SEATTLE — Widespread thunderstorms hit western Washington Wednesday evening.
A Severe Thunderstorm Watch for King County and southward counties into Oregon expired at 9 p.m. night.
Seattle-Tacoma International Airport issued a ground stop for arriving flights for several hours due to the thunderstorms. It was lifted at 9:30 p.m.
A home in Everett was reportedly struck by lightning just before 8:30 p.m., according to the Everett Fire Department.
Firefighters extinguished a fire on the roof and found the home’s electrical system had been comprised. No one was injured, the department said.
Though not as high as Tuesday’s temperatures, Wednesday was unseasonably warm with high temperatures in the 60s.
The NWS forecasted that an air mass above western Washington led to thunderstorms, hail, wind, cloud-to-ground lightning and periods of heavy rainfall.
The greatest concerns related to the weather system was lightning and the possibility of large hail.
There was a 2-4% chance of a tornado along the I-5 corridor, according to the weather service. No tornado activity was reported.
According to the National Oceanic and Atmospheric Administration (NOAA), thunderstorms need three “basic ingredients” to form, all of which will be present Wednesday in western Washington.
Moisture needs to be present, air needs to be unstable and rising, and something needs to nudge the air upward toward the clouds.
Higher than normal surface temperatures raise the warm air that’s lower to the ground up into the atmosphere, carrying water vapor that begins to cool as the air rises.
The air will continue to rise as long as it weighs less and stays warmer than the air around it, according to the NOAA.
As the water vapor condenses, the air and the water vapor form a cloud, which eventually rises into areas where the temperature is below freezing. The water particles will become particles of ice. When two ice particles collide, one particle can rip off “a little bit of ice” from the other one, and take with it some electric charge. As these collisions occur more frequently, large regions of electric charges build up to cause a bolt of lightning, which creates the sound we know as thunder.
