Renton weather in September: Renton, Washington: normal highs, lows, rain and records for September
Renton in September has a normal high of 72°F and a normal low of 53°F, a daily mean of 62°F, falling from 76°F on the 1st to 67°F by the 30th. Measurable precipitation falls on 9 days in a normal September, 1.53 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 22°C and low of 12°C, 39 mm of precipitation in September.
- NOAA stationRenton Municipal Airport
- Station IDUSW00094248
- Location47.49°N 122.21°W
- Elevation29 ft (9 m)
- From the center1 miles
- Population105,543
- Jan 48° 37°
- Feb 50° 37°
- Mar 55° 40°
- Apr 60° 43°
- May 66° 49°
- Jun 71° 54°
- Jul 77° 58°
- Aug 78° 57°
- Sep 72° 53°
- Oct 61° 46°
- Nov 52° 40°
- Dec 47° 37°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Renton in September?
The normal high is 72°F and the normal low 53°F, for a daily mean of 62.4°F. September is 5.1°F cooler than August and 8.7°F warmer than October. September is the 3rd warmest month of the year in Renton and the 9th wettest. Across the month the normal high falls 9°F, from 76°F on September 1 to 67°F on September 30. From one year to the next September's mean temperature typically moves about 1.7°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 61°F and 64°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 38%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 76°F | 56°F | 22% | 11% |
| September 8 | 74°F | 55°F | 26% | 12% |
| September 15 | 72°F | 53°F | 30% | 14% |
| September 22 | 70°F | 52°F | 34% | 16% |
| September 30 | 67°F | 50°F | 38% | 19% |
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 | 76°F | 56°F | 22% | 11% | 13 h 30 min |
| September 2 | 75°F | 55°F | 23% | 11% | 13 h 20 min |
| September 3 | 75°F | 55°F | 23% | 11% | 13 h 20 min |
| September 4 | 75°F | 55°F | 24% | 11% | 13 h 20 min |
| September 5 | 75°F | 55°F | 24% | 12% | 13 h 10 min |
| September 6 | 74°F | 55°F | 25% | 12% | 13 h 10 min |
| September 7 | 74°F | 55°F | 25% | 12% | 13 h 10 min |
| September 8 | 74°F | 55°F | 26% | 12% | 13 h |
| September 9 | 74°F | 54°F | 26% | 13% | 13 h |
| September 10 | 74°F | 54°F | 27% | 13% | 13 h |
| September 11 | 73°F | 54°F | 27% | 13% | 12 h 50 min |
| September 12 | 73°F | 54°F | 28% | 13% | 12 h 50 min |
| September 13 | 73°F | 54°F | 29% | 14% | 12 h 50 min |
| September 14 | 72°F | 54°F | 29% | 14% | 12 h 40 min |
| September 15 | 72°F | 53°F | 30% | 14% | 12 h 40 min |
| September 16 | 72°F | 53°F | 30% | 15% | 12 h 40 min |
| September 17 | 71°F | 53°F | 31% | 15% | 12 h 30 min |
| September 18 | 71°F | 53°F | 32% | 15% | 12 h 30 min |
| September 19 | 71°F | 53°F | 32% | 15% | 12 h 30 min |
| September 20 | 70°F | 52°F | 33% | 16% | 12 h 20 min |
| September 21 | 70°F | 52°F | 33% | 16% | 12 h 20 min |
| September 22 | 70°F | 52°F | 34% | 16% | 12 h 20 min |
| September 23 | 69°F | 52°F | 34% | 17% | 12 h 10 min |
| September 24 | 69°F | 52°F | 35% | 17% | 12 h 10 min |
| September 25 | 69°F | 51°F | 35% | 17% | 12 h 10 min |
| September 26 | 68°F | 51°F | 36% | 18% | 12 h |
| September 27 | 68°F | 51°F | 36% | 18% | 12 h |
| September 28 | 68°F | 51°F | 37% | 18% | 12 h |
| September 29 | 67°F | 51°F | 37% | 19% | 11 h 50 min |
| September 30 | 67°F | 50°F | 38% | 19% | 11 h 50 min |
- Normal high
- 72°FSeptember average
- Normal low
- 53°FSeptember average
- Precipitation
- 1.53 inmonth total
- Days with precipitation
- 90.01 inch or more
- Daylight
- 13 h 30 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 17
- Days at 80°F or more
- 4
- Sunshine
- 74%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00094248; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Renton in September?
On a given September day the chance of 0.01 inch or more is 30% on average, highest around September 30 (38%). In all, 1.53 in falls on 9 days of a normal September.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00094248.
What are the records for September in Renton?
The warmest September temperature on this station's record (since 1998) is 91°F, on September 10, 2020; the coldest is 40°F, on September 23, 2000. The wettest September brought 5.89 in (2013).
The September mean against the 1991-2020 normal of 62.4°F: 2021 62.9°F (+0.5), 2022 65.5°F (+3.1), 2023 63.3°F (+0.9), 2025 65.8°F (+3.4), 2026 60.8°F (−1.6). 4 of 5 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 62.9°F | +0.5°F | 1.92 in |
| 2022 | 65.5°F | +3.1°F | 0.10 in |
| 2023 | 63.3°F | +0.9°F | 1.70 in |
| 2025 | 65.8°F | +3.4°F | – |
| 2026 | 60.8°F | −1.6°F | 0.93 in |
Source: records: ACIS, station USW00094248; recent months: ACIS, station USW00094248. Records and recent months use complete months only.
How does September in Renton compare across Washington?
Across the 96 places PlainClimate covers in Washington, September normal highs run from 66°F in Coupeville to 81°F in Pasco; Renton's is 72°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.