This story was originally published on MyNorthwest.com.
The primary thunderstorm season in western Washington usually kicks off in March. Thunderstorms can occur throughout the year, but springtime is prime time, while fall has another rise in thunderstorm activity.
There is a good reason why this region’s thunderstorm season gets rolling in March. Thanks to longer days as spring unfolds, temperatures near the surface are warmer than during winter.
Yet, cooler air aloft continues to move onshore from the Gulf of Alaska, creating an unstable air mass allowing warmer air near the surface to rise more easily and generate storms — much like boiling water on your stove but on a grand scale.
The region’s mountainous terrain and the Puget Sound Convergence Zone phenomenon also provide lift to help hoist that warmer air aloft.
Average number of thunderstorms in western Washington
Western Washington averages only about 10 thunderstorms per year. This average is in contrast with central Florida, which gets over 100 thunderstorms annually. The Orlando area theme parks have some of the world’s best lightning detection systems and safety plans to help keep guests and staff out of harm’s way.
From the Rockies eastward, people are rather lightning proficient — heading indoors when a thunderstorm approaches. Since Western Washington does not get many thunderstorms, some people are caught unaware and outdoors when lightning strikes.
Lightning safety
This region’s thunderstorms are usually short-lived, less than 30 minutes. If a cold rain or hail shower approaches, that is a clue that it could produce lightning.
Take action like heading indoors or getting into a vehicle. Avoid tall targets like trees. Lightning likes to strike tall objects, and that is where many lightning injuries and fatalities occur.
Fortunately, Washington has not had a lightning fatality since 1996. Let’s keep it that way. Remember the phrase — when thunder roars, go indoors.