Issued: 7:21 AM PST Tuesday, February 18, 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 Tuesday & Friday

It's not deja vu, yet another strong Pacific frontal system in progressive westerly flow has already begun to spread steady rain and snow over the Olympic Peninsula and the north and central Washington Cascades this morning.  Precipitation will become heavy in the late morning for the Cascades and by early afternoon over Mt. Hood.  An occluded front extending from a parent low off the central British Columbia coast will pass through the Cascades mid-day. Snow levels should gradually rise this morning out ahead of the front. Easterly flow through the Cascade passes should initially insulate them from the warmer air, but a switch to westerly flow post-frontal should allow snow levels to temporarily bump up to nearly 4000 feet near Snoqualmie and 4500 feet near White Pass through the afternoon hours.  Intense precipitation rates, with snowfall over an inch an hour is expected this afternoon.  Winds will increase today as well...creating stormy conditions in the afternoon. 

Showers and a steep cooling trend should be seen overnight as snow levels fall to 1000-2000 feet by midnight.  Forecast models again indicated a Puget Sound Convergence Zone near Stevens Pass forming this evening and continuing overnight producing locally heavier accumulations. Showers should continue on Wednesday...with an upper level feature enhancing showers during the day. Another Pacific frontal system should impact the PNW Wednesday night...with steady precipitation increasing late Wednesday night.  There should be less warming with this system.  However, the European forecast model is slower with this system and does not spread steady precipitation over the area until Thursday morning. 

Weather Forecast

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

Moderate rain and snow spreading from the Olympics and north Cascades to the central and south Washington Cascades by late morning.  Winds increasing.  Gradual warming. 

Tuesday Afternoon

Stormy with moderate to heavy rain and snow and snow levels becoming free-air snow levels in the Cascade Passes early afternoon. 

Tuesday Night

Light to moderate snow showers....occasionally heavy near Stevens Pass and a potential Puget Sound Convergence Zone. 

Wednesday - Wednesday Evening

Light to moderate snow showers.  

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

Moderate rain and snow spreading from the north Cascades to the central and south Washington Cascades by late morning.  Winds increasing.  Gradual warming. 

Tuesday Afternoon

Stormy with moderate to heavy rain and snow and snow levels becoming free-air snow levels in the Cascade Passes early afternoon. 

Tuesday Night

Light to moderate snow showers....occasionally heavy near Stevens Pass and a potential Puget Sound Convergence Zone. 

Wednesday - Wednesday Evening

Light to occasionally moderate snow showers.  

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

Cloudy with moderate rain and snow developing by mid-day.  Winds increasing.  Gradual warming. 

Tuesday Afternoon - Tuesday Evening

Stormy with moderate to heavy rain and snow becoming moderate showers in the evening. 

Tuesday Night

Light to moderate snow showers. 

Wednesday - Wednesday Evening

Light to occasionally moderate snow showers.  

Snow/Freezing Level (ft)

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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Morning SW 20 - 30 --- - SW 15 - 25 --- - SW 30 - 40
Tuesday Mid-day SW 45 - 55 --- - SSW 25 - 40 --- - SW 35 - 45
Tuesday Afternoon WSW 25 - 35 --- - W 30 - 40 --- - SW 40 - 50
Tuesday Night - Wednesday Mid-day W 25 - 35 --- - W 30 - 40 --- - W 25 - 35
Wednesday Afternoon - Wednesday Evening SW 15 - 25 --- - W 20 - 30 --- - W 20 - 30
Hurricane Ridge Elevation
Tuesday Morning SW 20 - 30
Tuesday Mid-day SW 45 - 55
Tuesday Afternoon WSW 25 - 35
Tuesday Night - Wednesday Mid-day W 25 - 35
Wednesday Afternoon - Wednesday Evening SW 15 - 25
Wednesday Night W 25 - 35
Mt. Baker Elevation
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Mid-day --- -
Wednesday Afternoon - Wednesday Evening --- -
Wednesday Night --- -
Stevens and Snoqualmie Pass Elevation
Tuesday Morning SW 15 - 25
Tuesday Mid-day SSW 25 - 40
Tuesday Afternoon W 30 - 40
Tuesday Night - Wednesday Mid-day W 30 - 40
Wednesday Afternoon - Wednesday Evening W 20 - 30
Wednesday Night WSW 35 - 45
Mt. Rainier Elevation
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Mid-day --- -
Wednesday Afternoon - Wednesday Evening --- -
Wednesday Night --- -
Mt. Hood Elevation
Tuesday Morning SW 30 - 40
Tuesday Mid-day SW 35 - 45
Tuesday Afternoon SW 40 - 50
Tuesday Night - Wednesday Mid-day W 25 - 35
Wednesday Afternoon - Wednesday Evening W 20 - 30
Wednesday Night SW 40 - 50
Hurricane Ridge Direction - Speed
Tuesday Morning SW 20 - 30
Tuesday Mid-day SW 45 - 55
Tuesday Afternoon WSW 25 - 35
Tuesday Night - Wednesday Mid-day W 25 - 35
Wednesday Afternoon - Wednesday Evening SW 15 - 25
Wednesday Night W 25 - 35
Mt. Baker Direction - Speed
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Mid-day --- -
Wednesday Afternoon - Wednesday Evening --- -
Wednesday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning SW 15 - 25
Tuesday Mid-day SSW 25 - 40
Tuesday Afternoon W 30 - 40
Tuesday Night - Wednesday Mid-day W 30 - 40
Wednesday Afternoon - Wednesday Evening W 20 - 30
Wednesday Night WSW 35 - 45
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Mid-day --- -
Wednesday Afternoon - Wednesday Evening --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning SW 30 - 40
Tuesday Mid-day SW 35 - 45
Tuesday Afternoon SW 40 - 50
Tuesday Night - Wednesday Mid-day W 25 - 35
Wednesday Afternoon - Wednesday Evening W 20 - 30
Wednesday Night SW 40 - 50

