Thermograph

How unusual is the weather? Graded against ~45 years of local climate history.

Weather in Boise in September

In an average September, Boise sees a daily high around 81°F and a low around 53°F, based on 1980–2026 of local climate records.

Average high81°F
Typical high range68°F to 92°F
Average low53°F
Typical low range45°F to 62°F
Average daily precipitation0.00 in

September records

The most extreme September on record for each metric, across 1980–2026. For rainfall, the wettest and driest are by total September accumulation.

High

Highest 104°F 2022-09-03
Lowest 53°F 1986-09-27

Low

Highest 74°F 1998-09-05
Lowest 31°F 1984-09-25

Feels-like

Highest 109°F 2000-09-14
Lowest 22°F 1984-09-25

Humidity

Highest 14.3 g/m³ 1980-09-10
Lowest 2.9 g/m³ 1993-09-21

Wind

Highest 28 mph 2020-09-07
Lowest 3 mph 2010-09-13

Gust

Highest 50 mph 2020-09-08
Lowest 10 mph 2015-09-30

Precip

Wettest 2.36 in 1985
Driest 0.00 in 1999

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