June 03, 2024

A Winter Storm in June

A combination of heavy rain and wind, more reminiscent of November than June, came through yesterday and this morning, and the effects were substantial.

Winds gusting to 35-50 mph, acting on fully leafed out trees, led to massive loss of branches and trees.   My bicycle commute to the UW along the tree-lines Burke-Gilman trail was interrupted by several major treefalls (see picture below).

Tens of thousands of Seattle City Light customers lost power this morning.   Same for Puget Sound Energy.



Below is a plot of maximum winds overnight. Some mountain locations gusted over 60 mph, with over 45 mph near Puget Sound, the Strait, and the Washington coast.


Why were the winds so strong?   

The figure below shows the sea level pressure (solid lines) at 8 AM this morning.  A Pacific low-pressure system passed north of western Washington, creating a large north-south pressure difference that accelerated the winds northward.


Precipitation totals?   Over the past 36 h (see below), the western slopes of the Cascades and Coastal Mountain received 2-4.5 inches.... a lot for June.


Puget Sound was rainshadowed by the Olympics and Seattle "only" received about 1 inch.  

If you really want world-class mountain rainshadowing, head to a station just south of Port Townsend, which only received 0.11 inches over the same period (see red arrow).  No wonder folks retire there.


Forecasts were excellent for this event.  

Western Washington and Oregon rivers are running very high now, some at record levels (see below, blue and black dots are much, much higher than normal).


I hope the Drought Monitor folks will consider dropping the "moderate drought" designation for the western Cascades slopes.

More showers are occurring today across the region, as shown by the latest radar image (see below)


And the precipitation is not over!  Another plume of water vapor (a.k.a. an atmospheric river) is rapidly approaching (see water vapor satellite image below)


Rain will rev up tomorrow morning. By the time precipitation ends Wednesday AM, substantial rainfall will have occurred, particularly over the north Cascades and mountain of SW British Columbia (see 48 h total ending 5 AM Wednesday below).


Enjoy this wet interlude.  Drier conditions and a slow warm-up are expected Wednesday through Saturday, as our highs climb into the mid-70s.

12 comments:

  1. Nws seattle mentioned even stronger winds with Tuesday storm and issued a wind advisory for it, more damage on the way.

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  2. My weather station in Port Ludlow showed only 0.24" of rain yesterday. Most of it was very light almost 'misty'. I'm in a somewhat wind-protected area (about 1/2 mile inland from the Port Ludlow marina), so winds were 2-5mph with gusts to 10mph. Definitely in the 'rain shadow' here.

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  3. In Tacoma it's been mostly wet and blustery today, and the lights would occasionally blip but not the computer I was on. At almost 4pm, it's dry at the moment, winds are currently breezy. Even yesterday was rather wet as well.

    Don't know how much we got, but I believe even Tacoma gets the rain shadow too.

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  4. It was definitely not a June-ish weather event, but maybe we in Edmonds were spared because we didn't get near the amount of rain that was advertised and even the winds weren't as tree-knocking as I was led to believe they were going to be. Still, a very impressive storm for June!

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  5. This June rainstorm is impressive but far from biblical. The Snoqualmie peaked at just over 50 feet, well below the 54 feet predicted in your blog a few days ago. Meanwhile, NOAA is still predicting summer drought in WA in its May 31 update. The near-term forecasts are consistent with that. Maybe a bit premature to call off the drought?
    https://www.cpc.ncep.noaa.gov/products/expert_assessment/season_drought.png

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    Replies
    1. Jerry....if you mean raining for 40 days and nights...no. The Snoqualmie peak level was the prediction of the NOAA/NWS River Forecast Center, not my blog. The NOAA prediction is already wrong based on the current event. These seasonal predictions have very marginal skill..cliff

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  6. Ellensburg airport (KELN) reported a gust of 53 on Monday at 10:53 AM. There were lots of 40 mph gusts during the day. Average was plus or minus 30. This has been unpleasant to work in, but there's been no damage that I've seen. Very little rain.

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  7. The Drought Monitor folks consider dropping the "moderate drought" designation for the western Cascades slopes. Not a chance. Not while the Seattle Times Climate Lab is raking in funding from The Bullitt Foundation, Mike and Becky Hughes, University of Washington and Walker Family Foundation, and its fiscal sponsor is the Seattle Foundation. The social pressures to have courage are too great.

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  8. Speaking of the Drought Monitor, Cliff, did you see this piece in the LA Times? https://www.latimes.com/environment/story/2024-06-03/can-the-u-s-drought-monitor-keep-up-with-climate-change

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    Replies
    1. Thanks Pete....I looked at it. Makes no sense at all. The Drought Monitor is supposed to reflect current conditions....has nothing to do with climate change. In any case, Drought Monitor is completely subjective and near useless. It has drought over our region right now with surging rivers above normal and saturated soils...cliff

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  9. The National Interagency Fire Center (nifc.gov) has the year-to-date data and the 10 year average to-date exactly the same.
    Fires: 16,762 Acres: 1,969,354

    Down to the last 4 acres! That strains my probability monitor.

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  10. Is it just me, or did NWS completely miss the mark with the wind advisory? At least from my station observation in Shoreline and Everett Paine Field I noticed the winds peaked, before, and after the wind advisory, but not during. One of my stations which is fairly exposed in the Richmond Beach neighborhood recorded a gust of 35mph (strongest over the 3 days) just after 1pm June 4th, 2 hours after the wind advisory expired. There are a couple of trees near by so I know that wasn't the real number, was likely closer to 45-50mph. Paine field shows a similar pattern. Media seemed to hype up the amount of rain expected, but said very little about any wind, which I think caught a lot of folks off guard.

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