Saturday, March 10, 2018

Monday's Temperatures Will Amaze

Temperatures got into the upper 50s today across western Washington...but you haven't seen nothing yet. And unusual easterly winds will really rev up during the next 24 hours or so.

The air aloft has warmed considerably during the past day under southerly flow, and an offshore pressure gradient has initiated easterly (from the east) flow over the Cascades.  To illustrate the profound warm up of the next few days, here are the surface air temperature forecasts for 4 PM today (Saturday), 5 PM tomorrow (Sunday), and 4 PM Monday.  A big surge of warmth over the next 48h. 

Sunday will get into the mid-60s for most.  But look at lots of folks in western WA will experience 70s F.

One driver of the warmth will be easterly flow, with strong downslope warming over the western slopes of the Cascades.  Air get compressed as it descends from higher to lower altitudes, and compression causes warming (like you notice when you use an air pump).

Here are the wind gusts predicted for 5 PM on Monday.  20-30 knot gusts from the southeast, particularly from central/south Seattle and eastward.  Another area east of Everett.    Why?  Because there are major low-areas in the Cascades:  Stampede Gap south of I90 and the Steven's Pass gap to the north. When there is a large pressure difference across the Cascades, air accelerates eastward through these low regions.

Such southeasterly winds often produce turbulent flights for those landing/taking off from Sea-Tac Airport.

But what will be really unusual next week will be the large amount of precipitation that will hit California due to a strong low center setting up west of northern CA.

Here are the two 72 hr totals for the next next 144 hours.  In WA state we will get some sprinkles, but California, and particularly the Sierra Nevada, will get hit by many inches of water and feet of snow over high terrain.   And more is predicted the following week.  I suspect fewer people will be talking about California drought when the next few weeks are over.


sunsnow12 said...

"I suspect fewer people will be talking about California drought when the next few weeks are over."

Only if there is a Cliff Mass in California that tells the truth about it. Which there isn't.

So I suspect the drought-mongers will continue to be out in full force in California. It's what they do, year around, and they do it for a reason. And it has nothing to do with truth.

Want to read up on it? Just google "permanent drought California".

On another subject... the bluest skies you've ever seen are in Seattle, and they wrote that song for days like today!

Karen Grooms said...

One more day of glorious Sun. Bring it! And please pass the Aleve: I'm not easing in...full throttle gardening mode!

Ansel said...

Sunsnow... But the most striking azure blue skies are at high altitude. Say the top of Mt. Rainier.

Had a nice hike up Mt. Si... so, it seemed, did half of Seattle. There was snow the last one and a half miles or so.

RogerG said...

I got to experience Föhn winds first hand while driving to Stevens this morning (around 8:15): Winds picked up between Monroe and Sultan. Then, within five miles/five minutes between Sultan and Startup, the temperature went from 41 deg to 55 deg.

John K. said...

"the bluest skies.." I think that lyric was just a Hollywood invention, completely unrealistic for these parts. Deep blue skies will be found where there is low humidity and particulates, or as Ansel notes, with altitude. That's not here!

John said...

Definitely amazing temps today at NAS Whidbey! Warmer than most summer days.

Rod said...

Sunsnow is a laugh a minute. He/she thinks only Washington state has scientists that know what they are talking about? Clueless.