Weather in Boise, Idaho, United States in September
In an average September, Boise sees a daily high around 78°F and a low around 52°F, based on 1981–2026 of local climate records.
| Average high | 78°F |
|---|---|
| Typical high range | 65°F to 90°F |
| Average low | 52°F |
| Typical low range | 43°F to 61°F |
| Average daily precipitation | 0.00 in |
September records
The most extreme September on record for each metric, across 1981–2026. For rainfall, the wettest and driest are by total September accumulation.
High
Highest
104°F
2022-09-06
Lowest
50°F
1986-09-25
Low
Highest
73°F
1998-09-05
Lowest
30°F
1985-09-29
Feels-like
Highest
103°F
2022-09-07
Lowest
19°F
1985-09-29
Humidity
Highest
12.7 g/m³
2013-09-03
Lowest
1.5 g/m³
1999-09-29
Wind
Highest
33 mph
2020-09-07
Lowest
3 mph
1998-09-26
Precip
Wettest
2.80 in
1986
Driest
0.01 in
1987
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