A Potent Storm with A Poisonous Tail Makes Landfall Today

A powerful Pacific cyclone is now approaching landfall and its powerful winds have already caused massive power outages over Oregon, where over 100,000 customers are in the dark as I write this.

Washington State is next.

Infrared satellite imagery shows the large-scale cyclone over the West Coast (see below).  Huge in scale.

A close-up visible image this morning shows the circulation with the low west of Westport.


Now the exciting part: the coastal radar on Langley Hill near Hoquiam is picking up the circulation offshore (see below).   Very helpful.  I always think appreciably of Senator Maria Cantwell when I see such images (she played a critical role in securing the hardware).


The Poisonous Tail

Oceanic midlatitude cyclones have a structure different than cyclones over land, and the current storm is no exception.

Below is the analysis of sea level pressure (solid lines) and wind gusts (color shading) at 4 AM this morning.   You will notice a large pressure change and strong winds on the Oregon Coast, which led to lots of power outages.  

But do you see the strongest winds and large pressure gradients to the south and west of the low center?  That is known as the "poisonous tail".  And that tail will reach western Washington later this afternoon.


The maximum winds from midnight to 9 AM today so far are shown below.  Exposed locations in the coastal mountains of western Oregon experienced 80-90 mph gusts, while 60-70 mph gusts raked the coast.   Southwest Washington had 50-60 mph gusts.  Strong winds also hit eastern Oregon.


The Forecast

This is not an easy forecast.  The winds at any particular location will be critically dependent on the exact path of the low

The UW model forecast has the low weakening a bit and moving across the northern Olympic Mountains by 1 PM, with a huge pressure gradient (and strong winds) over NW Oregon.  Not good for Portland.


By 10 PM tonight the low is in southern BC and a large pressure gradient is over western Washington.  The early evening will be the time of strongest winds over western WA.  Southerly winds over Puget Sound and powerful westerly winds in Strait.  Expect winds to accelerate in western Washington around 4 PM.


The NOAA/NWS HRRR model has a similar solution, and let me show you its latest forecast (started at 9 AM) for the strongest winds through 7 PM.

Strong winds (50 mph+) along the coast and Strait.  Central and northern Whidbey will be hit hard.  50 mph+ gusts from downtown Seattle to Olympia.  Crazy strong winds on exposed higher terrain of the central/southern Cascades.

The European Center model is taking the low on a more southerly path, which would be less threatening.

This storm is typical of one of the stronger cyclones we get each year, but not like one of the majors (Columbus Day, Inauguration Day, Chanukah Eve).  Its track is not optimal, it is weakening on landfall, and other reasons.

If you are living in western Washington, you would be wise to charge your electronics now and prepare for a power outage.  Stay inside during the strongest winds later this afternoon and evening.

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