Ames weather in September: Ames, Iowa: normal highs, lows, rain and records for September
Ames in September has a normal high of 76°F and a normal low of 51°F, a daily mean of 63°F, falling from 80°F on the 1st to 71°F by the 30th. Measurable precipitation falls on 10 days in a normal September, 3.31 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 24°C and low of 11°C, 84 mm of precipitation in September.
- NOAA stationAmes Municipal Airport
- Station IDUSW00094989
- Location41.99°N 93.62°W
- Elevation930 ft (284 m)
- From the center2 miles
- Population69,026
- Jan 29° 11°
- Feb 33° 15°
- Mar 47° 27°
- Apr 61° 38°
- May 72° 50°
- Jun 81° 60°
- Jul 84° 63°
- Aug 82° 60°
- Sep 76° 51°
- Oct 63° 39°
- Nov 47° 27°
- Dec 34° 17°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Ames in September?
The normal high is 76°F and the normal low 51°F, for a daily mean of 63.4°F. September is 7.6°F cooler than August and 12.5°F warmer than October. September is the 4th warmest month of the year in Ames and the 6th wettest. Across the month the normal high falls 9°F, from 80°F on September 1 to 71°F on September 30. From one year to the next September's mean temperature typically moves about 3.1°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 60°F and 67°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 36%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 80°F | 56°F | 36% | 19% |
| September 8 | 78°F | 54°F | 35% | 19% |
| September 15 | 76°F | 51°F | 33% | 18% |
| September 22 | 74°F | 49°F | 32% | 18% |
| September 30 | 71°F | 45°F | 31% | 18% |
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 | 80°F | 56°F | 36% | 19% | 13 h 10 min |
| September 2 | 80°F | 56°F | 36% | 19% | 13 h 10 min |
| September 3 | 79°F | 56°F | 36% | 19% | 13 h 10 min |
| September 4 | 79°F | 55°F | 35% | 19% | 13 h |
| September 5 | 79°F | 55°F | 35% | 19% | 13 h |
| September 6 | 79°F | 55°F | 35% | 19% | 13 h |
| September 7 | 79°F | 54°F | 35% | 19% | 13 h |
| September 8 | 78°F | 54°F | 35% | 19% | 12 h 50 min |
| September 9 | 78°F | 53°F | 34% | 19% | 12 h 50 min |
| September 10 | 78°F | 53°F | 34% | 19% | 12 h 50 min |
| September 11 | 78°F | 53°F | 34% | 19% | 12 h 40 min |
| September 12 | 77°F | 52°F | 34% | 19% | 12 h 40 min |
| September 13 | 77°F | 52°F | 33% | 18% | 12 h 40 min |
| September 14 | 77°F | 52°F | 33% | 18% | 12 h 40 min |
| September 15 | 76°F | 51°F | 33% | 18% | 12 h 30 min |
| September 16 | 76°F | 51°F | 33% | 18% | 12 h 30 min |
| September 17 | 76°F | 50°F | 33% | 19% | 12 h 30 min |
| September 18 | 76°F | 50°F | 33% | 19% | 12 h 20 min |
| September 19 | 75°F | 50°F | 33% | 18% | 12 h 20 min |
| September 20 | 75°F | 49°F | 33% | 18% | 12 h 20 min |
| September 21 | 74°F | 49°F | 32% | 18% | 12 h 20 min |
| September 22 | 74°F | 49°F | 32% | 18% | 12 h 10 min |
| September 23 | 74°F | 48°F | 32% | 18% | 12 h 10 min |
| September 24 | 73°F | 48°F | 32% | 18% | 12 h 10 min |
| September 25 | 73°F | 47°F | 32% | 18% | 12 h 10 min |
| September 26 | 73°F | 47°F | 32% | 18% | 12 h |
| September 27 | 72°F | 47°F | 31% | 18% | 12 h |
| September 28 | 72°F | 46°F | 31% | 18% | 12 h |
| September 29 | 71°F | 46°F | 31% | 18% | 11 h 50 min |
| September 30 | 71°F | 45°F | 31% | 18% | 11 h 50 min |
- Normal high
- 76°FSeptember average
- Normal low
- 51°FSeptember average
- Precipitation
- 3.31 inmonth total
- Days with precipitation
- 100.01 inch or more
- Days at 90°F or more
- 2
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 24
- Days at 80°F or more
- 12
- Sunshine
- 80%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00094989; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Ames in September?
On a given September day the chance of 0.01 inch or more is 33% on average, highest around September 1 (36%). In all, 3.31 in falls on 10 days of a normal September, 1 of them with an inch or more.
In a normal September in Ames, 2 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00094989.
What are the records for September in Ames?
The warmest September temperature on this station's record (since 1996) is 99°F, on September 11, 2000; the coldest is 27°F, on September 30, 2003. The wettest September brought 8.94 in (2016).
The September mean against the 1991-2020 normal of 63.4°F: 2021 67.5°F (+4.1), 2022 65.3°F (+1.9), 2023 68.1°F (+4.7), 2024 67.4°F (+4.0), 2025 67.7°F (+4.3), 2026 68.3°F (+4.9). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 67.5°F | +4.1°F | 2.43 in |
| 2022 | 65.3°F | +1.9°F | 2.19 in |
| 2023 | 68.1°F | +4.7°F | 2.51 in |
| 2024 | 67.4°F | +4.0°F | 0.83 in |
| 2025 | 67.7°F | +4.3°F | 0.52 in |
| 2026 | 68.3°F | +4.9°F | 6.45 in |
Source: records: ACIS, station USW00094989; recent months: ACIS, station USW00094989. Records and recent months use complete months only.
How does September in Ames compare across Iowa?
Across the 132 places PlainClimate covers in Iowa, September normal highs run from 71°F in Northwood to 79°F in Glenwood; Ames's is 76°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.