Atmospheric River Fest: A Very Wet Week

This has been a fairly wet winter so far, with recurring atmospheric river events here in the Pacific Northwest, and this week is going to be a wet repeat.

You don't need to be a meteorologist to appreciate the message of the latest infrared satellite image for the NE Pacific (see below):  a band of clouds stretching from west of Hawaii to our door.

And the forecast total moisture in a vertical column of air (column-integrated water vapor) for tomorrow at 4 PM shows the atmospheric river signature, with high values of water vapor coming in to us from the west.

The flow during the atmospheric river events this week will generally be associated with westerly flow, which produces big amounts on our local mountains but leaves central Puget Sound in the rainshadow of the Olympics.

Here is the total precipitation forecast by the UW WRF model for the next 72 (through Tuesday at 4 AM). 5-10 inches of liquid water in the WA Cascades and SE British Columbia.  But only about a half-inch around Seattle to Port Townsend. (click to enlarge)

Less precipitation but still wet for the next 72 hr, with California sharing in the bounty.

The pattern is going to stay with us for a while, here is the predicted total for the next 384 hr (through Feb. 29th at 4 AM).  Very wet from northern CA into SE Alaska.   But completely dry over southern CA.  Palm Springs is going to be amazing--dry with temperatures heading to the upper 80s this week.  And they sell date shakes down there.  Why doesn't anyone invite me to give weather talks down there?

 Now, some of you will want to know about snow.  Don't ask.   The air will be relatively warm and the snow levels will be around 6000 ft.   Rain will fall on the lower ski areas, like Snoqualmie and Stevens, but higher elevations should get some....here is the forecast for the next 72 h.

As shown by the graphic below (SNOTEL observations), WA state snowpack is now very close to 100% of normal, well down from where we were a month ago.

 I suspect that with the continuation of the El Nino impacts we will slowly slide down to around 80% on April 1, hugely better than last year.  The drought is over folks.

Northwest Weather WorkshopThe big local weather workshop is less than a month away (March 4-5, Seattle).  If you are interested in attending, the agenda and registration information can be found here.  This gathering is the place to be if you want to learn more about local weather research and operations.