Issued: 7:20 AM PST Wednesday, January 6, 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 & Thursday

A upper level low hanging around offshore continues to rotate upper level shortwaves through the area in southerly flow aloft. A band of light rain and snow over the Olympics and Vancouver Island should rotate north later this morning, with another band down along the central Oregon coast. 

A partial clearing trend should take place this afternoon as most of the area will be between shortwaves, with the clearing most pronounced west of the Cascade crest. Low level easterly flow should maintain cloud cover over the east slopes along with some light rain or snow. There should be a gradual warming trend this afternoon. 

The upper level low will slowly dig SE overnight and the PNW will be left in no-man's land regarding upper level flow and forcing as the jet stream is well south and directed into the Baja Peninsula. A few mountain showers could pop up in the afternoon with a weakly unstable air mass overhead. 

Weather Forecast

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

Mostly cloudy with a chance of light rain and snow, except a chance of light freezing rain near the Cascade Passes. 

Wednesday Afternoon - Thursday Morning

Partly to mostly clear, except mostly cloudy near the Cascade Passes. 

Olympics
Wednesday Morning

Cloudy with occasional light rain and snow. 

Wednesday Afternoon - Thursday Morning

Mostly clear. 

Mt. Hood Area
Wednesday

Mostly cloudy with a chance of light rain and snow, possible sunbreaks mid-day. 

Wednesday Night - Thursday Morning

Mostly cloudy. 

East slopes of the Washington Cascades
Wednesday

Mostly cloudy with a chance of light rain and snow, except a chance of light freezing rain near the Cascade Passes. 

Thursday Afternoon - Thursday Night

Partly to mostly cloudy with a chance of a light rain or snow shower Thursday afternoon. 

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 * 4000' 4000' 2500' ' ' 2500' ' 4000'
Wednesday Afternoon Snow Level * 5500' 5500' 4000' ' ' 3500' ' 5000'
Wednesday Night - Thursday Morning Snow Level * 4000' 3500' 2500' ' ' 2500' ' 3500'
Thursday Afternoon Snow Level * 3500' 3000' 3000' ' ' 3500' ' 3500'
Hurricane Ridge Elevation
Wednesday Morning Snow Level
4000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
5500'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
4000'
(Easterly Flow *)
Thursday Afternoon Snow Level
3500'
(Easterly Flow *)
Thursday Night Freezing Level
3500'
(Easterly Flow *)
Mt. Baker Elevation
Wednesday Morning Snow Level
4000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
5500'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
3500'
(Easterly Flow *)
Thursday Afternoon Snow Level
3000'
(Easterly Flow *)
Thursday Night Freezing Level
2500'
(Easterly Flow *)
Washington Pass Elevation
Wednesday Morning Snow Level
2500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
4000'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
2500'
(Easterly Flow *)
Thursday Afternoon Snow Level
3000'
(Easterly Flow *)
Thursday Night Freezing Level
2500'
(Easterly Flow *)
Leavenworth Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Freezing Level
'
(Easterly Flow *)
Stevens Pass Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Freezing Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Wednesday Morning Snow Level
2500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
3500'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
2500'
(Easterly Flow *)
Thursday Afternoon Snow Level
3500'
(Easterly Flow *)
Thursday Night Freezing Level
2500'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Freezing Level
'
(Easterly Flow *)
Mt. Hood Elevation
Wednesday Morning Snow Level
4000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
5000'
(Easterly Flow *)
Wednesday Night - Thursday Morning Snow Level
3500'
(Easterly Flow *)
Thursday Afternoon Snow Level
3500'
(Easterly Flow *)
Thursday Night Freezing Level
3500'
(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

Thursday Thursday
Hurricane Ridge LT 0.10 LT 0.10
Mt Baker Ski Area LT 0.10 LT 0.10
Washington Pass LT 0.10 LT 0.10
Stevens Pass LT 0.10 LT 0.10
Snoqualmie Pass LT 0.10 LT 0.10
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.10 LT 0.10
Paradise LT 0.10 LT 0.10
White Pass LT 0.10 LT 0.10
Mt Hood Meadows LT 0.10 LT 0.10
LT 0.10 LT 0.10

