Ukiah weather in September: Ukiah, California: normal highs, lows, rain and records for September
Ukiah in September has a normal high of 89°F and a normal low of 51°F, a daily mean of 70°F, falling from 92°F on the 1st to 85°F by the 30th. Measurable precipitation falls on 1 days in a normal September, 0.16 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 32°C and low of 10°C, 4 mm of precipitation in September.
- NOAA stationUkiah Municipal Airport
- Station IDUSW00023275
- Location39.13°N 123.20°W
- Elevation601 ft (183 m)
- Population16,067
- Jan 58° 37°
- Feb 61° 39°
- Mar 65° 41°
- Apr 69° 43°
- May 78° 48°
- Jun 86° 52°
- Jul 94° 56°
- Aug 94° 55°
- Sep 89° 51°
- Oct 79° 45°
- Nov 65° 40°
- Dec 57° 36°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Ukiah in September?
The normal high is 89°F and the normal low 51°F, for a daily mean of 69.8°F. September is 4.3°F cooler than August and 7.8°F warmer than October. September is the 3rd warmest month of the year in Ukiah and the 10th wettest. Across the month the normal high falls 7°F, from 92°F on September 1 to 85°F on September 30. From one year to the next September's mean temperature typically moves about 1.4°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 68°F and 71°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 11%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 92°F | 53°F | 2% | 1% |
| September 8 | 91°F | 52°F | 3% | 2% |
| September 15 | 89°F | 51°F | 5% | 3% |
| September 22 | 88°F | 50°F | 8% | 4% |
| September 30 | 85°F | 48°F | 11% | 5% |
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 | 92°F | 53°F | 2% | 1% | 13 h 10 min |
| September 2 | 92°F | 53°F | 2% | 1% | 13 h |
| September 3 | 91°F | 53°F | 2% | 1% | 13 h |
| September 4 | 91°F | 53°F | 2% | 1% | 13 h |
| September 5 | 91°F | 53°F | 3% | 1% | 13 h |
| September 6 | 91°F | 52°F | 3% | 1% | 12 h 50 min |
| September 7 | 91°F | 52°F | 3% | 1% | 12 h 50 min |
| September 8 | 91°F | 52°F | 3% | 2% | 12 h 50 min |
| September 9 | 90°F | 52°F | 3% | 2% | 12 h 50 min |
| September 10 | 90°F | 52°F | 4% | 2% | 12 h 40 min |
| September 11 | 90°F | 52°F | 4% | 2% | 12 h 40 min |
| September 12 | 90°F | 51°F | 4% | 2% | 12 h 40 min |
| September 13 | 90°F | 51°F | 5% | 2% | 12 h 40 min |
| September 14 | 90°F | 51°F | 5% | 2% | 12 h 30 min |
| September 15 | 89°F | 51°F | 5% | 3% | 12 h 30 min |
| September 16 | 89°F | 51°F | 6% | 3% | 12 h 30 min |
| September 17 | 89°F | 51°F | 6% | 3% | 12 h 30 min |
| September 18 | 89°F | 50°F | 6% | 3% | 12 h 20 min |
| September 19 | 88°F | 50°F | 7% | 3% | 12 h 20 min |
| September 20 | 88°F | 50°F | 7% | 3% | 12 h 20 min |
| September 21 | 88°F | 50°F | 7% | 4% | 12 h 20 min |
| September 22 | 88°F | 50°F | 8% | 4% | 12 h 10 min |
| September 23 | 87°F | 49°F | 8% | 4% | 12 h 10 min |
| September 24 | 87°F | 49°F | 8% | 4% | 12 h 10 min |
| September 25 | 87°F | 49°F | 9% | 4% | 12 h 10 min |
| September 26 | 87°F | 49°F | 9% | 5% | 12 h |
| September 27 | 86°F | 49°F | 9% | 5% | 12 h |
| September 28 | 86°F | 48°F | 10% | 5% | 12 h |
| September 29 | 86°F | 48°F | 10% | 5% | 12 h |
| September 30 | 85°F | 48°F | 11% | 5% | 11 h 50 min |
- Normal high
- 89°FSeptember average
- Normal low
- 51°FSeptember average
- Precipitation
- 0.16 inmonth total
- Days with precipitation
- 10.01 inch or more
- Days at 90°F or more
- 15
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 29
- Days at 80°F or more
- 24
- Sunshine
- 90%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00023275; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Ukiah in September?
On a given September day the chance of 0.01 inch or more is 6% on average, highest around September 30 (11%). In all, 0.16 in falls on 1 days of a normal September.
In a normal September in Ukiah, 15 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00023275.
How humid and windy is Ukiah in September?
At 3 p.m. the normal temperature is 83°F with 24% relative humidity and a dew point of 42°F; at 6 a.m. it is 50°F with 80% humidity. The wind averages 3.7 mph, most often from the west-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. | 50°F | 44°F | 80% | 0.8 mph | – |
| 9 a.m. | 62°F | 46°F | 56% | 1.7 mph | – |
| noon | 78°F | 44°F | 30% | 4.4 mph | 88% |
| 3 p.m. | 83°F | 42°F | 24% | 7.6 mph | 89% |
| 6 p.m. | 72°F | 44°F | 37% | 4.7 mph | – |
| 9 p.m. | 62°F | 45°F | 54% | – | – |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00023275. 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 Ukiah?
The warmest September temperature on Ukiah's official record (since 1893) is 117°F, on September 6, 2022; the coldest is 30°F, on September 18, 1902. The wettest September brought 3.51 in (1957).
The September mean against the 1991-2020 normal of 69.8°F: 2021 72.4°F (+2.6), 2022 72.7°F (+2.9), 2023 68.8°F (−1.0), 2024 73.3°F (+3.5), 2025 71.7°F (+1.9). 4 of 5 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 72.4°F | +2.6°F | 0.06 in |
| 2022 | 72.7°F | +2.9°F | 1.98 in |
| 2023 | 68.8°F | −1.0°F | 0.20 in |
| 2024 | 73.3°F | +3.5°F | 0.00 in |
| 2025 | 71.7°F | +1.9°F | 1.18 in |
Source: records: ACIS, NWS threaded record UKIthr; recent months: ACIS, station USW00023275. Records and recent months use complete months only.
How does September in Ukiah 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; Ukiah's is 89°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.