Tri-Cities to sizzle under heat wave in coming days. Plus outlook for July 4

The Tri-Cities is expected to swelter under its second heat wave of the year with 100+ temperatures Monday and Tuesday.

A heat advisory has been issued by the National Weather Service for most of Central and Eastern Washington, including the Tri-Cities, extending into parts of Oregon and Idaho.

In the Tri-Cities the heat advisory starts at 9 a.m. Monday and is set to expire at 9 p.m. Tuesday.

A high of 100 is forecast for Monday, heating up to 103 on Tuesday.

Nighttime lows also will be substantially warmer than usual at a forecast 67 on Monday night and 70 on Tuesday night.

Normal highs for the first day of July in the Tri-Cities are 88 and normal lows are 54, according to the weather service.

High temperatures will cool some starting Wednesday, with a high forecast at 98, but then high temperatures should be in the low to mid 90s through the weekend.

Tri-Cities residents can expect a sunny July 4 with a high of about 93, according to the weather service.’

The hottest weather of the year so far in the Tri-Cities was on June 9, with a high of 103. The high was 100 the next day. But nighttime temperatures were a little cooler then than expected on Monday and Tuesday.

The forecast low of 70 for Tuesday night is the warmest of the year so far.

This story was originally published June 29, 2025 at 4:44 PM.