Historical weather data, all-time temperature records, and monthly climate averages for Tri-Cities, WA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5 in Tri-Cities typically feels like spring has arrived, with average highs around 62° and lows of 37°. There's a 27% chance of rain, but snow is essentially off the table. The date has seen a 45-degree swing in its history — from a chilly 25° low in 2015 to a pleasant 70° high in 2009.
Tri-Cities plays in the extremes. The all-time high of 115° during the June 2021 heat dome is among the most intense readings ever recorded in the Pacific Northwest, while a brutal -19° in January 2004 shows this high desert city doesn't coast through winter. Remarkably, the wettest day on record was just 1.1" — this place is dry by almost any measure.
Tri-Cities runs hot and sunny for a long stretch, with highs climbing from 67° in April to a peak of around 95° in mid-July — prime time for outdoor plans. Winters are cold but brief, bottoming out near 40° in mid-January before the rapid spring warmup begins. If you're trying to avoid rain, almost any month works; even the wettest week of the year averages just 0.42".