January 24, 2021

A Mini-Hurricane Hits the Washington Coast

The imagery from the Langley Hill radar near Hoquiam was quite extraordinary this morning.  

At 10:10 AM there was a clear, precipitation-free "eye" with heavy precipitation bands circling around it as the feature came ashore near the the northern tip of the Long Beach peninsula.

If it wasn't for the scale, would be wondering whether we were looking at the Gulf Coast in September!  And a close look a few minutes later showed the "eye" sliding eastward just south of Westport.


This little "hurricane" packed some wallop, with eye associated with a small, intense  low pressure center and strong winds.

Consider the situation at Toke Point (see map), where winds gusted to 40 knots (47 mph) at 1036 AM, dropped to 11 knots in the "eye" and rebounded  to 17 knots on the other side (see plot below).


The sea level pressure plummeted to 1004 hPa (29.65 inches of mercury) at the center of the low.


A surface map at 9 AM, shows the mini-low ready to move inland, with a pressure of 1004.7 hPa and rapid pressure falls at buoy 46099.


The mini-low was not very apparent in satellite imagery at 10:30 AM (see below) and was not well forecast by high resolution modelings systems such as the UW WRF model or the NWS HRRR modeling system.  For example, the UW 


 modeling system initialized at4 PM on Saturday, had two lows, with none in the right place (see below).  Hard to get such small-scale features correct coming off the relatively data poor lower atmosphere of the Pacific.


But one thing is sure:  this event clearly demonstrated the value of having a coastal radar, which can document small scale features that are not apparent even in the best satellite data.  The Oregon coast, which has essentially no radar coverage for its southern half, desperately needs a coastal radar.  

Senator Cantwell helped secure a coastal radar for Washington; an Oregon Senator needs to step up to the plate.










12 comments:

  1. One of our lame senators lives in New York

    ReplyDelete
  2. Interesting...but the terminology is confusing...earlier posts concerning storms insist that all of our storms are "extra-tropical" storms...but in this case, a small storm can be labeled as being a type of "hurricane"?

    ReplyDelete
    Replies
    1. I think you're taking it too literally.

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    2. That's funny everyone else calls them typhoons on then pacific and hurricanes on the Atlantic. Is this just a distraction from the previous 5 blog entry that call for snow? I have a real hard time with washington weather predictions. Cant predict tomorrow correctly but can tell me snow is coming a week from when it should. Almost like talking windstorms all fall long, only to not even mention/predict the biggest one this year that knocked out power to half a million... the best storms, wind, rain, snow are hardly ever properly predicted. Time for some new meteroligcal hardware in washington as well apprently

      Delete
  3. I just want to know when a significant amount of snow will be back in the mountains. We’re going on 3 weeks of nada

    ReplyDelete
    Replies
    1. Snoqualmie Pass (lowest pass in WA, 3k elevation): 1/12: 23"; 1/14: 3.5"; 1/21: 1"; 1/22: 1"; 1/25: 5"

      And since 1/6 is still within the "3 weeks" window you are claiming let's add an additional 16". So that's 4 feet in the last 3 weeks including 5 inches last night (which had been recorded and posted when you made your comment).

      Current forecast shows snow in 8 out of the next 10 days at Snoqualmie Pass. Forecasts are readily available everywhere and so are stats.

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    2. Nothing significant..since 1/6. The 1/12 storm you are talking about and onward are at higher elevations 5k.

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    3. You are 100% wrong: https://www.wsdot.com/traffic/passes/snowdepth/ - (WSDOT measurements at pass level, 3,015')

      And an article from 1/12 spelling it out: Snoqualmie Pass Has Had 236 Inches of Snow So Far This Season - The Most in 10 Years:

      https://www.thenewstribune.com/news/state/washington/article248456800.html

      Delete
  4. Probably not for 2 weeks or so. There will be some snowfall between now and then, but nothing approaching substantial. California is stealing all the goods. The Southern Washington and Oregon Cascades should fare pretty well.

    ReplyDelete
    Replies
    1. Because 236" and "the most in 10 years" isn't substantial. Got it.

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  5. Talk about another major miss in forecast. For decades a 100% reliable indicator was a snow level of 1000' as reported by the NWS at White Pass would get me at least a dusting of snow and zero rain. Now, even at 500', nothing. A few flakes mixed in with rain and 33F.
    30 years ago, at this exact same spot, with amount of precip, with the reported snow level, I should have had a solid foot plus of snow.

    ReplyDelete

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

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