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
Tuesday Morning --- - --- - WSW 35 - 45 --- - W 40 - 50
Tuesday Mid-day --- - --- - SW 65 - 75 --- - WSW 40 - 50
Tuesday Afternoon --- - --- - WSW 45 - 55 --- - W 55 - 65
Tuesday Night - Wednesday Evening --- - --- - WNW 35 - 45 --- - WNW 35 - 45
Mt. Baker Direction - Speed
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Evening --- -
Wednesday Night --- -
Washington Pass Direction - Speed
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Evening --- -
Wednesday Night --- -
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning WSW 35 - 45
Tuesday Mid-day SW 65 - 75
Tuesday Afternoon WSW 45 - 55
Tuesday Night - Wednesday Evening WNW 35 - 45
Wednesday Night WNW 45 - 55
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Mid-day --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Evening --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning W 40 - 50
Tuesday Mid-day WSW 40 - 50
Tuesday Afternoon W 55 - 65
Tuesday Night - Wednesday Evening WNW 35 - 45
Wednesday Night WNW 50 - 60

Extended Weather Synopsis for Friday night through Friday

The jet stream will remain over Washington state Thursday and Thursday night with Northwest flow aloft and good orographics and upslope flow producing moderate to occasionally heavy snow showers especially over the west slopes of the Cascades.  Snow levels should remain quite cool with breezy to windy conditions. Shower should taper off on Friday. 

A break in the very active weather pattern begins on Friday. An upper level ridge builds out toward 140 W.  A weak weather system should slide over the top of the ridge and into western Washington late Friday night and Saturday.  Mt. Hood may see little precipitation from this system. Snow levels should moderate on Saturday. 

Extended Weather

Olympics and Washington Cascades
Thursday - Thursday Night

Moderate to occasionally heavy snow showers west slopes and breezy.  

Friday Morning

Light to moderate snow showers tapering down. 

Friday Afternoon - Friday Evening

Scattered light snow showers with partial clearing. 

Friday Night - Saturday

Light to moderate rain and snow at times with a gradual warming trend.  

East slopes of the Washington Cascades
Thursday - Thursday Night

Moderate snow showers...heaviest near the crest and breezy.  

Friday Morning

Partly cloudy with scattered snow showers. 

Friday Afternoon - Friday Evening

Partly cloudy. 

Friday Night - Saturday

Light rain and snow at times with a gradual warming trend.  

Mt. Hood Area
Thursday - Thursday Night

Moderate snow showers and breezy.  

Friday Morning

Light to moderate snow showers tapering down. 

Friday Afternoon - Friday Evening

Scattered light snow showers with partial clearing. 

Friday Night - Saturday

Mostly cloudy with periods of light rain and snow with a gradual warming trend.  

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Thursday Snow Level ' - ' 1500' - 2500' 2500' - 3500'
Thursday Night - Friday Mid-day Snow Level ' - ' 500' - 1500' 1000' - 200'
Friday Afternoon - Friday Night Snow Level ' - ' 1000' - 2000' 2000' - 3000'
Mt. Baker Elevation
Thursday Snow Level
' - '
Thursday Night - Friday Mid-day Snow Level
' - '
Friday Afternoon - Friday Night Snow Level
' - '
Saturday Snow Level
' - '
Snoqualmie Pass Elevation
Thursday Snow Level
1500' - 2500'
Thursday Night - Friday Mid-day Snow Level
500' - 1500'
Friday Afternoon - Friday Night Snow Level
1000' - 2000'
Saturday Snow Level
2000' - 3000'
Mt. Hood Elevation
Thursday Snow Level
2500' - 3500'
Thursday Night - Friday Mid-day Snow Level
1000' - 200'
Friday Afternoon - Friday Night Snow Level
2000' - 3000'
Saturday 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 Feb 17, 2014

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