Issued: 2:24 PM PST Thursday, March 6, 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 Thursday & Tuesday

A deep low pressure system continues to track toward Vancouver Island this afternoon with the occluded front passing through the Cascades at 200 PM. Steady precipitation should exit to over the east slopes later this afternoon with moderate to locally heavy showers for the west slopes should follow behind the front in westerly flow this evening and ease into Friday morning. Snow levels should hang near 4000-5000 feet today and tonight.  

Light showers diminish further through Friday morning and a relatively dry period should take hold through Friday night with gradually warming temperatures Friday afternoon and Friday night as shortwave upper level ridging moves over the area. Partial clearing especially for the east slopes of the Cascades and Mt. Hood is likely during this period as well.  

Weather Forecast

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

Moderate to occasionally heavy rain and snow showers. 

Thursday Night - Friday Morning

Light rain and snow showers.  

East slopes of the Washington Cascades
Thursday Afternoon - Evening

Moderate rain and snow showers. 

Thursday Night - Friday Morning

Light rain and snow showers.  

Mt. Hood Area
Thursday Afternoon - Evening

Moderate to occasionally heavy rain and snow showers. 

Thursday Night - Friday Morning

Light rain and snow showers.  

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' ' ' ' ' 4500' ' 4500'
Thursday Night - Friday Mid-day Snow Level 4000' ' ' ' ' 4000' ' 4500'
Hurricane Ridge Elevation
Thursday Afternoon Snow Level
4500'
Thursday Night - Friday Mid-day Snow Level
4000'
Friday Afternoon - Friday Night Snow Level
5000'
(Easterly Flow *)
Mt. Baker Elevation
Thursday Afternoon Snow Level
'
Thursday Night - Friday Mid-day Snow Level
'
Friday Afternoon - Friday Night Snow Level
'
(Easterly Flow *)
Washington Pass Elevation
Thursday Afternoon Snow Level
'
Thursday Night - Friday Mid-day Snow Level
'
Friday Afternoon - Friday Night Snow Level
'
(Easterly Flow *)
Leavenworth Elevation
Thursday Afternoon Snow Level
'
Thursday Night - Friday Mid-day Snow Level
'
Friday Afternoon - Friday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Thursday Afternoon Snow Level
'
Thursday Night - Friday Mid-day Snow Level
'
Friday Afternoon - Friday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Thursday Afternoon Snow Level
4500'
Thursday Night - Friday Mid-day Snow Level
4000'
Friday Afternoon - Friday Night Snow Level
4500'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Thursday Afternoon Snow Level
'
Thursday Night - Friday Mid-day Snow Level
'
Friday Afternoon - Friday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Thursday Afternoon Snow Level
4500'
Thursday Night - Friday Mid-day Snow Level
4500'
Friday Afternoon - Friday Night Snow Level
6000'
(Easterly Flow *)

* 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

Tuesday Tuesday
Hurricane Ridge 0 - 1.00 LT 0.10
Mt Baker Ski Area 1.50 - 2.00 LT 0.25
Washington Pass 0 - 1.00 LT 0.10
Stevens Pass 1.00 - 1.50 LT 0.10
Snoqualmie Pass 0 - 1.50 LT 0.10
Mission Ridge 0.25 - 0.50 LT 0.10
Crystal Mt 1.00 - 1.50 LT 0.10
Paradise 0 - 1.50 LT 0.10
White Pass 0 - 0.75 LT 0.10
Mt Hood Meadows 1.00 - 1.50 LT 0.10
0 - 1.50 LT 0.10

