Issued: 2:15 PM PDT Wednesday, April 2, 2014
by Dennis D'Amico

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

Weather Synopsis for Wednesday & Monday

A transitory upper level ridge along the coast will continue to shift inland today. Low level moisture banked along the west slopes of the Cascades this morning has lifted and partially scattered this afternoon. An afternoon increase in high clouds from an approaching frontal system should average to a partly sunny day for the Olympics and west slopes side and mostly sunny along the east slopes.   

High clouds should increase further Wednesday night and begin to lower Thursday morning.   A north-south oriented frontal band will slowly move inland on Thursday.  Precipitation timing has been pushed back slighlty with the afternoon update; light precipitation should hold off until Thursday afternoon for the Cascades, and even a bit later for Mt. Hood on Thursday.  More of a southerly component with this front should somewhat favor the volcanoes and south slopes.  Easterly flow may locally keep light wet snow at Snoqualmie Pass through Thursday evening despite slightly higher free-air snow levels.   

The front should stall over the area Thursday evening until the upper level trough axis finally comes Thursday night and transitions light rain and snow to showers.    

Weather Forecast

Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Wednesday

Partly sunny with increasing high clouds in the afternoon. 

Wednesday Night

Becoming cloudy overnight.  

Thursday - Thursday Evening

Clouds lowering with light rain and snow developing in the afternoon, becoming occasionally moderate volcanoes in the evening. Snow levels initially cooler Cascade Passes due to easterly flow. 

East slopes of the Washington Cascades
Wednesday

Mostly sunny with increasing high clouds in the afternoon. 

Wednesday Night - Thursday Morning

Becoming cloudy overnight.  

Thursday Afternoon - Thursday Evening

Clouds lowering with light rain and snow developing Thursday afternoon. 

Mt. Hood Area
Wednesday

Partly sunny with increasing high clouds in the afternoon. 

Wednesday Night

Becoming cloudy overnight.  

Thursday - Thursday Evening

Light rain and snow developing Thursday afternoon and becoming light to occasionally moderate Thursday evening.  

Olympics
Wednesday

Partly sunny with increasing high clouds in the afternoon. 

Wednesday Night

Becoming cloudy overnight.  

Thursday - Thursday Evening

Clouds lowering with light rain and snow developing in the morning, becoming occasionally moderate south slopes in the afternoon and evening. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Wednesday Afternoon Freezing Level 4500' ' ' ' ' 5000' ' 5500'
Wednesday Night - Thursday Morning Freezing Level 3500' ' ' ' ' 3500' ' 4000'
Thursday Mid-day - Thursday Evening Snow Level * 4000' ' ' ' ' 4000' ' 4500'
Hurricane Ridge Elevation
Wednesday Afternoon Freezing Level
4500'
Wednesday Night - Thursday Morning Freezing Level
3500'
Thursday Mid-day - Thursday Evening Snow Level
4000'
(Easterly Flow *)
Thursday Night Snow Level
3500'
Mt. Baker Elevation
Wednesday Afternoon Freezing Level
'
Wednesday Night - Thursday Morning Freezing Level
'
Thursday Mid-day - Thursday Evening Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
Washington Pass Elevation
Wednesday Afternoon Freezing Level
'
Wednesday Night - Thursday Morning Freezing Level
'
Thursday Mid-day - Thursday Evening Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
Leavenworth Elevation
Wednesday Afternoon Freezing Level
'
Wednesday Night - Thursday Morning Freezing Level
'
Thursday Mid-day - Thursday Evening Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
Stevens Pass Elevation
Wednesday Afternoon Freezing Level
'
Wednesday Night - Thursday Morning Freezing Level
'
Thursday Mid-day - Thursday Evening Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
Snoqualmie Pass Elevation
Wednesday Afternoon Freezing Level
5000'
Wednesday Night - Thursday Morning Freezing Level
3500'
Thursday Mid-day - Thursday Evening Snow Level
4000'
(Easterly Flow *)
Thursday Night Snow Level
3500'
Mt. Rainier & Crystal Elevation
Wednesday Afternoon Freezing Level
'
Wednesday Night - Thursday Morning Freezing Level
'
Thursday Mid-day - Thursday Evening Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
Mt. Hood Elevation
Wednesday Afternoon Freezing Level
5500'
Wednesday Night - Thursday Morning Freezing Level
4000'
Thursday Mid-day - Thursday Evening Snow Level
4500'
(Easterly Flow *)
Thursday Night Snow Level
3500'

* 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

Monday Monday
Hurricane Ridge LT 0.10 LT 0.25
Mt Baker Ski Area LT 0.10 0 - 1.00
Washington Pass LT 0.10 0.25 - 0.50
Stevens Pass LT 0.10 0.25 - 0.50
Snoqualmie Pass LT 0.10 0 - 0.50
Mission Ridge LT 0.10 LT 0.25
Crystal Mt LT 0.10 0 - 0.50
Paradise LT 0.10 0 - 0.75
White Pass LT 0.10 0.25 - 0.50
Mt Hood Meadows LT 0.10 0.50 - 0.75
LT 0.10 0.50 - 0.75

