THREE Atmospheric Rivers Heading Our Way

Washington State and southern Brtish Columbia have experienced a very wet fall so far, with the atmospheric river of last weekend causing substantial flooding over Northwest Washington and the lower Fraser River Valley.

But mother nature is not done with us...we should not expect weather forbearance, considering that Thanksgiving week is climatologically the wettest, stormiest period of the year.

Meteorological ground zero, so to speak.

And to make the message clear:  not one, not two, but THREE significant atmospheric rivers will affect our region during the next seven days, with southern British Columbia getting the worst of it.

Let me show you the predicted distributions of atmospheric moisture from the UW WRF modeling system.

First, Thursday morning, with a potent atmosphere river of subtropical moisture aimed for northwest Washington State and southern BC.  A wet turkey day.  Sorry.


By Saturday night ANOTHER atmosphere makes landfall in the same place! 


And Tuesday afternoon an EVEN STRONGER atmospheric river takes aims on southern British Columbia.


How much rain is expected?  I will show you the accumulated totals through three times during the next week....and don't continue if you are meteorologically squeamish.

Through 4 PM Thrusday  there is up to five inches in the mountains of southwest BC and northwest Washington.  Puget Sound will get wet, but somewhat rain shadowed by the Olympics.

The total through 4 PM Saturday is more serious, with totals approaching 10 inches over the windward slopes of the mountains of Vancouver Island and the northern extension of the Cascades.

And by 4 PM Tuesday, things are getting serious with more than 10 inches over extensive areas of southwestern BC.  There is going to be flooding.  One good thing:  it appears that the North Cascades and Fraser River Valley will be out of the central plume of moisture--but wet enough.

And I have some soggy news to tell you about the future.  The latest extended forecast of the European Center through January 7 projects wetter than normal conditions (see below).  Sorry.  Of concern is the lack of precipitation in California... they acutely need it.



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