Issued: 1:41 PM PDT Thursday, March 23, 2017
by Garth Ferber

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

Weather Synopsis for Thursday & Thursday

A mostly weak front and slightly splitting upper trough moved across the Northwest on Wednesday. But the NWAC station at Mt Baker had 11 inches of new snow on Thursday morning. Other NWAC stations along the Cascade west slopes above the Pass levels had 2-5 inches.

A warm front also brushed mainly the Olympics and north Cascades on Thursday morning.

A minor upper ridge will cross the Northwest and weak surface high pressure will weakly and temporarily build north over the Northwest on Thursday.

Southwest flow will then rapidly carry a front across the Northwest Thursday night.

A slight break in showers is indicated following the front Friday morning.

An upper trough will move to the Northwest on Friday but with the main flow, moisture and trailing portion of the front sinking south to California. But renewed showers should be seen over the Olympics and Cascades on Friday afternoon.

Weather Forecast

Olympics
Thursday Morning - Thursday Afternoon

Mostly cloudy. Increasing light rain or snow in the late afternoon.

Thursday Night

Increasing clouds and increasing moderate occasional heavy rain or snow. Increasing moderate alpine winds.

Friday Morning

Mostly light showers. Moderate alpine winds.

Friday Afternoon

Renewed mostly moderate showers. Moderate alpine winds.

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

Mostly cloudy north. Partly cloudy central. Partly sunny south.

Thursday Night

Increasing clouds and increasing moderate occasional heavy rain or snow. Increasing moderate alpine winds.

Friday Morning

Mostly light showers. Moderate alpine winds.

Friday Afternoon

Renewed moderate occasional heavy showers heaviest on the volcanoes. Moderate alpine winds.

East slopes of the Washington Cascades
Thursday Afternoon

Partly sunny north part. Mostly sunny south part.

Thursday Night

Increasing clouds and increasing light to moderate rain or snow. Increasing moderate alpine winds.

Friday Morning

Mostly light showers mainly higher elevations. Moderate alpine winds.

Friday Afternoon

Renewed light to moderate showers. Moderate alpine winds.

Mt. Hood Area
Thursday Afternoon

Mostly sunny.

Thursday Night

Increasing clouds and increasing moderate occasional heavy rain or snow. Increasing moderate alpine winds.

Friday Morning

Mostly light showers. Moderate alpine winds.

Friday Afternoon

Renewed moderate occasional heavy showers. Moderate alpine winds.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Thursday Afternoon Snow Level * 4500' 4000' 4000' ' ' 4500' ' 5000'
Thursday Night - Friday Morning Snow Level 4000' 3000' 3000' ' ' 4000' ' 5000'
Friday Afternoon Snow Level 4500' 4000' 4000' ' ' 4500' ' 5000'
Hurricane Ridge Elevation
Thursday Afternoon Snow Level
4500'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
4000'
Friday Afternoon Snow Level
4500'
Friday Night Snow Level
3000'
Mt. Baker Elevation
Thursday Afternoon Snow Level
4000'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
3000'
Friday Afternoon Snow Level
4000'
Friday Night Snow Level
3000'
Washington Pass Elevation
Thursday Afternoon Snow Level
4000'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
3000'
Friday Afternoon Snow Level
4000'
Friday Night Snow Level
2000'
Leavenworth Elevation
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Stevens Pass Elevation
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Snoqualmie Pass Elevation
Thursday Afternoon Snow Level
4500'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
4000'
Friday Afternoon Snow Level
4500'
Friday Night Snow Level
3000'
Mt. Rainier & Crystal Elevation
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Mt. Hood Elevation
Thursday Afternoon Snow Level
5000'
(Easterly Flow *)
Thursday Night - Friday Morning Snow Level
5000'
Friday Afternoon Snow Level
5000'
Friday 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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Thursday Afternoon SSE 25 - 35 SSE 15 - 25 SSE 10 - 20 --- - SSE 10 - 20
Thursday Night SSE 25 - 35 SSE 20 - 30 SSE 20 - 30 --- - SSE 20 - 30
Friday Morning SW 25 - 35 SSW 20 - 30 SW 15 - 25 --- - SW 15 - 25
Friday Afternoon SW 25 - 35 SW 20 - 30 SW 20 - 30 --- - SW 20 - 30
Hurricane Ridge Elevation
Thursday Afternoon SSE 25 - 35
Thursday Night SSE 25 - 35
Friday Morning SW 25 - 35
Friday Afternoon SW 25 - 35
Friday Night SW 15 - 25
Mt. Baker Elevation
Thursday Afternoon SSE 15 - 25
Thursday Night SSE 20 - 30
Friday Morning SSW 20 - 30
Friday Afternoon SW 20 - 30
Friday Night SW 15 - 25
Stevens and Snoqualmie Pass Elevation
Thursday Afternoon SSE 10 - 20
Thursday Night SSE 20 - 30
Friday Morning SW 15 - 25
Friday Afternoon SW 20 - 30
Friday Night SW 15 - 25
Mt. Rainier Elevation
Thursday Afternoon --- -
Thursday Night --- -
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Mt. Hood Elevation
Thursday Afternoon SSE 10 - 20
Thursday Night SSE 20 - 30
Friday Morning SW 15 - 25
Friday Afternoon SW 20 - 30
Friday Night SW 20 - 30
Hurricane Ridge Direction - Speed
Thursday Afternoon SSE 25 - 35
Thursday Night SSE 25 - 35
Friday Morning SW 25 - 35
Friday Afternoon SW 25 - 35
Friday Night SW 15 - 25
Mt. Baker Direction - Speed
Thursday Afternoon SSE 15 - 25
Thursday Night SSE 20 - 30
Friday Morning SSW 20 - 30
Friday Afternoon SW 20 - 30
Friday Night SW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Thursday Afternoon SSE 10 - 20
Thursday Night SSE 20 - 30
Friday Morning SW 15 - 25
Friday Afternoon SW 20 - 30
Friday Night SW 15 - 25
Mt. Rainier Direction - Speed
Thursday Afternoon --- -
Thursday Night --- -
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Mt. Hood Direction - Speed
Thursday Afternoon SSE 10 - 20
Thursday Night SSE 20 - 30
Friday Morning SW 15 - 25
Friday Afternoon SW 20 - 30
Friday Night SW 20 - 30

