Nampa weather in September: Nampa, Idaho: normal highs, lows, rain and records for September
Nampa in September has a normal high of 81°F and a normal low of 47°F, a daily mean of 64°F, falling from 86°F on the 1st to 75°F by the 30th. Measurable precipitation falls on 3 days in a normal September, 0.36 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 27°C and low of 8°C, 9 mm of precipitation in September.
- NOAA stationNampa Sugar Factory
- Station IDUSC00106305
- Location43.60°N 116.58°W
- Elevation2,470 ft (753 m)
- Population117,350
- Jan 40° 23°
- Feb 47° 26°
- Mar 57° 32°
- Apr 65° 36°
- May 74° 44°
- Jun 83° 51°
- Jul 93° 57°
- Aug 92° 56°
- Sep 81° 47°
- Oct 67° 37°
- Nov 51° 28°
- Dec 40° 23°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Nampa in September?
The normal high is 81°F and the normal low 47°F, for a daily mean of 63.8°F. September is 9.8°F cooler than August and 12.3°F warmer than October. September is the 4th warmest month of the year in Nampa and the 10th wettest. Across the month the normal high falls 11°F, from 86°F on September 1 to 75°F on September 30. From one year to the next September's mean temperature typically moves about 2.1°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 62°F and 66°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 13%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 86°F | 51°F | 7% | 3% |
| September 8 | 84°F | 49°F | 8% | 3% |
| September 15 | 81°F | 47°F | 9% | 3% |
| September 22 | 79°F | 45°F | 11% | 4% |
| September 30 | 75°F | 42°F | 13% | 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 | 86°F | 51°F | 7% | 3% | 13 h 20 min |
| September 2 | 86°F | 51°F | 7% | 3% | 13 h 10 min |
| September 3 | 86°F | 50°F | 7% | 3% | 13 h 10 min |
| September 4 | 85°F | 50°F | 8% | 3% | 13 h 10 min |
| September 5 | 85°F | 50°F | 8% | 3% | 13 h |
| September 6 | 85°F | 50°F | 8% | 3% | 13 h |
| September 7 | 84°F | 49°F | 8% | 3% | 13 h |
| September 8 | 84°F | 49°F | 8% | 3% | 13 h |
| September 9 | 84°F | 49°F | 8% | 3% | 12 h 50 min |
| September 10 | 83°F | 48°F | 9% | 3% | 12 h 50 min |
| September 11 | 83°F | 48°F | 9% | 3% | 12 h 50 min |
| September 12 | 83°F | 48°F | 9% | 3% | 12 h 40 min |
| September 13 | 82°F | 47°F | 9% | 3% | 12 h 40 min |
| September 14 | 82°F | 47°F | 9% | 3% | 12 h 40 min |
| September 15 | 81°F | 47°F | 9% | 3% | 12 h 30 min |
| September 16 | 81°F | 46°F | 10% | 4% | 12 h 30 min |
| September 17 | 81°F | 46°F | 10% | 4% | 12 h 30 min |
| September 18 | 80°F | 46°F | 10% | 4% | 12 h 30 min |
| September 19 | 80°F | 46°F | 10% | 4% | 12 h 20 min |
| September 20 | 79°F | 45°F | 10% | 4% | 12 h 20 min |
| September 21 | 79°F | 45°F | 11% | 4% | 12 h 20 min |
| September 22 | 79°F | 45°F | 11% | 4% | 12 h 10 min |
| September 23 | 78°F | 44°F | 11% | 4% | 12 h 10 min |
| September 24 | 78°F | 44°F | 11% | 4% | 12 h 10 min |
| September 25 | 77°F | 44°F | 11% | 5% | 12 h 10 min |
| September 26 | 77°F | 43°F | 12% | 5% | 12 h |
| September 27 | 76°F | 43°F | 12% | 5% | 12 h |
| September 28 | 76°F | 43°F | 12% | 5% | 12 h |
| September 29 | 75°F | 42°F | 12% | 5% | 11 h 50 min |
| September 30 | 75°F | 42°F | 13% | 5% | 11 h 50 min |
- Normal high
- 81°FSeptember average
- Normal low
- 47°FSeptember average
- Precipitation
- 0.36 inmonth total
- Days with precipitation
- 30.01 inch or more
- Days at 90°F or more
- 6
- Daylight
- 13 h 20 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 27
- Days at 80°F or more
- 18
- Sunshine
- 89%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00106305; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Nampa in September?
On a given September day the chance of 0.01 inch or more is 10% on average, highest around September 30 (13%). In all, 0.36 in falls on 3 days of a normal September.
In a normal September in Nampa, 6 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00106305.
What are the records for September in Nampa?
The warmest September temperature on this station's record (since 1976) is 101°F, on September 5, 1998; the coldest is 28°F, on September 25, 1984. The wettest September brought 2.87 in (1980).
Source: records: ACIS, station USC00106305. Records and recent months use complete months only.
How does September in Nampa compare across Idaho?
Across the 85 places PlainClimate covers in Idaho, September normal highs run from 59°F in Mullan to 86°F in Glenns Ferry; Nampa's is 81°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.