The ingredients will be in place for a major thunderstorm event later this afternoon and tonight over western Washington.
Let me show you the latest high-resolution model forecasts from the NOAA/NWS HRRR model. The images below are forecast maps of simulated maximum radar reflectivity in a vertical column. Higher values are associated with more intense precipitation.
As 6 PM, very high values (oranges and reds) are predicted over western Oregon. Such high values are associated with thunderstorms.
Moving ahead to 9 PM, the storms in Puget Sound and over the southern WA Cascades will be crazy strong.
And these powerful thunderstorms will move northward at 11 PM, hitting NW Washington very hard.
Can we believe this forecast? The UW high resolution modeling system, which includes an ensemble of many forecasts, is going for a similar (be a bit more tame) wind event (time increases to the right). This is from the Seattle WindWatch webpage.
Finally, let me shown you the situation at 2:30 PM. The latest weather radar shows intense thunderstorms moving northward over the southern Willamette Valley. My god...this looks like Oklahoma.
And the lightning strike map at 2:20 PM shows massive amounts of lightning associated with these radar echoes.
Make sure you are ready for power outages and skip the kite flying. Enjoy.
How can such an event occur over western Washington? I will reveal the secrets in my next blog.
Don't do this tonight
Thanks Cliff. I suppose that Aurora watching will be a moot point now.
ReplyDeleteDo you think this might be as strong as the Sept 7th major thunderstorm that hit Puget Sound from the south, with major rains and I think wind, but countless lightning strikes with many of them ground to cloud strikes.
ReplyDeleteI lost power around 8:15pm that evening. Was at the computer when I heard a KABOOM, then a flash, lights etc go out. A pocket of us around a couple of blocks lost power due to a substation hit from a strike. We didn't get it back on for what, a couple of hours later.
I'll try to video it if possible.
Ciddyguy- I'd be interested to know whether you think Saturday's storm was the equal of the one in Sept. 2019. I missed the one in 2019 (was in Port Townsend where there was no action) but got to see the storm on Saturday. I got to see the one in May 2017 (which was actually a set of 3 storms, one while I was at work, one hit as I drove home, and one after I went to bed). That last set brought a lot of warm rain with it.
DeleteSeems to me that Seatac Airport and the Seattle forecasters need to keep an eye on this? Thunderstorms like this can cause a lot of wind shear as they move past. Is this similar to the thunderstorms that moved past SeaTac and disrupted operations in the 1990s as documented by the MIC at the time Brad Coman?
ReplyDeleteI'm glad I checked for any new posts today. I'm just taking a break from cleaning my gutters. Some of them were pretty bad.
ReplyDeleteHeading back out now. Looks like from the radar I've got about 45 minutes left to finish...maybe.
The highest wind speeds during August since the great 2015 windstorm are occurring at KBLI. Unusual weather for this area, with temperature ~70F and gusty 3 hours after sunset.
ReplyDeleteHat-tip! This forecast was spot-on. There was lightning and rolling thunder for hours up here, northern Cascades (Whatcom County). While at first the lightning seemed south and west of here, there were direct lightning strikes just after midnight as heavy cells passed through. I expected more rain with it - surprisingly, there was just .30 in "in the tube" this morning at seven, but the clouds are still heavy and the rain has become steady. VERY much appreciate the heads-up; closed windows, and prepared.
ReplyDeleteOkay, now it's the morning after.
ReplyDeleteThe roof has been power-washed, the gutters are sparkling inside and out, the window screens are totally free of dust and spider webs, the driveway and sidewalks are wearing nothing but a bit of remnant moisture, the deck is better than swept and the landscaping has all been well watered. My Sunday to-do list was rendered obsolete by the time I went to sleep last night!
Aside from the wonder and awe at the intensity of the meteorological performance - the strongest memory is an image of one of my downspouts literally looking like an open fire hydrant!
The raw power the atmosphere unleashed last evening was practically unbelievable. Each lightening bolt unleashing about 300 million volts and about 30,000 amps! I lost count of how many flashes, crashes and strikes I observed, but it was the most electrically prolific storm I've ever seen!
And then there is the rainfall! My location received 1.24" in the last 24 hours. According to a University of Arizona website a one-inch rain will collect 600 gallons from a 1,000 square foot roof, while 4,500 square foot lot will receive 2,800 gallons! I have a 7,500 square foot lot which, (unless my math is off), collected 4,667 gallons weighing 37,333 pounds or nearly 19 tons!!
