Thermograph

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

Weather in Tri-Cities in September

In an average September, Tri-Cities sees a daily high around 83°F and a low around 54°F, based on 1980–2026 of local climate records.

Average high83°F
Typical high range72°F to 93°F
Average low54°F
Typical low range47°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 105°F 2022-09-03
Lowest 50°F 2019-09-29

Low

Highest 73°F 2019-09-06
Lowest 33°F 1985-09-29

Feels-like

Highest 118°F 2025-09-04
Lowest 24°F 2000-09-23

Humidity

Highest 14.8 g/m³ 2023-09-01
Lowest 3.2 g/m³ 1985-09-28

Wind

Highest 25 mph 2020-09-07
Lowest 3 mph 2017-09-26

Gust

Highest 49 mph 2020-09-07
Lowest 9 mph 2025-09-28

Precip

Wettest 1.51 in 1985
Driest 0.00 in 1991

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