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Thursday Afternoon - Thursday Evening W 25 - 35 --- - W 20 - 35 --- - WSW 20 - 30
Thursday Night - Friday Morning SW 10 - 20 --- - W 10 - 20 --- - W 10 - 20
Hurricane Ridge Elevation
Thursday Afternoon - Thursday Evening W 25 - 35
Thursday Night - Friday Morning SW 10 - 20
Friday Afternoon - Friday Night SW 5 - 15
Mt. Baker Elevation
Thursday Afternoon - Thursday Evening --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Stevens and Snoqualmie Pass Elevation
Thursday Afternoon - Thursday Evening W 20 - 35
Thursday Night - Friday Morning W 10 - 20
Friday Afternoon - Friday Night SW 0 - 10
Mt. Rainier Elevation
Thursday Afternoon - Thursday Evening --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Mt. Hood Elevation
Thursday Afternoon - Thursday Evening WSW 20 - 30
Thursday Night - Friday Morning W 10 - 20
Friday Afternoon - Friday Night S 0 - 10
Hurricane Ridge Direction - Speed
Thursday Afternoon - Thursday Evening W 25 - 35
Thursday Night - Friday Morning SW 10 - 20
Friday Afternoon - Friday Night SW 5 - 15
Mt. Baker Direction - Speed
Thursday Afternoon - Thursday Evening --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Thursday Afternoon - Thursday Evening W 20 - 35
Thursday Night - Friday Morning W 10 - 20
Friday Afternoon - Friday Night SW 0 - 10
Mt. Rainier Direction - Speed
Thursday Afternoon - Thursday Evening --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Mt. Hood Direction - Speed
Thursday Afternoon - Thursday Evening WSW 20 - 30
Thursday Night - Friday Morning W 10 - 20
Friday Afternoon - Friday Night S 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
Thursday Afternoon --- - --- - WSW 45 - 55 --- - W 45 - 55
Thursday Night - Friday Morning --- - --- - NW 25 - 35 --- - NW 30 - 45
Mt. Baker Direction - Speed
Thursday Afternoon --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Washington Pass Direction - Speed
Thursday Afternoon --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Thursday Afternoon WSW 45 - 55
Thursday Night - Friday Morning NW 25 - 35
Friday Afternoon - Friday Night SW 15 - 30
Mt. Rainier Direction - Speed
Thursday Afternoon --- -
Thursday Night - Friday Morning --- -
Friday Afternoon - Friday Night --- -
Mt. Hood Direction - Speed
Thursday Afternoon W 45 - 55
Thursday Night - Friday Morning NW 30 - 45
Friday Afternoon - Friday Night SW 15 - 30

Extended Weather Synopsis for Tuesday night through Tuesday

A strong frontal system extending from the NE Pacific and entraining a fair bit of moisture should begin to sag southeast from British Columbia to the PNW on Saturday and flatten the upper level ridge over the area. Some forecast models slow down this system about 6 hours from the latest GFS model that continues to show heavy rain and snow beginning in the north Cascades and Olympics Saturday afternoon...and sagging down over the south Washington Cascades and Mt. Hood area Saturday night. Quite a bit of warm air should be pumped into the region out ahead of the front...with snow levels pushing 7000-9000 feet Saturday night. Gradual cooling and showers should follow the frontal passage on Sunday.  Another shortwave rounding the same upper level trough over the area should pass through on Monday with more moderate snow levels and light to moderate rain and snow showers.    

Extended Weather

Olympics, Washington Cascades and Mt. Hood Area
Saturday Morning

Cloudy with light rain and snow developing north Washington Cascades and Olympics.  Mild. 

Saturday Afternoon

Moderate to heavy rain and snow Olympics, central and north Washington Cascades.  Light to moderate rain and snow developing south Washington Cascades and Mt. Hood area.  Continued warming. 

Saturday Night

Stormy with moderate to heavy rain and snow.  Mild. 

Sunday - Monday

Light to moderate rain and snow showers.  Gradual cooling trend Sunday through Monday. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Saturday Morning Snow Level ' - ' 4500' - 5500' 6000' - 7000' *
Saturday Afternoon - Sunday Morning Snow Level ' - ' 6000' - 8000' 7500' - 9000'
Sunday Afternoon Snow Level ' - ' 3000' - 4000' 3500' - 4500'
Mt. Baker Elevation
Saturday Morning Snow Level
' - '
(Easterly Flow *)
Saturday Afternoon - Sunday Morning Snow Level
' - '
Sunday Afternoon Snow Level
' - '
Sunday Night - Monday Snow Level
' - '
Snoqualmie Pass Elevation
Saturday Morning Snow Level
4500' - 5500'
(Easterly Flow *)
Saturday Afternoon - Sunday Morning Snow Level
6000' - 8000'
Sunday Afternoon Snow Level
3000' - 4000'
Sunday Night - Monday Snow Level
3500' - 4500'
Mt. Hood Elevation
Saturday Morning Snow Level
6000' - 7000'
(Easterly Flow *)
Saturday Afternoon - Sunday Morning Snow Level
7500' - 9000'
Sunday Afternoon Snow Level
3500' - 4500'
Sunday Night - Monday Snow Level
3500' - 4500'

* 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 6, 2014

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