Issued: 7:10 AM PDT Monday, March 19, 2018
by Robert Hahn

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k

Weather Synopsis for Monday & Sunday

A common spring-like weather pattern exists over the eastern north Pacific with several slow-moving low pressure circulations cut-off from the jetstream. A small-scale and weakening upper low is drifting S-SW off the coast of Oregon on Monday morning, moving the instability and shower activity south of our region as a weak upper ridge builds over the forecast area. 

Monday will bring fair weather with an isolated rain or snow shower possible and partly to mostly sunny skies with light winds.

The weak ridge will linger Monday night through Tuesday bringing continued fair weather with mostly clear skies. High clouds will begin increasing Tuesday afternoon as a frontal feature begins slowly approaching from the northwest through Tuesday night.

Freezing levels are typical for mid-March and show a strong diurnal signal.

Weather Forecast

Olympics
Monday Mostly sunny in the morning with clouds building in the afternoon with a very isolated shower possible.
Monday Night Becoming mostly clear.
Tuesday Mostly sunny with increasing high clouds in the afternoon.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Monday Mostly sunny in the south, partly cloudy in the north. Scattered cumulus clouds throughout in the afternoon with a very isolated shower possible.
Monday Night Becoming mostly clear.
Tuesday Mostly sunny with some high clouds arriving in the north in the afternoon.
East Slopes of the Washington Cascades
Monday Mostly sunny in the south, partly cloudy in the north. Scattered cumulus clouds throughout in the afternoon with a very isolated shower possible.
Monday Night Becoming mostly clear.
Tuesday Mostly sunny with some high clouds arriving in the north in the afternoon.
Mt. Hood
Monday Mostly sunny with scattered cumulus clouds developing in the afternoon with a very isolated shower possible.
Monday Night Becoming mostly clear.
Tuesday Mostly sunny in the morning becoming partly cloudy in the afternoon.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Monday Morning Freezing Level 3000' 3500' 4000' ' ' 3500' ' 3500'
Monday Afternoon Freezing Level 4000' 4000' 5000' ' ' 4500' ' 5000'
Monday Night Freezing Level 2500' 2500' 2000' ' ' 2000' ' 2500'
Tuesday Morning Freezing Level 4000' 4000' 5000' ' ' 4500' ' 5000'
Tuesday Afternoon Freezing Level 4000' 4500' 5500' ' ' 5000' ' 6000'
Hurricane Ridge Elevation
Monday Morning Freezing Level
3000'
Monday Afternoon Freezing Level
4000'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
4000'
Tuesday Night Freezing Level
3000'
Mt. Baker Elevation
Monday Morning Freezing Level
3500'
Monday Afternoon Freezing Level
4000'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
4500'
Tuesday Night Freezing Level
2500'
Washington Pass Elevation
Monday Morning Freezing Level
4000'
Monday Afternoon Freezing Level
5000'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
5000'
Tuesday Afternoon Freezing Level
5500'
Tuesday Night Freezing Level
3000'
Leavenworth Elevation
Monday Morning Freezing Level
'
Monday Afternoon Freezing Level
'
Monday Night Freezing Level
'
Tuesday Morning Freezing Level
'
Tuesday Afternoon Freezing Level
'
Tuesday Night Freezing Level
'
Stevens Pass Elevation
Monday Morning Freezing Level
'
Monday Afternoon Freezing Level
'
Monday Night Freezing Level
'
Tuesday Morning Freezing Level
'
Tuesday Afternoon Freezing Level
'
Tuesday Night Freezing Level
'
Snoqualmie Pass Elevation
Monday Morning Freezing Level
3500'
Monday Afternoon Freezing Level
4500'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
4500'
Tuesday Afternoon Freezing Level
5000'
Tuesday Night Freezing Level
2500'
Mt. Rainier & Crystal Elevation
Monday Morning Freezing Level
'
Monday Afternoon Freezing Level
'
Monday Night Freezing Level
'
Tuesday Morning Freezing Level
'
Tuesday Afternoon Freezing Level
'
Tuesday Night Freezing Level
'
Mt. Hood Elevation
Monday Morning Freezing Level
3500'
Monday Afternoon Freezing Level
5000'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
5000'
Tuesday Afternoon Freezing Level
6000'
Tuesday Night Freezing Level
3000'

* Easterly flow in the Cascade Passes can cause locally lower Snow or Freezing levels than areas further west.
Freezing Level is when no precipitation is forecast.

