May 20, 2009


Sometimes the weather gets downright scintillating around here...and last night was a good example. An intense convergence zone formed north of Seattle, with heavy rain and even some small hail/graupel. My house was inundated, with 1.25 inches over the day. The strong convection in the convergence zone produced about a half-dozen lightning strikes with rumbling thunder. Thunderstorms here are generally wimpy in the lightning department...often with 1-2 strokes for the entire event.

My profession has sensors for lightning strikes. Ever listen to the AM radio during thunderstorms and hear intermittent static...that can be caused by lightning. With the proper receivers and electronics one can determine the lightning stroke location and intensity. Below you see lightning graphics from our regional system for the half hours starting at 7:30 and 8 PM Tuesday night. You can see the Seattle strokes.

One of the lightning bolts hit a power pole in Laurelhurst near the home of one of my colleagues. They lost power as the transformer blew up and pole ignited. Took the Seattle fire department two visits to get it out. With bears on the lose and lightning burning up power poles, this city is starting to get fun.

Just some reminders:

We need supporters of the coastal radar acquisition at the community meeting on Thursday, May 28 at 10:30 AM sponsored by Senator Maria Cantwell (NOAA Bldg 9 near Seattle Magnusson Park. The head of the National Weather Service will be there and we need him to know where we stand. You have to RSVP (

I will be giving a talk on a consumer's guide to NW weather at Barnes and Noble, Univ. Village, at 7:30 PM on Friday.


  1. Tue was pretty showery with a few sun breaks. And though I saw no lightning here at our place atop Hollywood hill, Woodinville.... I heard a few rumbles of close by thunder Tue evening. And with Tue`s showers, plus the active CZ....I picked up 0.78" of rain during the course of the day. So a pretty wet day!

  2. Ahhh, thunder and lightning! The only thing making me jealous of the Puget Sound Convergence Zone. I miss the big booms and rolls of New Jersey and the Sharp cracks and crackles of Chicago. Is there a study of the different types of thunder/lightning?

  3. In Crown Hill we had a very nice double rainbow off to the east. The rain stopped quickly and we had blue sky move in. All the rain soaked trees were lit up by the sun. Very nice. We heard two lightning strikes. I get excited after one because that's all we ever seem to get.

  4. Cliff - I know you like to talk about the June gloom, and I've lived here long enough to experience it every single year, but it looks like we are set up for a very summer-like pattern here to end May and maybe start out June - a stretch of high pressure dominated days w/o rain - with no end in sight in the 10 day forecast. I really can't remember anything like this in late May.

  5. C.P.O.:
    We`ve actually had some warm weather in late May in recent years, 2005 and 2007 to be exact. ( Also, don`t forget that it was 90 last year on May 17th.)In the last 25 years or so,there actually have been more episodes of hot weather around Memorial Day than the 4th of July!

  6. you guys were so lucky!!! This time of year makes me homesick for pullman... this is when the t-storms get started.

  7. I've come to expect some hot days in late May and cooler, wetter weather in June. Enjoy while it lasts!


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