Issued: 7:41 AM PST Wednesday, February 17, 2016
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 Wednesday & Saturday

A upper level low well offshore has spread areas of light warm frontal precipitation over the area this morning and should continue to do so throughout the day. The PNW will remain in the warm sector with generally mild snow levels. 

An occluded front will pass through this evening bringing a brief shot of moderate precipitation for the west slopes of the Cascades. Shower activity should decrease quickly overnight, except near Mt. Baker where moderate showers in post-frontal SW flow will continue through late tonight. Snow levels will lower behind the front to 3500-4000 feet. 

After a brief break in the action Thursday morning, the trailing upper trough and a weakening surface low off the Oregon/Washington coast will move inland during the afternoon. 

Forecast models suggestion a steep N-S precipitaiton gradient as the weakening low passes east of the Cascades through the late afternoon or early evening, with the potential for locally heavier snow amounts from Snoqualmie Pass south to Mt. Rainier. The passage of the low could also bring a quick increase in W-SW winds.  Lesser amounts are expected further north.  

Weather Forecast

Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Wednesday

Cloudy with periods of light rain and snow. Mild. 

Wednesday Night

Light to occasionally moderate rain and snow becoming showers late tonight. Cooling trend. 

Thursday Morning

Mostly cloudy with light rain and snow showers. 

Thursday Afternoon - Thursday Evening

Light to occasionally moderate showers north Cascades and Olympics. Moderate to occasionally heavy rain and snow showers central and south Cascades with increasing winds. 

Mt. Hood Area
Wednesday

Cloudy with periods of light rain and snow. Mild. 

Wednesday Night

Light to occasionally moderate rain and snow becoming light showers late tonight. Cooling trend. 

Thursday Morning

Mostly cloudy with light rain and snow showers. 

Thursday Afternoon - Thursday Evening

Moderate rain and snow showers with winds becoming strong in the afternoon. 

East slopes of the Washington Cascades
Wednesday

Cloudy with periods of very light rain and snow. Mild. 

Wednesday Night

Light rain and snow becoming mostly cloudy with scattered showers late tonight. Cooling trend. 

Thursday Morning

Mostly cloudy with isolated light rain and snow showers. 

Thursday Afternoon - Thursday Evening

Mostly cloudy with scattered light showers northeast Cascades. Light to moderate rain and snow showers central and south Cascades with increasing winds. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Wednesday Morning Snow Level * 6000' 5500' 4500' ' ' 6000' ' 6500'
Wednesday Afternoon Snow Level * 6000' 6000' 5500' ' ' 6000' ' 6500'
Wednesday Night Snow Level 4500' 4500' 4500' ' ' 5000' ' 5000'
Hurricane Ridge Elevation
Wednesday Morning Snow Level
6000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
6000'
(Easterly Flow *)
Wednesday Night Snow Level
4500'
Thursday - Thursday Evening Snow Level
4000'
Mt. Baker Elevation
Wednesday Morning Snow Level
5500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
6000'
(Easterly Flow *)
Wednesday Night Snow Level
4500'
Thursday - Thursday Evening Snow Level
3500'
Washington Pass Elevation
Wednesday Morning Snow Level
4500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
5500'
(Easterly Flow *)
Wednesday Night Snow Level
4500'
Thursday - Thursday Evening Snow Level
3500'
Leavenworth Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
Thursday - Thursday Evening Snow Level
'
Stevens Pass Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
Thursday - Thursday Evening Snow Level
'
Snoqualmie Pass Elevation
Wednesday Morning Snow Level
6000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
6000'
(Easterly Flow *)
Wednesday Night Snow Level
5000'
Thursday - Thursday Evening Snow Level
3500'
Mt. Rainier & Crystal Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
Thursday - Thursday Evening Snow Level
'
Mt. Hood Elevation
Wednesday Morning Snow Level
6500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
6500'
(Easterly Flow *)
Wednesday Night Snow Level
5000'
Thursday - Thursday Evening Snow Level
4000'