Precipitation Forecast

Sunday Sunday
Hurricane Ridge LT 0.10 LT 0.10
Mt Baker Ski Area LT 0.10 LT 0.10
Washington Pass LT 0.10 LT 0.10
Stevens Pass LT 0.10 LT 0.10
Snoqualmie Pass LT 0.10 LT 0.10
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.10 LT 0.10
Paradise LT 0.10 LT 0.10
White Pass LT 0.10 LT 0.10
Mt Hood Meadows LT 0.10 LT 0.10
LT 0.10 LT 0.10

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Monday Morning VAR 0 - 10 W 0 - 10 W 0 - 10 --- - W 5 - 15
Monday Afternoon W 5 - 15 WSW 5 - 15 W 5 - 15 --- - WNW 5 - 15
Monday Night WSW 5 - 15 WSW 5 - 15 W 5 - 15 --- - W 0 - 10
Tuesday Morning SW 5 - 15 SSW 5 - 15 WSW 5 - 15 --- - WSW 5 - 15
Tuesday Afternoon WSW 5 - 15 WSW 5 - 15 W 5 - 15 --- - W 5 - 15
Hurricane Ridge Elevation
Monday Morning VAR 0 - 10
Monday Afternoon W 5 - 15
Monday Night WSW 5 - 15
Tuesday Morning SW 5 - 15
Tuesday Afternoon WSW 5 - 15
Tuesday Night SSW 5 - 15
Mt. Baker Elevation
Monday Morning W 0 - 10
Monday Afternoon WSW 5 - 15
Monday Night WSW 5 - 15
Tuesday Morning SSW 5 - 15
Tuesday Afternoon WSW 5 - 15
Tuesday Night S 5 - 15
Stevens and Snoqualmie Pass Elevation
Monday Morning W 0 - 10
Monday Afternoon W 5 - 15
Monday Night W 5 - 15
Tuesday Morning WSW 5 - 15
Tuesday Afternoon W 5 - 15
Tuesday Night SSW 5 - 15
Mt. Rainier Elevation
Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Elevation
Monday Morning W 5 - 15
Monday Afternoon WNW 5 - 15
Monday Night W 0 - 10
Tuesday Morning WSW 5 - 15
Tuesday Afternoon W 5 - 15
Tuesday Night SW 0 - 10
Hurricane Ridge Direction - Speed
Monday Morning VAR 0 - 10
Monday Afternoon W 5 - 15
Monday Night WSW 5 - 15
Tuesday Morning SW 5 - 15
Tuesday Afternoon WSW 5 - 15
Tuesday Night SSW 5 - 15
Mt. Baker Direction - Speed
Monday Morning W 0 - 10
Monday Afternoon WSW 5 - 15
Monday Night WSW 5 - 15
Tuesday Morning SSW 5 - 15
Tuesday Afternoon WSW 5 - 15
Tuesday Night S 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Monday Morning W 0 - 10
Monday Afternoon W 5 - 15
Monday Night W 5 - 15
Tuesday Morning WSW 5 - 15
Tuesday Afternoon W 5 - 15
Tuesday Night SSW 5 - 15
Mt. Rainier Direction - Speed
Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Direction - Speed
Monday Morning W 5 - 15
Monday Afternoon WNW 5 - 15
Monday Night W 0 - 10
Tuesday Morning WSW 5 - 15
Tuesday Afternoon W 5 - 15
Tuesday Night SW 0 - 10

Directions above indicate the direction the wind blows from on the 16-point cardinal scale. These winds indicate "free" winds, or those winds in the atmosphere not influenced by terrain. Topographical effects may produce greater or lower wind speeds in certain locations as well as significant variations in direction.

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Monday Morning WNW 5 - 15 N 5 - 15 NW 5 - 15 --- - W 5 - 15
Monday Afternoon W 5 - 15 W 5 - 15 W 5 - 15 --- - W 5 - 15
Monday Night W 10 - 20 WSW 10 - 20 W 10 - 20 --- - WSW 10 - 20
Tuesday Morning W 10 - 20 WSW 10 - 20 W 10 - 20 --- - WSW 5 - 15
Tuesday Afternoon WSW 10 - 20 WSW 10 - 20 WSW 10 - 20 --- - WSW 5 - 15
Mt. Baker Direction - Speed
Monday Morning WNW 5 - 15
Monday Afternoon W 5 - 15
Monday Night W 10 - 20
Tuesday Morning W 10 - 20
Tuesday Afternoon WSW 10 - 20
Tuesday Night SW 10 - 20
Washington Pass Direction - Speed
Monday Morning N 5 - 15
Monday Afternoon W 5 - 15
Monday Night WSW 10 - 20
Tuesday Morning WSW 10 - 20
Tuesday Afternoon WSW 10 - 20
Tuesday Night SW 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Monday Morning NW 5 - 15
Monday Afternoon W 5 - 15
Monday Night W 10 - 20
Tuesday Morning W 10 - 20
Tuesday Afternoon WSW 10 - 20
Tuesday Night SW 10 - 20
Mt. Rainier Direction - Speed
Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Mt. Hood Direction - Speed
Monday Morning W 5 - 15
Monday Afternoon W 5 - 15
Monday Night WSW 10 - 20
Tuesday Morning WSW 5 - 15
Tuesday Afternoon WSW 5 - 15
Tuesday Night SW 15 - 25

Directions above indicate the direction the wind blows from on the 16-point cardinal scale. These winds indicate "free" winds, or those winds in the atmosphere not influenced by terrain. Topographical effects may produce greater or lower wind speeds in certain locations as well as significant variations in direction.

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k

Previous forecast from Mar 16, 2018

The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.