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Wednesday Morning - Wednesday Mid-day S 15 - 25 SE 5 - 15 ESE 5 - 15 --- - SE 5 - 15
Wednesday Afternoon SE 0 - 10 SE 0 - 10 SE 5 - 15 --- - SSE 10 - 20
Wednesday Night SE 0 - 10 VAR 0 - 10 VAR 0 - 10 --- - VAR 0 - 10
Hurricane Ridge Elevation
Wednesday Morning - Wednesday Mid-day S 15 - 25
Wednesday Afternoon SE 0 - 10
Wednesday Night SE 0 - 10
Thursday - Thursday Night VAR 0 - 10
Mt. Baker Elevation
Wednesday Morning - Wednesday Mid-day SE 5 - 15
Wednesday Afternoon SE 0 - 10
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NNE 0 - 10
Stevens and Snoqualmie Pass Elevation
Wednesday Morning - Wednesday Mid-day ESE 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NW 0 - 10
Mt. Rainier Elevation
Wednesday Morning - Wednesday Mid-day --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday - Thursday Night --- -
Mt. Hood Elevation
Wednesday Morning - Wednesday Mid-day SE 5 - 15
Wednesday Afternoon SSE 10 - 20
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NW 0 - 10
Hurricane Ridge Direction - Speed
Wednesday Morning - Wednesday Mid-day S 15 - 25
Wednesday Afternoon SE 0 - 10
Wednesday Night SE 0 - 10
Thursday - Thursday Night VAR 0 - 10
Mt. Baker Direction - Speed
Wednesday Morning - Wednesday Mid-day SE 5 - 15
Wednesday Afternoon SE 0 - 10
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NNE 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning - Wednesday Mid-day ESE 5 - 15
Wednesday Afternoon SE 5 - 15
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NW 0 - 10
Mt. Rainier Direction - Speed
Wednesday Morning - Wednesday Mid-day --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday - Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning - Wednesday Mid-day SE 5 - 15
Wednesday Afternoon SSE 10 - 20
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NW 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
Wednesday Morning - Wednesday Mid-day S 10 - 20 S 10 - 20 S 10 - 20 --- - S 10 - 20
Wednesday Afternoon SE 0 - 10 SE 0 - 10 SE 5 - 15 --- - SSE 10 - 20
Wednesday Night N 0 - 10 N 0 - 10 VAR 0 - 10 --- - NW 0 - 10
Mt. Baker Direction - Speed
Wednesday Morning - Wednesday Mid-day S 10 - 20
Wednesday Afternoon SE 0 - 10
Wednesday Night N 0 - 10
Thursday - Thursday Night NNW 0 - 10
Washington Pass Direction - Speed
Wednesday Morning - Wednesday Mid-day S 10 - 20
Wednesday Afternoon SE 0 - 10
Wednesday Night N 0 - 10
Thursday - Thursday Night NNW 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning - Wednesday Mid-day S 10 - 20
Wednesday Afternoon SE 5 - 15
Wednesday Night VAR 0 - 10
Thursday - Thursday Night NW 5 - 15
Mt. Rainier Direction - Speed
Wednesday Morning - Wednesday Mid-day --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday - Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning - Wednesday Mid-day S 10 - 20
Wednesday Afternoon SSE 10 - 20
Wednesday Night NW 0 - 10
Thursday - Thursday Night NW 0 - 10

Extended Weather Synopsis for Thursday night through Thursday

Friday should be a drier and mostly clear day. Colder air from the interior of Canada and interior West should slowly work it's way eastward as offshore pressure gradients increase. A weak weather system approaching from the west will begin to split and slide south toward the Oregon/California border late Friday night. 

Currently, the GFS model has light rain and snow spreading over the Mt. Hood area Saturday. Models disagree how far north this light precipitation may reach into the Washington Cascades Saturday and Saturday night. On Sunday, light NW flow aloft will keep mostly cloudy skies and the chance of showers in the forecast. 

Extended Weather

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

Mostly clear, except partly cloudy east slopes. Increasing clouds late Friday night Mt. Hood area. 

Saturday

Light rain and snow Mt. Hood area.  Becoming mostly cloudy south Washington Cascades and partly cloudy north Washington Cascades and Olympics. 

Saturday Night

Mostly cloudy with a chance of light rain and snow mainly south Washington Cascades and Mt. Hood. 

Sunday

Mostly cloudy with isolated rain and snow showers. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Friday - Friday Night Snow Level 2500' - 3500' 2500' - 3500' 2500' - 3500' *
Mt. Baker Elevation
Friday - Friday Night Snow Level
2500' - 3500'
(Easterly Flow *)
Saturday - Sunday Snow Level
2000' - 3000'
(Easterly Flow *)
Snoqualmie Pass Elevation
Friday - Friday Night Snow Level
2500' - 3500'
(Easterly Flow *)
Saturday - Sunday Snow Level
2500' - 3500'
(Easterly Flow *)
Mt. Hood Elevation
Friday - Friday Night Snow Level
2500' - 3500'
(Easterly Flow *)
Saturday - Sunday Snow Level
3000' - 4000'
(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.

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather

Previous forecast from Jan 1, 2016

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