Spring tends to be the peak for tornadoes in Washington with fall as a secondary time period. Washington averages close to two tornadoes per year - not in the league as Tornado Alley in the middle of the U.S. but tornadoes can be quite dangerous here.
What is a tornado? It is a rapidly rotating column of air in contact with the ground. A waterspout is the same rapidly rotating column of air, yet in contact with a body of water such as Puget Sound. A funnel cloud is a rotating column of air not in contact with the ground.
The key word here is rotating. There are many false reports of funnel clouds. Remember tornadoes, waterspouts and funnel clouds are almost always associated with thunderstorms. There are a lot of look-alike clouds. Look for rotation.
Last year, Washington had two tornadoes and one waterspout. On March 21, a very weak tornado touched down briefly near Hockinson in Clark county. The other tornado struck on September 30 near Frederickson in Pierce County and was on the ground for about five minutes. A few days later on October 2, a waterspout was noted off the coast of Westport.
Most Washington tornadoes tend to be weak and short-lived - EF0 or EF1 in strength and down and up in less than two minutes. EF0 and EF1 tornadoes have winds of about 110 mph or less. In 1997, the state had a record 14 tornadoes in the year and all were EF0 or EF1 events.
Yet the state has had a number of EF2 tornadoes with winds up to 135 mph and three EF3 tornadoes. One EF3 tornado tracked through south King County in September of 1969. The other two occurred on the same day - April 5, 1972 in Vancouver and outside of Davenport west of Spokane. Washington led the nation in tornado deaths in 1972 as a result of the Vancouver tornado that plowed through a grocery store, bowling house and a school, killing six and injuring over 200.
Tornadoes are rare and usually short-lived in Washington. Yet if you see a tornado or get a tornado warning, move indoors to a basement or lower floor interior room such as a closet. Then report the event to the National Weather Service in Seattle at 206-526-6095 or via NWS Seattle social media. If you are on the water and see a waterspout, head in the opposite direction and get into protected waters such as a harbor or port.
You might also want to read: