WASHINGTON — The warm, muggy conditions remain for Western Washington through tonight and into Wednesday morning. We are likely to have more dense fog around the interior and morning travel will be murky in these areas. The fog will break up in the mid-late morning hours.
Once the fog and low cloud clear, we’ll see temperatures on the rise again. There is the chance for an isolated shower or storm across the Olympic Peninsula and west of Puget Sound in the morning, but I expect the heavy weather to hold off until late afternoon.
With warm weather and humidity in place, a potent area of low pressure with cold air aloft is on a collision course with the summerlike airmass in place -- ingredients for strong storms look to be there in abundance for Wednesday late afternoon into Wednesday night.
Thunderstorms could pop along the Cascade crest in the afternoon hours, but as the disturbance moves north, thunderstorms will fire down in Oregon and southern Washington through the mid-afternoon hours, moving north quickly.
Pinpoint Futuretrack has strong storms affecting the South Sound, including Lewis, Thurston, Mason counties up to Tacoma from 4-6 p.m. with storms moving north impacting the Seattle area by 7 p.m., Everett and the North Sound by 8 p.m. and Bellingham and the Canadian border regions by 9-10 p.m. The timing is approximate and there will be thunderstorm activity possible outside of these “prime times” for thunderstorms moving north.
Large, damaging hail is the greatest threat from these storms with hail sizes possibly exceeding official Severe Thunderstorm criteria, which is wind gusts of 58 mph or greater and/or hail of one inch in diameter or larger. A Severe Thunderstorm Watch is possible late Wednesday, meaning that the conditions for severe thunderstorms exist. Seattle has never been in a Severe Thunderstorm Watch area, and only parts of the South Sound were in such a watch area back in May 4, 2017.
The @NWSSPC has upgraded parts of Western WA to a "slight" or 2 out of 5 risk for severe weather Wednesday late afternoon and evening. Primary risk is large, damaging hail greater than 1" in diameter with a lower risk of damaging wind and tornadoes. More on @KIRO7Seattle at noon.… https://t.co/ltJ10WTMvd
— Morgan Palmer (@MorganKIRO7) March 25, 2025
The last time we had a verified report of hail of one inch or larger was in Lewis County in 2017. This could be more widespread Wednesday late afternoon and evening! I recommend outdoor events after 4 p.m. be postponed to another day, and vehicles be parked under substantial cover, if possible. Hail of one inch or larger can damage vehicles, roofs, and trees, and be very dangerous to anyone outside — pets too!
The tornado threat is low in the lowlands but overall a greater chance than we typically see. Storms that do begin rotating will need to be watched closely for the chance for an isolated tornado. Of particular interest will be any rotating storms nearer the Cascades, as wind currents and rotation could be “tightened up” as storms enter foothill and mountain locations.
Lightning will be very frequent, and these storms could rival the electrical activity we experienced last August 17, when more than 3,000 lightning strikes were detected in Western Washington. This lightning is very dangerous.
Torrential rainfall will occur with these storms as well, posing a risk for drivers.
Thunderstorms will be moving northward at a rapid clip, so it will be important to keep abreast of conditions using the KIRO 7 Pinpoint Weather App. It might appear calm one minute, but then storms will quickly move in.
Storms look to clear the region by early Thursday morning as colder air moves into the area. We’ll be back in the 50s for highs with rain showers Thursday through Friday. There is a slight chance of an isolated, non-severe thunderstorm Thursday afternoon.
©2025 Cox Media Group
