Issued: 7:12 AM PST Friday, December 16, 2016
by Dennis D'Amico

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

Weather Synopsis for Friday & Wednesday

A longwave upper trough is digging off the California coast while dry northerly flow is seen aloft and at the surface over the PNW. The sensible weather effects can best be summarized as it's cold out there and the winds are relatively light. The cold weather station winner this morning on the NWAC network looks to be the Washington Pass base station (elev 5450 ft) checking in with -8F at 6 am. Low/mid clouds along the east slopes with ceilings in the 2500-4500 ft range are getting pulled through the Cascade Passes with weak easterly flow with only scattered mid level clouds elsewhere. By Friday afternoon generally sunny skies should be seen everywhere. 

A weak upper level shortwave approaching in NW flow aloft will pass through the Washington Cascades Saturday. This will increase high clouds Friday night and moisture up to about crest level on Saturday. Expect mostly cloudy conditions along the west slopes with a few sunbreak holes mostly likely to poke out for the Mt. Baker area and the Olympics and decreasing cloud cover further east of the Cascade crest. A few light snow showers are likely on Saturday along the west slopes as well.

Warm frontal moisture also coming down in NW flow aloft will begin to nick the Olympics and north Cascades with light precipitation early Sunday morning. Temperatures will remain cold through the short term with snow/freezing levels near sea level. 

 

Weather Forecast

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

Partly cloudy except mostly cloudy Cascade Passes. Cold. 

Friday Afternoon

Mostly sunny and cold. 

Friday Night

Mostly clear, then becoming mostly cloudy overnight with increasing mid and high clouds. 

East slopes of the Washington Cascades
Friday Morning

Cloudy. Cold. 

Friday Afternoon

Becoming partly to mostly sunny. Cold. 

Friday Night

Mostly clear, then becoming partly to mostly cloudy overnight with increasing mid and high clouds. 

Olympics
Friday Morning

Mostly clear except partly to mostly cloudy north slopes of the Olympics. Light to moderate NE winds. 

Friday Afternoon

Mostly sunny and cold. 

Friday Night

Mostly clear, then becoming mostly cloudy overnight with increasing mid and high clouds. 

Saturday

Mostly cloudy with occasional light snow showers mainly in the morning, becoming partly sunny Saturday afternoon. 

Mt. Hood Area
Friday Morning

Partly cloudy. Cold. 

Friday Afternoon

Mostly sunny and cold. 

Friday Night

Mostly clear, then becoming mostly cloudy overnight with increasing mid and high clouds. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Friday - Friday Night Freezing Level 0' 0' 0' ' ' 0' ' 0'
Hurricane Ridge Elevation
Friday - Friday Night Freezing Level
0'
Saturday - Saturday Night Snow Level
500'
Mt. Baker Elevation
Friday - Friday Night Freezing Level
0'
Saturday - Saturday Night Snow Level
0'
Washington Pass Elevation
Friday - Friday Night Freezing Level
0'
Saturday - Saturday Night Snow Level
0'
Leavenworth Elevation
Friday - Friday Night Freezing Level
'
Saturday - Saturday Night Snow Level
'
Stevens Pass Elevation
Friday - Friday Night Freezing Level
'
Saturday - Saturday Night Snow Level
'
Snoqualmie Pass Elevation
Friday - Friday Night Freezing Level
0'
Saturday - Saturday Night Snow Level
0'
Mt. Rainier & Crystal Elevation
Friday - Friday Night Freezing Level
'
Saturday - Saturday Night Snow Level
'
Mt. Hood Elevation
Friday - Friday Night Freezing Level
0'
Saturday - Saturday Night Snow Level
500'

* 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

Wednesday Wednesday
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
Friday Morning NE 10 - 20 NE 5 - 15 E 0 - 10 --- - E 0 - 10
Friday Afternoon N 0 - 10 NE 0 - 10 VAR 0 - 10 --- - VAR 0 - 10
Friday Night - Saturday Morning W 5 - 15 W 0 - 10 W 0 - 10 --- - W 5 - 15
Hurricane Ridge Elevation
Friday Morning NE 10 - 20
Friday Afternoon N 0 - 10
Friday Night - Saturday Morning W 5 - 15
Saturday Afternoon - Saturday Night NW 10 - 20
Mt. Baker Elevation
Friday Morning NE 5 - 15
Friday Afternoon NE 0 - 10
Friday Night - Saturday Morning W 0 - 10
Saturday Afternoon - Saturday Night VAR 0 - 10
Stevens and Snoqualmie Pass Elevation
Friday Morning E 0 - 10
Friday Afternoon VAR 0 - 10
Friday Night - Saturday Morning W 0 - 10
Saturday Afternoon - Saturday Night WNW 5 - 15
Mt. Rainier Elevation
Friday Morning --- -
Friday Afternoon --- -
Friday Night - Saturday Morning --- -
Saturday Afternoon - Saturday Night --- -
Mt. Hood Elevation
Friday Morning E 0 - 10
Friday Afternoon VAR 0 - 10
Friday Night - Saturday Morning W 5 - 15
Saturday Afternoon - Saturday Night WNW 10 - 20
Hurricane Ridge Direction - Speed
Friday Morning NE 10 - 20
Friday Afternoon N 0 - 10
Friday Night - Saturday Morning W 5 - 15
Saturday Afternoon - Saturday Night NW 10 - 20
Mt. Baker Direction - Speed
Friday Morning NE 5 - 15
Friday Afternoon NE 0 - 10
Friday Night - Saturday Morning W 0 - 10
Saturday Afternoon - Saturday Night VAR 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning E 0 - 10
Friday Afternoon VAR 0 - 10
Friday Night - Saturday Morning W 0 - 10
Saturday Afternoon - Saturday Night WNW 5 - 15
Mt. Rainier Direction - Speed
Friday Morning --- -
Friday Afternoon --- -
Friday Night - Saturday Morning --- -
Saturday Afternoon - Saturday Night --- -
Mt. Hood Direction - Speed
Friday Morning E 0 - 10
Friday Afternoon VAR 0 - 10
Friday Night - Saturday Morning W 5 - 15
Saturday Afternoon - Saturday Night WNW 10 - 20

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
Friday Morning NNE 10 - 20 N 15 - 25 NNE 5 - 15 --- - N 5 - 15
Friday Afternoon N 10 - 20 N 15 - 30 N 15 - 25 --- - N 15 - 25
Friday Night NW 15 - 25 NW 10 - 20 NW 15 - 30 --- - NW 15 - 30
Mt. Baker Direction - Speed
Friday Morning NNE 10 - 20
Friday Afternoon N 10 - 20
Friday Night NW 15 - 25
Saturday - Saturday Night NW 15 - 25
Washington Pass Direction - Speed
Friday Morning N 15 - 25
Friday Afternoon N 15 - 30
Friday Night NW 10 - 20
Saturday - Saturday Night NNW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning NNE 5 - 15
Friday Afternoon N 15 - 25
Friday Night NW 15 - 30
Saturday - Saturday Night NW 20 - 35
Mt. Rainier Direction - Speed
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday - Saturday Night --- -
Mt. Hood Direction - Speed
Friday Morning N 5 - 15
Friday Afternoon N 15 - 25
Friday Night NW 15 - 30
Saturday - Saturday Night NW 20 - 30

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.

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

Previous forecast from Dec 15, 2016

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