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
Thursday Afternoon SSW 20 - 30 SSW 15 - 25 SSW 20 - 30 --- - SSW 30 - 45
Thursday Night SSW 40 - 60 SSW 30 - 45 SSW 40 - 60 --- - SSW 40 - 60
Friday Morning SSW 30 - 45 SSW 30 - 45 SSW 30 - 45 --- - SSW 35 - 50
Friday Afternoon SW 30 - 45 SW 20 - 30 SW 30 - 45 --- - SW 30 - 45
Mt. Baker Direction - Speed
Thursday Afternoon SSW 20 - 30
Thursday Night SSW 40 - 60
Friday Morning SSW 30 - 45
Friday Afternoon SW 30 - 45
Friday Night SW 25 - 35
Washington Pass Direction - Speed
Thursday Afternoon SSW 15 - 25
Thursday Night SSW 30 - 45
Friday Morning SSW 30 - 45
Friday Afternoon SW 20 - 30
Friday Night SW 25 - 35
Stevens and Snoqualmie Pass Direction - Speed
Thursday Afternoon SSW 20 - 30
Thursday Night SSW 40 - 60
Friday Morning SSW 30 - 45
Friday Afternoon SW 30 - 45
Friday Night SW 25 - 35
Mt. Rainier Direction - Speed
Thursday Afternoon --- -
Thursday Night --- -
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Mt. Hood Direction - Speed
Thursday Afternoon SSW 30 - 45
Thursday Night SSW 40 - 60
Friday Morning SSW 35 - 50
Friday Afternoon SW 30 - 45
Friday Night SW 40 - 60

Extended Weather Synopsis for Thursday night through Thursday

A shortwave ridge and surface high pressure will move across the Northwest on Saturday. This will cause light showers seen mainly over the Cascade west slopes to decrease and end on Saturday.

An upper trough and front will dig from over the Northwest coastal waters SSE to California on Sunday and Monday. Therefore the main flow aloft and main precipitation should stay offshore and head to California during that period.

Extended Weather

Olympics, Washington Cascades, Mt Hood
Saturday

Light showers mainly over the west slopes of the Cascades decreasing and ending.

Sunday

Increasing clouds in the morning especially Olympics and south Cascades. Increasing light rain or snow in the afternoon and evening mainly Olympics and south Cascades.

Monday

Mostly light showers mainly Olympics and south Cascades.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Saturday Morning - Sunday Morning Snow Level 2000' - 4000' 200' - 4000' 3000' - 5000'
Mt. Baker Elevation
Saturday Morning - Sunday Morning Snow Level
2000' - 4000'
Sunday Afternoon - Monday Night Snow Level
3000' - 5000'
Snoqualmie Pass Elevation
Saturday Morning - Sunday Morning Snow Level
200' - 4000'
Sunday Afternoon - Monday Night Snow Level
3000' - 5000'
Mt. Hood Elevation
Saturday Morning - Sunday Morning Snow Level
3000' - 5000'
Sunday Afternoon - Monday Night Snow Level
4000' - 6000'

* 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 Mar 23, 2017

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.