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Wednesday Afternoon - Wednesday Night SW 5 - 15 --- - W 5 - 15 --- - W 5 - 15
Thursday Morning S 10 - 20 --- - SW 5 - 15 --- - SW 5 - 15
Thursday Mid-day - Thursday Afternoon SSW 15 - 25 --- - S 10 - 20 --- - SW 10 - 20
Hurricane Ridge Elevation
Wednesday Afternoon - Wednesday Night SW 5 - 15
Thursday Morning S 10 - 20
Thursday Mid-day - Thursday Afternoon SSW 15 - 25
Thursday Night SW 15 - 25
Mt. Baker Elevation
Wednesday Afternoon - Wednesday Night --- -
Thursday Morning --- -
Thursday Mid-day - Thursday Afternoon --- -
Thursday Night --- -
Stevens and Snoqualmie Pass Elevation
Wednesday Afternoon - Wednesday Night W 5 - 15
Thursday Morning SW 5 - 15
Thursday Mid-day - Thursday Afternoon S 10 - 20
Thursday Night SW 15 - 25
Mt. Rainier Elevation
Wednesday Afternoon - Wednesday Night --- -
Thursday Morning --- -
Thursday Mid-day - Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Elevation
Wednesday Afternoon - Wednesday Night W 5 - 15
Thursday Morning SW 5 - 15
Thursday Mid-day - Thursday Afternoon SW 10 - 20
Thursday Night SW 15 - 25
Hurricane Ridge Direction - Speed
Wednesday Afternoon - Wednesday Night SW 5 - 15
Thursday Morning S 10 - 20
Thursday Mid-day - Thursday Afternoon SSW 15 - 25
Thursday Night SW 15 - 25
Mt. Baker Direction - Speed
Wednesday Afternoon - Wednesday Night --- -
Thursday Morning --- -
Thursday Mid-day - Thursday Afternoon --- -
Thursday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Afternoon - Wednesday Night W 5 - 15
Thursday Morning SW 5 - 15
Thursday Mid-day - Thursday Afternoon S 10 - 20
Thursday Night SW 15 - 25
Mt. Rainier Direction - Speed
Wednesday Afternoon - Wednesday Night --- -
Thursday Morning --- -
Thursday Mid-day - Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Afternoon - Wednesday Night W 5 - 15
Thursday Morning SW 5 - 15
Thursday Mid-day - Thursday Afternoon SW 10 - 20
Thursday 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.

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Wednesday Afternoon --- - --- - NW 15 - 25 --- - NW 10 - 20
Wednesday Night - Thursday Morning --- - --- - SW 10 - 20 --- - SW 10 - 20
Mt. Baker Direction - Speed
Wednesday Afternoon --- -
Wednesday Night - Thursday Morning --- -
Thursday Afternoon - Thursday Night --- -
Washington Pass Direction - Speed
Wednesday Afternoon --- -
Wednesday Night - Thursday Morning --- -
Thursday Afternoon - Thursday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Afternoon NW 15 - 25
Wednesday Night - Thursday Morning SW 10 - 20
Thursday Afternoon - Thursday Night SW 20 - 30
Mt. Rainier Direction - Speed
Wednesday Afternoon --- -
Wednesday Night - Thursday Morning --- -
Thursday Afternoon - Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Afternoon NW 10 - 20
Wednesday Night - Thursday Morning SW 10 - 20
Thursday Afternoon - Thursday Night SW 25 - 35

Extended Weather Synopsis for Monday night through Monday

Scattered showers at cool snow levels should follow on Friday with NW flow aloft. Showers should decrease Friday night.  A wetter pattern with a warming trend looks likely for the weekend.  A warm frontal band in westerly flow aloft should spread light rain and snow over the area early on Saturday at moderate snow levels with a gradual warming trend and uptick in the precipitation intensity during the day.  The heaviest precipitation looks most likely to occur Saturday night. Another warm frontal system with higher snow levels may impact the area on Sunday as upper level ridging begins to build along the California coastline.  The ridge looks likely to build and lead to drier weather for the PNW early next week.    

Extended Weather

Olympics, Washington Cascades and Mt. Hood area
Friday - Friday Night

Mostly cloudy with scattered light to occasionally moderate rain and snow showers decreasing Friday night. 

Saturday

Light rain and snow becoming light to moderate Saturday afternoon with a gradual warming trend. 

Saturday Night

Moderate rain and snow with increasing winds. 

Sunday

Light rain and snow with further warming. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Friday - Saturday Morning Snow Level ' - ' 3000' - 4000' 3500' - 4500'
Saturday Mid-day - Saturday Night Snow Level ' - ' 4000' - 5000' 4500' - 5500'
Mt. Baker Elevation
Friday - Saturday Morning Snow Level
' - '
Saturday Mid-day - Saturday Night Snow Level
' - '
Sunday Snow Level
' - '
Snoqualmie Pass Elevation
Friday - Saturday Morning Snow Level
3000' - 4000'
Saturday Mid-day - Saturday Night Snow Level
4000' - 5000'
Sunday Snow Level
5000' - 6000'
Mt. Hood Elevation
Friday - Saturday Morning Snow Level
3500' - 4500'
Saturday Mid-day - Saturday Night Snow Level
4500' - 5500'
Sunday Snow Level
6000' - 7000'

* 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.

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

Previous forecast from Apr 2, 2014

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.