Issued: 8:02 AM PST Thursday, February 5, 2015
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 Thursday & Friday

The parade of fronts in moist and mild southwesterly flow has begun this morning with warm frontal moisture draped over Washington. Expect heavy rain and snow for north Cascades and more moderate amounts of precipitation further south.  A warming trend will also occur today, with a front passing through the Cascades in the early afternoon and switching the pass level winds to westerly.  Snowfall at Stevens Pass and mixed precipitation at Snoqualmie should become all rain by late morning/mid-day as warm air surges into the area. 

The next wave developing frontal system will lift through Thursday night, again with Mt. Baker receiving the most and Mt. Hood the least precipitation. SW winds near and above treeline will vary between moderate and strong throughout the short term. 

The jet stream will begin to drop south on Friday and a weaker frontal system will pass through during the day with most of the energy and precipitation passing into N. California. Some cooling will take place aloft... lowering snow levels a bit but still well above pass level Friday night and Saturday. 

Weather Forecast

Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Thursday Morning - Thursday Mid-day

Moderate rain and snow, except heavy Mt. Baker area.  Mixed precipitation possible passes.  Warming trend. 

Thursday Afternoon

Light to moderate rain and snow showers. Milder. 

Thursday Night - Friday

Light to moderate rain and snow, except heavy Mt. Baker area.  

East slopes of the Washington Cascades
Thursday Morning - Thursday Mid-day

Light to moderate rain and snow, except occasionally heavy northeast Cascades. Warming trend. 

Thursday Afternoon

Light rain and snow showers. Milder. 

Thursday Night - Friday

Light rain and snow, except occasionally moderate northeast Cascades.  

Mt. Hood Area
Thursday - Thursday

Light to occasionally moderate rain and snow.  Warming trend. 

Thursday Night - Friday

Light 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
Thursday Morning Snow Level * 7000' 5000' 4000' ' ' 5500' ' 7000'
Thursday Mid-day - Thursday Night Snow Level 7000' 6500' 6500' ' ' 7000' ' 8000'
Friday Snow Level 6500' 6500' 6000' ' ' 6500' ' 7500'
Hurricane Ridge Elevation
Thursday Morning Snow Level
7000'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
7000'
Friday Snow Level
6500'
Friday Night Snow Level
5500'
Mt. Baker Elevation
Thursday Morning Snow Level
5000'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
6500'
Friday Snow Level
6500'
Friday Night Snow Level
5000'
Washington Pass Elevation
Thursday Morning Snow Level
4000'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
6500'
Friday Snow Level
6000'
Friday Night Snow Level
5000'
Leavenworth Elevation
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
'
Friday Snow Level
'
Friday Night Snow Level
'
Stevens Pass Elevation
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
'
Friday Snow Level
'
Friday Night Snow Level
'
Snoqualmie Pass Elevation
Thursday Morning Snow Level
5500'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
7000'
Friday Snow Level
6500'
Friday Night Snow Level
5000'
Mt. Rainier & Crystal Elevation
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
'
Friday Snow Level
'
Friday Night Snow Level
'
Mt. Hood Elevation
Thursday Morning Snow Level
7000'
(Easterly Flow *)
Thursday Mid-day - Thursday Night Snow Level
8000'
Friday Snow Level
7500'
Friday Night Snow Level
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.

Precipitation Forecast

Friday Friday
Hurricane Ridge 1.00 - 1.50 0 - 1.00
Mt Baker Ski Area 3.00 - 4.00 2.00 - 3.00
Washington Pass 1.50 - 2.00 0 - 1.00
Stevens Pass 1.00 - 1.50 0.75 - 1.00
Snoqualmie Pass 1.50 - 2.00 1.00 - 1.50
Mission Ridge 0 - 0.50 0.25 - 0.50
Crystal Mt 1.00 - 1.50 0 - 0.75
Paradise 0 - 2.00 1.00 - 1.50
White Pass 1.00 - 1.50 0 - 1.00
Mt Hood Meadows 0 - 0.75 0 - 1.00
0 - 0.75 0 - 1.00

