Thursday, May 23, 2013

Memorial Weekend Forecast

Memorial Day is not a dependable weekend around the Northwest...never has been, never will be.    Generally we have a sunny, warm period in the middle of May (early May this year) and then we move towards the June gloom mode of low clouds.

During the past few days we have had a closed upper low hanging over us (see graphic), with showers circling around, sometimes from the unusual easterly direction.

With the low right over western Washington today, most of the shows have gone south of Puget Sound, hitting the Oregon coast and Willamette Valley quite hard, with some places getting 1-2 inches of rain.   The next 24h will be more of the same (see graphic), with rain over Oregon, but very little north of Olympia.  Northwest Washington would be a good place for a Friday hike or walk.

I have good news and bad news for the rest of the weekend.  The good news is that low will open up and weaken.  There will be major breaks.  The bad news is that the low/trough will hang around for much of the weekend, with some showers and plenty of clouds in the west.  Oregon will be much wetter than Washington.

Saturday will be bring clouds and some light rain showers over and west of the Cascade crest.  Here is the 24 h total precipitation ending 5 PM on Saturday.  Not the best day for a hike on the western slopes of the Cascades, and the Oregon coast will be damp.

But Sunday looks much better over Washington, but still quite wet  over western Oregon. (24 h precipitation ending 5 PM Sunday is found below).

On Monday, a frontal system will be approaching the NW,  but it will begenerally dry over Washington, except for the crests and windward slopes of the Cascades.  Here is the forecast of precipitation at 5 PM on Monday. 

Eastern Washington is a good bet over the weekend for sun and warm temperatures (60s and 70s).    And with the I5 bridge over the Skagit River collapsed, it will be a tough ride north on I5 through Mt. Vernon.

One good thing about the cool, damp period of the past few days has been a substantial freshening of the snow about 3500 ft.  Some good late-season cross country skiing and the Cascade and Olympic Mt. snowpack is well above 100% of normal.





3 comments:

Pizza Guy said...

Thirty years ago, it did hit 90 degrees on Memorial Day Weekend in Bellingham. I had the great good fortune to be on a boat cruise in the San Juans that Saturday. OTOH, if I ever get skin cancer, that weekend will be to blame.

Jim Stout said...

I'm glad to see that at least heating in Olympia won't be needed for the Memorial day weekend. I don't care what the weather is like, I'm going to enjoy it to the fullest. You can't let a little rain ruin your weekend.

Michael said...

Strong consistent rain over the SJIs all this morning....what happened to "Sunday looks much better"...well at least I won't have to water....