It was a weird event. Storms fired along a Pacific cold front with T/dT spreads around 62/55. Simply put it was an atmospheric river which attacked the coast at the right angle, after a few days of persistent warm SSW flow and with a whole winter's worth of ground moisture.
We've had a few garden variety postfrontal thunderstorms in Seattle this spring. Around average. Could get some more cold core stuff if the long range is to be trusted.
I responded to this yesterday I believe, but from what I read it was cold core...as almost all west side PNW tornadoes are. Temps were in the 50s when it occurred.
Interesting, I always thought that April 1972 tornado was cold core since it was in April. Figured it was a showers and sun breaks type of day with intense showers and hail, etc. Speaking of that, where were those types of cold core days in early Spring this year? I really missed them. Seems like we either just had Pacific fronts or Tim-like weather this year.