I can't wait to read "Cliff's notes" on the hows and whys of that storm! I bet he didn't sleep a wink all night - relishing in the power and excitement and underpinnings of such an amazing display!
BNK: I looked at the CoCoRaHS map, at the morning figures. Are you in Redmond? I saw a 1.23" on the map. Sheesh, the storm had a really fascinating precip pattern.
DeleteYesterday, during this storm, I happened to be driving from Eugene to Issaquah, with a stop in Tillamook! 🧀
ReplyDeleteThe weather was merely cloudy in Eugene, started drizzling in Tillamook, we avoided the squall on I5 by staying on 101, which was windy but only drizzle until we hit the storm driving through Elma near Olympia. From there it was a full on downpour with wipers on overdrive and an amazing electric show in the skies and torrents filling the ruts on the road. Was less than ideal driving, but we made it home.
A quick update the morning after...
ReplyDeleteLots of flashes of the lightning variety, but no boomers, or none that I've encountered in Tacoma. It did rain good for a while, then let off.
The initial wind gusts popped the corrugated plastic sheeting out that blocks the open window above my window AC unit, so had to put that back in and in the process, shut the bedroom door. By the time I saw that, it was bedtime.
This morning, it's sunny with periodic clouds around and all is mostly dry.
No loss of power thankfully. The signs of lightning came before 8PM. I thought I saw a flash around 6PM, which got me to stir my stumps and go to the store for 3 items for dinner and get back before it got bad, which I did and while eating, saw it get dark earlier than normal this time of year and saw the first flashes looking west out of my kitchen window.
It got worse from there, and a direct bolt of lightning, I think a cloud/ground bolt at that appeared once to the south of me, but again, no booming of thunder so likely not very close but all around the city.
S. Everett report--A moderate storm after all...lots of lightning, but no serious damage done...the predicted high winds did not show up, hardly any tree branches, or wires down in my wooded neighborhood. Some rain...the biggest shock to me, was that the 40-50-mph predicted gusts never did happen....all in all, a very "Pacific" Northwest, not so terrible, weather event.
ReplyDeleteHi Cliff :-) We got a generous half inch of rain last night in South Everett area, and now it just hailed! It wasn't small hail either. Please tell me about how that happened because wow!! It was flying sideways and bouncing all over our porch. I took pics and video because I was so incredulous. Even little hail sounds pretty fierce in our porch's tin roof, so this was shockingly loud!
ReplyDeleteOn the 18th at about 15:00 in Shelton we got torrential rain and 1/2" to almost 1" hail balls. Even this morning they still haven't fully melted. Local Weather Underground PWS reported that we received nearly an inch of precipitation for the event that was about 20 minutes in duration. Parts of downtown were flooded. The lightning was more impressive on the evening of the 17th, but the thunder yesterday was some of the most intense I've ever experienced.
ReplyDeleteFinally a decent thunderstorm- the first in several years around here. And I got 1.3 inches of rain at my place on the Bothell-Mill Creek line.
ReplyDeleteDid this storm hit some sort of meteorlogical wall just south of Everett?
ReplyDeleteI experienced decent winds and rain, but the lightning never reached where I was.
For probably close to two hours, I was seeing lightning flashing to the south every 30 seconds to 1 minute each time I went out to the porch to watch, which is quite active for western Washington. Seldom was it less than 20 seconds until I heard the thunder, if I heard it at all. So it was generally staying about 4 miles away. A few strokes were around 3 miles, and a single stroke got as close as 2-1/2 miles.
So last night, around 5pm....S. Everett got hit by a powerful squall, lasting less than 30 minutes...extreme rain/hail, gusty winds, etc. Did not expect that to happen! Neither did my overflowing gutters, that I had recently cleaned.
ReplyDeleteAs said by others, the forecast was spot on. Pretty crazy storm in North Puyallup. Lightning and thunder at the same time with sheets of rain/hail and winds that seemed to turn itself on and off like a light switch. The yard looked like proper low pressure driven windstorm from the Fall/winter. Luckily no big trees came down and power stayed on, somehow. Shout out to PSE for their tree trimming efforts, they worked here.
ReplyDeleteInterested to know the cloud tops height and how many lightning strikes. I saw a blip on King 5 that showed about 3400 in 24hrs for WA and OR if I remember that correctly. I feel like all 3400 happened above Pierce county.