Modesto weather in September: Modesto, California: normal highs, lows, rain and records for September
Modesto in September has a normal high of 89°F and a normal low of 59°F, a daily mean of 74°F, falling from 92°F on the 1st to 85°F by the 30th. Measurable precipitation falls on 0 days in a normal September, 0.06 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 32°C and low of 15°C, 2 mm of precipitation in September.
- NOAA stationModesto City County Airport
- Station IDUSW00023258
- Location37.62°N 120.95°W
- Elevation73 ft (22 m)
- From the center3 miles
- Population220,592
- Jan 56° 39°
- Feb 62° 42°
- Mar 68° 45°
- Apr 74° 48°
- May 82° 54°
- Jun 90° 59°
- Jul 95° 63°
- Aug 94° 62°
- Sep 89° 59°
- Oct 79° 52°
- Nov 66° 43°
- Dec 56° 39°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Modesto in September?
The normal high is 89°F and the normal low 59°F, for a daily mean of 73.9°F. September is 3.9°F cooler than August and 8.7°F warmer than October. September is the 4th warmest month of the year in Modesto 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 1.6°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 72°F and 76°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 4%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 92°F | 61°F | 1% | 1% |
| September 8 | 91°F | 60°F | 1% | 1% |
| September 15 | 90°F | 59°F | 2% | 1% |
| September 22 | 88°F | 58°F | 3% | 2% |
| September 30 | 85°F | 56°F | 4% | 2% |
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 | 61°F | 1% | 1% | 13 h |
| September 2 | 92°F | 61°F | 1% | 1% | 13 h |
| September 3 | 92°F | 61°F | 1% | 1% | 13 h |
| September 4 | 92°F | 60°F | 1% | 1% | 13 h |
| September 5 | 91°F | 60°F | 1% | 1% | 12 h 50 min |
| September 6 | 91°F | 60°F | 1% | 1% | 12 h 50 min |
| September 7 | 91°F | 60°F | 1% | 1% | 12 h 50 min |
| September 8 | 91°F | 60°F | 1% | 1% | 12 h 50 min |
| September 9 | 91°F | 60°F | 1% | 1% | 12 h 40 min |
| September 10 | 91°F | 60°F | 1% | 1% | 12 h 40 min |
| September 11 | 90°F | 60°F | 1% | 1% | 12 h 40 min |
| September 12 | 90°F | 59°F | 1% | 1% | 12 h 40 min |
| September 13 | 90°F | 59°F | 2% | 1% | 12 h 30 min |
| September 14 | 90°F | 59°F | 2% | 1% | 12 h 30 min |
| September 15 | 90°F | 59°F | 2% | 1% | 12 h 30 min |
| September 16 | 89°F | 59°F | 2% | 1% | 12 h 30 min |
| September 17 | 89°F | 59°F | 2% | 1% | 12 h 20 min |
| September 18 | 89°F | 58°F | 2% | 1% | 12 h 20 min |
| September 19 | 89°F | 58°F | 2% | 2% | 12 h 20 min |
| September 20 | 88°F | 58°F | 2% | 2% | 12 h 20 min |
| September 21 | 88°F | 58°F | 3% | 2% | 12 h 10 min |
| September 22 | 88°F | 58°F | 3% | 2% | 12 h 10 min |
| September 23 | 87°F | 57°F | 3% | 2% | 12 h 10 min |
| September 24 | 87°F | 57°F | 3% | 2% | 12 h 10 min |
| September 25 | 87°F | 57°F | 3% | 2% | 12 h 10 min |
| September 26 | 87°F | 57°F | 3% | 2% | 12 h |
| September 27 | 86°F | 57°F | 3% | 2% | 12 h |
| September 28 | 86°F | 56°F | 3% | 2% | 12 h |
| September 29 | 86°F | 56°F | 4% | 2% | 12 h |
| September 30 | 85°F | 56°F | 4% | 2% | 11 h 50 min |
- Normal high
- 89°FSeptember average
- Normal low
- 59°FSeptember average
- Precipitation
- 0.06 inmonth total
- Days with precipitation
- fewer than 10.01 inch or more
- Days at 90°F or more
- 15
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 30
- Days at 80°F or more
- 27
- Sunshine
- 96%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00023258; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Modesto in September?
On a given September day the chance of 0.01 inch or more is 2% on average, highest around September 30 (4%). In all, 0.06 in falls on 0 days of a normal September.
In a normal September in Modesto, 15 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00023258.
What are the records for September in Modesto?
The warmest September temperature on this station's record (since 1927) is 112°F, on September 6, 2022; the coldest is 40°F, on September 26, 1948. The wettest September brought 2.19 in (1983).
The September mean against the 1991-2020 normal of 73.9°F: 2021 74.0°F (+0.1), 2022 77.2°F (+3.3), 2023 71.5°F (−2.4), 2024 76.5°F (+2.5), 2025 76.0°F (+2.1), 2026 73.3°F (−0.6). 4 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 74.0°F | +0.1°F | 0.03 in |
| 2022 | 77.2°F | +3.3°F | 0.08 in |
| 2023 | 71.5°F | −2.4°F | 0.06 in |
| 2024 | 76.5°F | +2.5°F | 0.00 in |
| 2025 | 76.0°F | +2.1°F | 0.20 in |
| 2026 | 73.3°F | −0.6°F | 0.00 in |
Source: records: ACIS, station USW00023258; recent months: ACIS, station USW00023258. Records and recent months use complete months only.
How does September in Modesto 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; Modesto's is 89°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.