Issued: 2:43 PM PST Saturday, February 4, 2017
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 Saturday & Wednesday

An active weekend is in store for the PNW as an upper level low in the northerly branch of the jet stream sinks off the B.C./WA coast and merges with the southern branch of the jet currently aimed into northern CA/southern OR. Frontal bands will rotate through the PNW today associated with the upper level low offshore. The heavier periods of precipitation look to be this morning followed by an early afternoon lull for the Cascades and Mt. Hood. Another frontal band will pass through late afternoon/early evening for renewed moderate precipitation. Slight warming has been seen throughout the Cascades today but easterly flow will keep the lower Passes and east slopes locally cooler today, with a brief bump up in snow levels expected with a switch to westerly flow early this evening to about 3500-4000 feet. Snow levels in the Crystal/Paradise area should hover around 4500 feet today. 

Showers should slightly decrease late overnight becoming light by Sunday morning except for the Mt. Hood area. By Sunday afternoon southern stream moisture should bring another round of snow, with heavier amounts for the south Washington Cascades (equally affecting the west and east slopes) and Mt. Hood. The bulk of the moisture from this system will miss the Olympics and north Cascades. Arctic air will begin to move in from the north Sunday night and snow levels should begin to plummet.

Weather Forecast

Olympics
Saturday Afternoon - Saturday Evening

Light to moderate rain and snow, tapering down late morning before increasing again in the afternoon.  

Saturday Night - Sunday Morning

Light snow showers. Cooler. 

Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Saturday Afternoon - Saturday Evening

Moderate rain and snow. Brief warming lower elevations of Passes late afternoon and early evening. 

Saturday Night - Sunday Morning

Light to moderate snow showers. Cooler. 

East slopes of the Washington Cascades
Saturday

Light to occasionally moderate rain and snow, tapering down mid-day before increasing again late afternoon. Slight warming trend aloft. 

Saturday Evening

Light to occasionally moderate rain and snow with brief warming lower elevations. 

Saturday Night - Sunday Morning

Light snow showers. Cooler. 

Mt. Hood Area
Saturday Afternoon - Saturday Evening

Light to occasionally moderate rain and snow. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Saturday Afternoon Snow Level * 2500' 3000' 3500' ' ' 3000' ' 4500'
Saturday Evening Snow Level 2000' 2500' 2500' ' ' 3500' ' 4000'
Saturday Night - Sunday Morning Snow Level 1000' 1000' 1000' ' ' 1500' ' 3500'
Sunday Afternoon Snow Level 1000' 500' 1000' ' ' 1500' ' 4000'
Hurricane Ridge Elevation
Saturday Afternoon Snow Level
2500'
(Easterly Flow *)
Saturday Evening Snow Level
2000'
Saturday Night - Sunday Morning Snow Level
1000'
Sunday Afternoon Snow Level
1000'
Sunday Night Snow Level
0'
Mt. Baker Elevation
Saturday Afternoon Snow Level
3000'
(Easterly Flow *)
Saturday Evening Snow Level
2500'
Saturday Night - Sunday Morning Snow Level
1000'
Sunday Afternoon Snow Level
500'
Sunday Night Snow Level
0'
Washington Pass Elevation
Saturday Afternoon Snow Level
3500'
(Easterly Flow *)
Saturday Evening Snow Level
2500'
Saturday Night - Sunday Morning Snow Level
1000'
Sunday Afternoon Snow Level
1000'
Sunday Night Snow Level
0'
Leavenworth Elevation
Saturday Afternoon Snow Level
'
(Easterly Flow *)
Saturday Evening Snow Level
'
Saturday Night - Sunday Morning Snow Level
'
Sunday Afternoon Snow Level
'
Sunday Night Snow Level
'
Stevens Pass Elevation
Saturday Afternoon Snow Level
'
(Easterly Flow *)
Saturday Evening Snow Level
'
Saturday Night - Sunday Morning Snow Level
'
Sunday Afternoon Snow Level
'
Sunday Night Snow Level
'
Snoqualmie Pass Elevation
Saturday Afternoon Snow Level
3000'
(Easterly Flow *)
Saturday Evening Snow Level
3500'
Saturday Night - Sunday Morning Snow Level
1500'
Sunday Afternoon Snow Level
1500'
Sunday Night Snow Level
500'
Mt. Rainier & Crystal Elevation
Saturday Afternoon Snow Level
'
(Easterly Flow *)
Saturday Evening Snow Level
'
Saturday Night - Sunday Morning Snow Level
'
Sunday Afternoon Snow Level
'
Sunday Night Snow Level
'
Mt. Hood Elevation
Saturday Afternoon Snow Level
4500'
(Easterly Flow *)
Saturday Evening Snow Level
4000'
Saturday Night - Sunday Morning Snow Level
3500'
Sunday Afternoon Snow Level
4000'
Sunday Night Snow Level
2000'

* 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

Wednesday Wednesday
Hurricane Ridge 0 - 0.50 LT 0.25
Mt Baker Ski Area 1.00 - 1.50 LT 0.25
Washington Pass 0 - 0.75 0.25 - 0.50
Stevens Pass 0 - 1.00 0.50 - 0.75
Snoqualmie Pass 0 - 1.50 0.75 - 1.00
Mission Ridge LT 0.25 0 - 0.75
Crystal Mt 0 - 1.00 0 - 1.00
Paradise 1.50 - 2.00 1.00 - 1.50
White Pass 0 - 1.00 1.00 - 1.50
Mt Hood Meadows 0 - 1.50 1.50 - 2.00
0 - 2.00 0 - 2.00

