°F | 42°F | 13% | 6% | 12 h |
| September 27 | 74°F | 42°F | 13% | 6% | 12 h |
| September 28 | 74°F | 42°F | 13% | 7% | 12 h |
| September 29 | 73°F | 42°F | 14% | 7% | 11 h 50 min |
| September 30 | 73°F | 41°F | 14% | 7% | 11 h 50 min |
- Normal high
- 78°FSeptember average
- Normal low
- 45°FSeptember average
- Precipitation
- 0.51 inmonth total
- Days with precipitation
- 30.01 inch or more
- Days at 90°F or more
- 3
- Nights at 32°F or colder
- 1
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 25
- Days at 80°F or more
- 17
- Sunshine
- 92%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00024215; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Mount Shasta in September?
On a given September day the chance of 0.01 inch or more is 10% on average, highest around September 30 (14%). In all, 0.51 in falls on 3 days of a normal September.
In a normal September in Mount Shasta, 3 days reach 90°F and 1 nights fall to freezing.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00024215.
How humid and windy is Mount Shasta in September?
At 3 p.m. the normal temperature is 72°F with 30% relative humidity and a dew point of 38°F; at 6 a.m. it is 44°F with 72% humidity. The wind averages 2.8 mph, most often from the northwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 44°F | 36°F | 72% | 1.9 mph | – |
| 9 a.m. | 60°F | 41°F | 49% | 3.0 mph | – |
| noon | 70°F | 40°F | 34% | 4.3 mph | – |
| 3 p.m. | 72°F | 38°F | 30% | 4.3 mph | – |
| 6 p.m. | 62°F | 39°F | 43% | 2.5 mph | – |
| 9 p.m. | 53°F | 38°F | 57% | 2.5 mph | – |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00024215. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in Mount Shasta?
The warmest September temperature on Mount Shasta's official record (since 1948) is 103°F, on September 2, 1955; the coldest is 25°F, on September 17, 1965. The wettest September brought 6.83 in (1957).
The September mean against the 1991-2020 normal of 61.5°F: 2021 62.9°F (+1.4), 2022 64.5°F (+3.0), 2023 60.4°F (−1.1), 2024 64.9°F (+3.4), 2025 63.0°F (+1.5), 2026 59.1°F (−2.4). 4 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 62.9°F | +1.4°F | 0.83 in |
| 2022 | 64.5°F | +3.0°F | 1.09 in |
| 2023 | 60.4°F | −1.1°F | 1.61 in |
| 2024 | 64.9°F | +3.4°F | 0.43 in |
| 2025 | 63.0°F | +1.5°F | 0.78 in |
| 2026 | 59.1°F | −2.4°F | 0.42 in |
Source: records: ACIS, NWS threaded record MHSthr; recent months: ACIS, station USW00024215. Records and recent months use complete months only.
How does September in Mount Shasta 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; Mount Shasta's is 78°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Mount Shasta in August85°F by day, 50°F at night
- Mount Shasta in October65°F by day, 38°F at night
- Mount Shasta 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