July 27, 2017

Drizzle Storm Hits Seattle: One Record Lost

A deepening marine layer this morning resulted in a period of very light drizzle, producing a trace (less than .01 inches) of precipitation at Seattle-Tacoma Airport.

As a result, we have lost the chance for a big record:  the first July or any month without any precipitation at Seattle-Tacoma Airport, a location with data back to 1948.

The visible satellite imagery this morning at 9 AM shows marine clouds over western WA.

And the Seattle Space Needle Panocam shows a very moist, drippy lower atmosphere.

The hourly observations shows the precipitation event (L- indicates very light rain and T means trace). Drizzle started at 6:42 AM and ended 7:29 AM).

Since we had only a trace of rain, we still might beat the big record--the record number of days in a row without measurable rain  (51 days).

Today, we are at day 40.  The latest European Center model ensemble forecast prediction for 24-h precipitation suggests we are on the edge for beating the record, particularly with a potential light event on July 31st when the ensemble mean reaches .012 inches.

Keep your fingers crossed.


  1. So jealous! Heavy clouds this morning, but no precip in Bellingham.

  2. I notice that you refer to Seattle precipitation but then use readings from SeaTac Airport, which is not in Seattle. An example is the prior post where you referred to lack of precipitation in Seattle, readers noted that there had been precipitation in Seattle, then you stated you were using really using readings from SeaTac, not Seattle.

    Perhaps if you clarified in your posts that you were reporting on SeaTac weather there would be less confusion.

    (Not that it matters for me. Weather in Olympia matches neither that of Seattle nor SeaTac.)

  3. Lovely, lovely, such a lovely break from the hot sun. If only temporarily.
    I find myself already looking forward to fall.

  4. Coming at you with a complete thread drift from what post i am commenting on, so apologies here but it is a burning question for me.

    Simply, is there a guess as to what the weather might look like in the PNW on August 21, for this semi local once in a lifetime solar eclipse for us?

    Lucky ducks in Oregon will get totality, but we wont do bad... depending on the weather/cloud cover.

    Im guessing this dry spell will magically go away with a freak monsoon on the 21st 8-P

  5. The NWS discussion had an intriguing tidbit, linking our stable high pressure to strong monsoons in the southwest. I'm curious what that linkage might be.

  6. Please, please, please bring on the rain!!!!!! We need it very badly. SOOOO sick of this sunny and dry weather. If you disagree, I suggest you move to Eastern WA or go to the many other states that are dry and hot. The rain and clouds are what make the Pacific NW a place I want to live. -Praying for rain-

  7. Well, that's what Seattle is famous for.

  8. oh come on. the rain is a given here. this is what is called "summer". it happens every year. looks like we're in the 90s next week....YES!!! bring it on.

  9. Seattle may have received a trace, but Whidbey Island sure didn't. Today is day #50 without rain here on our farm in Langley. The rain shadow is great most times of the year, but sometimes its a problem. The trees are incredibly stressed right now. Here's hoping for a mid August low pressure system.

  10. We had 0.07 inch in our rain gauge in Bellevue at the end of the day. I had some outdoor work to do out east of Chateau Ste. Michelle, where we had less than 0.01 fall there.

  11. Coyote, it's too early to have anything resembling an accurate forecast for sky conditions on the morning of 8/21. I mean, look at what happened with the drizzly marine push that was stronger than forecasted.

    Reading your post makes me concerned that you're considering seeing the eclipse from Seattle, rather than going to the path of totality. Let me make a personal appeal for you to reconsider.

    The difference between a total solar eclipse and a partial solar eclipse is quite literally night and day. Until the last morsel of solar photosphere is obscured, you don't get the world-stopping drama. What you get instead is a sad little crescent Sun at maximum eclipse, which I will tell you is less than 5% as awesome as seeing the chromosphere, prominences, and the wispy corona.


    People go to the ends of the Earth to see total solar eclipses. They do not do this for partial or annular eclipses. A total solar eclipse is coming within 250 miles of your house; the question is whether you'll brave the crowds and a little hassle to go see the one that almost comes to your doorstep.

  12. Interesting, about Whidbey. Because rural Port Townsend has had several trace precipitation events. All have been very wet fog, so I assume quite localized.......

    IMHO.. perfect summer, marine layer in the AM, sun, then cooling ocean breeze like clockwork ever afternoon. 50 to 70 degrees, dry and cool.. day after day. I am not one to complain about a short break in the relentless onslaught of storms we endure 9 months out of the year.

  13. The Weather Channel has gone crazy! Why is it forecasting 110 degrees in Portland on Thursday?

  14. It would be interesting for you to comment about the projections for record heat in the Portland metro area this coming weeks. The Weather Channel has predicted temps as high as 110(!) on Thursday. What is the scenario for this happening?

  15. @Dan,

    I would love to go south into Oregon to catch it, but a contractual work schedule on that day will not let me. I am going to do my best and try to find a way to go, but I don't know yet.

  16. @ Organic Farmer

    Definitely localized. We see major differences in drizzle events on South Whidbey Island depending on if your south of HWY 525 or north of it. The local topography seems to play a role in keeping Langley and its surroundings drier than the Useless Bay and Possession Point areas. We also just barely miss many convergence zone events by only a mile or two.


Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

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