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Saturday Afternoon S 10 - 20 S 10 - 20 S 15 - 25 --- - SW 20 - 30
Saturday Evening SW 15 - 25 SW 15 - 25 SW 15 - 30 --- - SW 20 - 30
Saturday Night - Sunday Morning S 0 - 10 S 0 - 10 SW 5 - 15 --- - SW 5 - 15
Hurricane Ridge Elevation
Saturday Afternoon S 10 - 20
Saturday Evening SW 15 - 25
Saturday Night - Sunday Morning S 0 - 10
Sunday Afternoon - Sunday Night ENE 5 - 15
Mt. Baker Elevation
Saturday Afternoon S 10 - 20
Saturday Evening SW 15 - 25
Saturday Night - Sunday Morning S 0 - 10
Sunday Afternoon - Sunday Night NE 5 - 15
Stevens and Snoqualmie Pass Elevation
Saturday Afternoon S 15 - 25
Saturday Evening SW 15 - 30
Saturday Night - Sunday Morning SW 5 - 15
Sunday Afternoon - Sunday Night E 0 - 10
Mt. Rainier Elevation
Saturday Afternoon --- -
Saturday Evening --- -
Saturday Night - Sunday Morning --- -
Sunday Afternoon - Sunday Night --- -
Mt. Hood Elevation
Saturday Afternoon SW 20 - 30
Saturday Evening SW 20 - 30
Saturday Night - Sunday Morning SW 5 - 15
Sunday Afternoon - Sunday Night SW 15 - 25
Hurricane Ridge Direction - Speed
Saturday Afternoon S 10 - 20
Saturday Evening SW 15 - 25
Saturday Night - Sunday Morning S 0 - 10
Sunday Afternoon - Sunday Night ENE 5 - 15
Mt. Baker Direction - Speed
Saturday Afternoon S 10 - 20
Saturday Evening SW 15 - 25
Saturday Night - Sunday Morning S 0 - 10
Sunday Afternoon - Sunday Night NE 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Saturday Afternoon S 15 - 25
Saturday Evening SW 15 - 30
Saturday Night - Sunday Morning SW 5 - 15
Sunday Afternoon - Sunday Night E 0 - 10
Mt. Rainier Direction - Speed
Saturday Afternoon --- -
Saturday Evening --- -
Saturday Night - Sunday Morning --- -
Sunday Afternoon - Sunday Night --- -
Mt. Hood Direction - Speed
Saturday Afternoon SW 20 - 30
Saturday Evening SW 20 - 30
Saturday Night - Sunday Morning SW 5 - 15
Sunday Afternoon - Sunday 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
Saturday Afternoon SW 20 - 30 SW 25 - 35 SW 35 - 45 --- - SW 50 - 60
Saturday Night - Sunday Morning SW 20 - 30 SW 45 - 55 SW 45 - 60 --- - SW 50 - 60
Sunday Afternoon W 0 - 10 SW 5 - 15 WSW 25 - 35 --- - SW 60 - 70
Mt. Baker Direction - Speed
Saturday Afternoon SW 20 - 30
Saturday Night - Sunday Morning SW 20 - 30
Sunday Afternoon W 0 - 10
Sunday Night S 0 - 10
Washington Pass Direction - Speed
Saturday Afternoon SW 25 - 35
Saturday Night - Sunday Morning SW 45 - 55
Sunday Afternoon SW 5 - 15
Sunday Night S 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Saturday Afternoon SW 35 - 45
Saturday Night - Sunday Morning SW 45 - 60
Sunday Afternoon WSW 25 - 35
Sunday Night SW 15 - 30
Mt. Rainier Direction - Speed
Saturday Afternoon --- -
Saturday Night - Sunday Morning --- -
Sunday Afternoon --- -
Sunday Night --- -
Mt. Hood Direction - Speed
Saturday Afternoon SW 50 - 60
Saturday Night - Sunday Morning SW 50 - 60
Sunday Afternoon SW 60 - 70
Sunday Night SW 50 - 60

Extended Weather Synopsis for Wednesday night through Wednesday

Light to moderate snow will linger for the south and central Washington Cascades and Mt. Hood through Monday morning before transitioning to showers that favor the west slope of the Cascades in the afternoon.  An elongated trough will stretch out over southern B.C. turning the flow more westerly and directing a few more impulses into the region through Tuesday with low snow levels. An upper level ridge building offshore on Tuesday should move over the coast on Wednesday, bringing about a brief break in the active pattern. 

Extended Weather

Olympics, Washington Cascades and Mt. Hood
Monday Morning

Periods of light snow north Cascades. Light to moderate snow central Cascades. Moderate snow south Cascades. 

Monday Afternoon - Tuesday

Light to occasionally moderate snow showers. 

Tuesday Night - Wednesday

Scattered snow showers tapering off Tuesday night and becoming partly to mostly cloudy on Wednesday. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Monday - Monday Night Snow Level 0' - 500' 0' - 500' 0' - 1000'
Mt. Baker Elevation
Monday - Monday Night Snow Level
0' - 500'
Tuesday - Wednesday Snow Level
0' - 500'
Snoqualmie Pass Elevation
Monday - Monday Night Snow Level
0' - 500'
Tuesday - Wednesday Snow Level
0' - 1000'
Mt. Hood Elevation
Monday - Monday Night Snow Level
0' - 1000'
Tuesday - Wednesday Snow Level
1500' - 2500'

* 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 Feb 4, 2017

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