Boise weather in September
September in Boise averages 80°F by day and 53°F at night, with 0.4 inches of precipitation. It is the 4th-warmest and 10th-wettest month of the year here.
- Average high
- 80°F-11° vs August
- Average low
- 53°F0 nights below freezing
- Precipitation
- 0.4 in1 days with 0.1 in. or more
- Snow
- 0.0 in5 days at 90°F+
Is September a good time to visit Boise?
Yes. September is one of the most comfortable months in Boise by our rule (highs of 62 to 86°F, lows of 42°F or more and under 4.5 inches of precipitation). The most comfortable months overall are May to June and September.
On September 15 the sun rises at 7:24 am and sets at 7:54 pm, giving 12h 30m of daylight. Daylight all year.
What to pack for Boise in September
- Summer clothes, with a light layer for air conditioning
Based on 30-year averages, not a forecast. Check the forecast a few days before you go.
September nearby
| City | Distance | High | Low | Precip. |
|---|---|---|---|---|
| Boise | 80°F | 53°F | 0.4 in | |
| Meridian, ID | 8 mi | 80°F | 53°F | 0.4 in |
| Nampa, ID | 18 mi | 81°F | 47°F | 0.4 in |
| Caldwell, ID | 26 mi | 81°F | 47°F | 0.4 in |
| Kennewick, WA | 229 mi | 81°F | 48°F | 0.3 in |
| Pasco, WA | 231 mi | 81°F | 48°F | 0.3 in |
| Missoula, MT | 251 mi | 73°F | 42°F | 1.0 in |
Frequently asked questions
What is the weather like in Boise in September?
In September, Boise averages a high of 80°F and a low of 53°F, with 0.4 inches of precipitation (NOAA 1991-2020 normals).
Is September a good time to visit Boise?
Yes. September is one of Boise's most comfortable months by our rule: highs between 62°F and 86°F, lows of 42°F or more and modest rain.
Does it snow in Boise in September?
Rarely. The September snowfall normal is under half an inch.
Before and after: Boise in August and Boise in October. All twelve months: Boise weather by month.
NOAA NCEI 1991-2020 climate normals, station Boise Air Terminal, ID, 2.3 miles from the city center.