* 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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Wednesday Morning SSE 10 - 20 SE 10 - 20 ESE 10 - 20 --- - SE 5 - 15
Wednesday Afternoon S 15 - 25 SSE 5 - 15 ESE 5 - 15 --- - SE 5 - 15
Wednesday Night SW 15 - 25 SE 5 - 15 SW 15 - 25 --- - WSW 10 - 20
Thursday Morning S 10 - 20 S 10 - 20 S 15 - 30 --- - SW 20 - 30
Thursday Afternoon SW 5 - 15 S 5 - 15 ESE 5 - 15 --- - SW 30 - 50
Hurricane Ridge Elevation
Wednesday Morning SSE 10 - 20
Wednesday Afternoon S 15 - 25
Wednesday Night SW 15 - 25
Thursday Morning S 10 - 20
Thursday Afternoon SW 5 - 15
Thursday Night SW 15 - 25
Mt. Baker Elevation
Wednesday Morning SE 10 - 20
Wednesday Afternoon SSE 5 - 15
Wednesday Night SE 5 - 15
Thursday Morning S 10 - 20
Thursday Afternoon S 5 - 15
Thursday Night S 10 - 20
Stevens and Snoqualmie Pass Elevation
Wednesday Morning ESE 10 - 20
Wednesday Afternoon ESE 5 - 15
Wednesday Night SW 15 - 25
Thursday Morning S 15 - 30
Thursday Afternoon ESE 5 - 15
Thursday Night SW 20 - 40
Mt. Rainier Elevation
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Elevation
Wednesday Morning SE 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night WSW 10 - 20
Thursday Morning SW 20 - 30
Thursday Afternoon SW 30 - 50
Thursday Night WSW 25 - 40
Hurricane Ridge Direction - Speed
Wednesday Morning SSE 10 - 20
Wednesday Afternoon S 15 - 25
Wednesday Night SW 15 - 25
Thursday Morning S 10 - 20
Thursday Afternoon SW 5 - 15
Thursday Night SW 15 - 25
Mt. Baker Direction - Speed
Wednesday Morning SE 10 - 20
Wednesday Afternoon SSE 5 - 15
Wednesday Night SE 5 - 15
Thursday Morning S 10 - 20
Thursday Afternoon S 5 - 15
Thursday Night S 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning ESE 10 - 20
Wednesday Afternoon ESE 5 - 15
Wednesday Night SW 15 - 25
Thursday Morning S 15 - 30
Thursday Afternoon ESE 5 - 15
Thursday Night SW 20 - 40
Mt. Rainier Direction - Speed
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning SE 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night WSW 10 - 20
Thursday Morning SW 20 - 30
Thursday Afternoon SW 30 - 50
Thursday Night WSW 25 - 40

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
Wednesday SW 20 - 30 SW 15 - 25 SSW 20 - 35 --- - SSW 25 - 35
Wednesday Night SSE 10 - 20 SSE 10 - 20 SW 20 - 35 --- - SW 30 - 40
Thursday Morning SW 20 - 30 SW 10 - 20 SW 20 - 35 --- - SW 30 - 40
Thursday Afternoon SW 10 - 20 SW 5 - 15 SW 25 - 50 --- - WSW 60 - 70
Mt. Baker Direction - Speed
Wednesday SW 20 - 30
Wednesday Night SSE 10 - 20
Thursday Morning SW 20 - 30
Thursday Afternoon SW 10 - 20
Thursday Night SW 10 - 20
Washington Pass Direction - Speed
Wednesday SW 15 - 25
Wednesday Night SSE 10 - 20
Thursday Morning SW 10 - 20
Thursday Afternoon SW 5 - 15
Thursday Night WSW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Wednesday SSW 20 - 35
Wednesday Night SW 20 - 35
Thursday Morning SW 20 - 35
Thursday Afternoon SW 25 - 50
Thursday Night WSW 30 - 40
Mt. Rainier Direction - Speed
Wednesday --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday SSW 25 - 35
Wednesday Night SW 30 - 40
Thursday Morning SW 30 - 40
Thursday Afternoon WSW 60 - 70
Thursday Night SW 45 - 55

Extended Weather Synopsis for Saturday night through Saturday

Another front on the heels of the last system should move in Friday afternoon with light rain and snow developing over the area. This system will also not linger very long... with showers rapidly decreasing on Saturday and some partial clearing possible in the afternoon. This frontal system should also usher in a colder air mass. 

The respite from the active weather ends on Sunday as the next Pacific frontal system approaches from the west and spreads light rain and snow inland during the day. 

Extended Weather

Olympics, Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Friday

Cloudy with increasing light rain and snow in the afternoon. 

Friday Night

Light rain and snow showers, occasionally moderate west slopes and Mt. Hood. Showers decreasing late Friday night. Cooling trend. 

Saturday

Mostly cloudy with scattered light rain and snow showers in the morning becoming partly cloudy in the afternoon. 

Saturday Night

Partly to mostly clear. 

Sunday

Increasing clouds with light rain and snow developing in the afternoon. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Friday Snow Level 3000' - 4000' 3000' - 4000' 3500' - 4500'
Friday Night - Saturday Snow Level 2000' - 3000' 2000' - 3000' 2000' - 3000'
Saturday Night Snow Level 1000' - 2000' 1500' - 2500' 3000' - 4000'
Mt. Baker Elevation
Friday Snow Level
3000' - 4000'
Friday Night - Saturday Snow Level
2000' - 3000'
Saturday Night Snow Level
1000' - 2000'
Sunday Snow Level
3000' - 4000'
Snoqualmie Pass Elevation
Friday Snow Level
3000' - 4000'
Friday Night - Saturday Snow Level
2000' - 3000'
Saturday Night Snow Level
1500' - 2500'
Sunday Snow Level
3000' - 4000'
Mt. Hood Elevation
Friday Snow Level
3500' - 4500'
Friday Night - Saturday Snow Level
2000' - 3000'
Saturday Night Snow Level
3000' - 4000'
Sunday Snow Level
4000' - 5000'

* 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 12, 2016

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