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Thursday - Morning S 25 - 35 SSW 15 - 25 SE 15 - 25 --- - SSW 15 - 25
Thursday Afternoon SW 20 - 30 SW 15 - 25 SW 25 - 35 --- - SW 20 - 30
Thursday Night - Friday SW 25 - 40 SSW 25 - 35 SW 25 - 35 --- - SW 35 - 45
Hurricane Ridge Elevation
Thursday - Morning S 25 - 35
Thursday Afternoon SW 20 - 30
Thursday Night - Friday SW 25 - 40
Friday Night SW 25 - 35
Mt. Baker Elevation
Thursday - Morning SSW 15 - 25
Thursday Afternoon SW 15 - 25
Thursday Night - Friday SSW 25 - 35
Friday Night SW 20 - 30
Stevens and Snoqualmie Pass Elevation
Thursday - Morning SE 15 - 25
Thursday Afternoon SW 25 - 35
Thursday Night - Friday SW 25 - 35
Friday Night SW 15 - 25
Mt. Rainier Elevation
Thursday - Morning --- -
Thursday Afternoon --- -
Thursday Night - Friday --- -
Friday Night --- -
Mt. Hood Elevation
Thursday - Morning SSW 15 - 25
Thursday Afternoon SW 20 - 30
Thursday Night - Friday SW 35 - 45
Friday Night SW 15 - 25
Hurricane Ridge Direction - Speed
Thursday - Morning S 25 - 35
Thursday Afternoon SW 20 - 30
Thursday Night - Friday SW 25 - 40
Friday Night SW 25 - 35
Mt. Baker Direction - Speed
Thursday - Morning SSW 15 - 25
Thursday Afternoon SW 15 - 25
Thursday Night - Friday SSW 25 - 35
Friday Night SW 20 - 30
Stevens and Snoqualmie Pass Direction - Speed
Thursday - Morning SE 15 - 25
Thursday Afternoon SW 25 - 35
Thursday Night - Friday SW 25 - 35
Friday Night SW 15 - 25
Mt. Rainier Direction - Speed
Thursday - Morning --- -
Thursday Afternoon --- -
Thursday Night - Friday --- -
Friday Night --- -
Mt. Hood Direction - Speed
Thursday - Morning SSW 15 - 25
Thursday Afternoon SW 20 - 30
Thursday Night - Friday SW 35 - 45
Friday 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
Thursday - Thursday Evening SW 30 - 40 SW 35 - 50 SW 40 - 50 --- - SW 50 - 65
Thursday Night - Friday Morning SW 45 - 55 SW 45 - 55 SW 50 - 60 --- - SW 60 - 70
Friday Afternoon SW 40 - 50 SW 35 - 45 SW 50 - 60 --- - SW 50 - 60
Mt. Baker Direction - Speed
Thursday - Thursday Evening SW 30 - 40
Thursday Night - Friday Morning SW 45 - 55
Friday Afternoon SW 40 - 50
Friday Night SW 35 - 45
Washington Pass Direction - Speed
Thursday - Thursday Evening SW 35 - 50
Thursday Night - Friday Morning SW 45 - 55
Friday Afternoon SW 35 - 45
Friday Night WSW 40 - 50
Stevens and Snoqualmie Pass Direction - Speed
Thursday - Thursday Evening SW 40 - 50
Thursday Night - Friday Morning SW 50 - 60
Friday Afternoon SW 50 - 60
Friday Night WSW 40 - 50
Mt. Rainier Direction - Speed
Thursday - Thursday Evening --- -
Thursday Night - Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Mt. Hood Direction - Speed
Thursday - Thursday Evening SW 50 - 65
Thursday Night - Friday Morning SW 60 - 70
Friday Afternoon SW 50 - 60
Friday Night SW 25 - 35

Extended Weather Synopsis for Friday night through Friday

The active pattern will continue on Saturday with another ill-defined system rotating through in SW flow aloft.  There may actually be a 12-24 hour break between systems before the next one arrives Sunday afternoon.  Snow levels should mainly oscillate between 5000-6000 feet from the weekend through Monday for the WA Cascades. 

A stacked low offshore should move the area later Monday, keeping light to moderate showers in the forecast.  

Extended Weather

Olympics, Washington Cascades and Mt. Hood Area
Saturday

Cloudy with light to moderate rain and snow showers. 

Saturday Night - Sunday Morning

Mostly cloudy with scattered light rain and snow showers. 

Sunday Afternoon - Sunday Night

Light to moderate rain and snow developing Mt. Hood mid-day and spreading north.  

Monday

Cloudy with light to occasionally moderate rain and snow showers. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Saturday - Sunday Morning Snow Level 4500' - 5500' 5000' - 6000' 5500' - 6500'
Sunday Afternoon Snow Level 4500' - 5500' 5500' - 7000' 7000' - 8000'
Mt. Baker Elevation
Saturday - Sunday Morning Snow Level
4500' - 5500'
Sunday Afternoon Snow Level
4500' - 5500'
Sunday Night - Monday Snow Level
5000' - 6000'
Snoqualmie Pass Elevation
Saturday - Sunday Morning Snow Level
5000' - 6000'
Sunday Afternoon Snow Level
5500' - 7000'
Sunday Night - Monday Snow Level
5500' - 6500'
Mt. Hood Elevation
Saturday - Sunday Morning Snow Level
5500' - 6500'
Sunday Afternoon Snow Level
7000' - 8000'
Sunday Night - Monday Snow Level
5500' - 6500'

* 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 1, 2015

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