Issued: 7:26 AM PST Sunday, December 25, 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 Sunday & Monday

A shortwave ridge moving over the PNW will provide us with some fine weather on Christmas Day. Freezing levels will be low but at least skies will be mostly clear with light winds.

The fair weather will not last long as a strong westerly jet once again becomes squarely aimed at Washington Monday night.  High clouds should increase overnight and through Monday morning as moisture begins to stream into the region.

Cloud ceilings should lower quickly Monday afternoon with light rain and snow spreading south from the Olympics and north Cascades. Alpine winds will also ramp up quickly Monday afternoon, so expect reduced visibility late in the day if above treeline. 

The bulk of precipitation from the incoming frontal system will move in Monday night.  A slight warming trend should take place overnight out ahead of and with the frontal passage for the Olympics and west slopes of the Cascades with snow levels peaking around 3000 feet after midnight through the early morning hours of Tuesday for the central Cascades including Snoqualmie Pass and 3500 feet for the south Washington Cascades including Crystal, Paradise and White Pass.

Heavy precipitation will hold off until after midnight for Mt. Hood as the front slowly sags south. 

 

Weather Forecast

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

Mostly sunny. 

Sunday Night - Monday Morning

Mostly clear becoming mostly cloudy late Sunday night with increasing high clouds. Light snow developing north Cascades Monday morning.  

Monday Afternoon

Clouds lowering with alpine winds increasing. Light snow. 

Olympics
Sunday

Mostly sunny. 

Sunday Night

Mostly clear becoming mostly cloudy overnight with increasing high clouds. 

Monday

Light rain and snow. Becoming windy in the afternoon. 

East slopes of the Washington Cascades
Sunday

Mostly sunny. 

Sunday Night - Monday Morning

Mostly clear becoming mostly cloudy late Sunday night with increasing high clouds. Very light snow developing northeast Cascades Monday morning.  

Monday Afternoon

Clouds lowering with alpine winds increasing. Light snow northeast Cascades spreading south in the afternoon. 

Mt. Hood Area
Sunday

Mostly sunny. 

Sunday Night - Monday Morning

Mostly clear becoming partly cloudy late Sunday night with increasing high clouds.

Monday Afternoon

Becoming mostly cloudy with alpine winds increasing.  

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Sunday - Sunday Night Freezing Level 1000' 500' 500' ' ' 500' ' 1000'
Monday Morning Snow Level * 2000' 500' 500' ' ' 1000' ' 1500'
Monday Afternoon - Monday Evening Snow Level * 3000' 1500' 500' ' ' 1500' ' 2000'
Hurricane Ridge Elevation
Sunday - Sunday Night Freezing Level
1000'
Monday Morning Snow Level
2000'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
3000'
(Easterly Flow *)
Monday Night Snow Level
4000'
(Easterly Flow *)
Mt. Baker Elevation
Sunday - Sunday Night Freezing Level
500'
Monday Morning Snow Level
500'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
1500'
(Easterly Flow *)
Monday Night Snow Level
2500'
(Easterly Flow *)
Washington Pass Elevation
Sunday - Sunday Night Freezing Level
500'
Monday Morning Snow Level
500'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
500'
(Easterly Flow *)
Monday Night Snow Level
2000'
(Easterly Flow *)
Leavenworth Elevation
Sunday - Sunday Night Freezing Level
'
Monday Morning Snow Level
'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Sunday - Sunday Night Freezing Level
'
Monday Morning Snow Level
'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Sunday - Sunday Night Freezing Level
500'
Monday Morning Snow Level
1000'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
1500'
(Easterly Flow *)
Monday Night Snow Level
3000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Sunday - Sunday Night Freezing Level
'
Monday Morning Snow Level
'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
'
(Easterly Flow *)
Monday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Sunday - Sunday Night Freezing Level
1000'
Monday Morning Snow Level
1500'
(Easterly Flow *)
Monday Afternoon - Monday Evening Snow Level
2000'
(Easterly Flow *)
Monday Night Snow Level
4500'
(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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Sunday VAR 0 - 10 VAR 0 - 10 VAR 0 - 10 --- - W 0 - 10
Sunday Night - Monday Morning SW 0 - 10 SW 0 - 10 SW 0 - 10 --- - SW 0 - 10
Monday Afternoon SW 20 - 30 S 15 - 25 S 15 - 25 --- - SW 10 - 20
Hurricane Ridge Elevation
Sunday VAR 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon SW 20 - 30
Monday Night SW 20 - 30
Mt. Baker Elevation
Sunday VAR 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon S 15 - 25
Monday Night SW 20 - 30
Stevens and Snoqualmie Pass Elevation
Sunday VAR 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon S 15 - 25
Monday Night WSW 20 - 35
Mt. Rainier Elevation
Sunday --- -
Sunday Night - Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Mt. Hood Elevation
Sunday W 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon SW 10 - 20
Monday Night WSW 35 - 45
Hurricane Ridge Direction - Speed
Sunday VAR 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon SW 20 - 30
Monday Night SW 20 - 30
Mt. Baker Direction - Speed
Sunday VAR 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon S 15 - 25
Monday Night SW 20 - 30
Stevens and Snoqualmie Pass Direction - Speed
Sunday VAR 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon S 15 - 25
Monday Night WSW 20 - 35
Mt. Rainier Direction - Speed
Sunday --- -
Sunday Night - Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Mt. Hood Direction - Speed
Sunday W 0 - 10
Sunday Night - Monday Morning SW 0 - 10
Monday Afternoon SW 10 - 20
Monday Night WSW 35 - 45

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
Sunday NW 0 - 10 NW 0 - 10 NW 0 - 10 --- - NW 0 - 10
Sunday Night - Monday Morning WNW 10 - 20 WNW 10 - 20 WNW 10 - 20 --- - WNW 10 - 20
Monday Afternoon SW 30 - 40 SW 30 - 40 SW 30 - 40 --- - WSW 25 - 35
Mt. Baker Direction - Speed
Sunday NW 0 - 10
Sunday Night - Monday Morning WNW 10 - 20
Monday Afternoon SW 30 - 40
Monday Night SW 35 - 50
Washington Pass Direction - Speed
Sunday NW 0 - 10
Sunday Night - Monday Morning WNW 10 - 20
Monday Afternoon SW 30 - 40
Monday Night SW 40 - 50
Stevens and Snoqualmie Pass Direction - Speed
Sunday NW 0 - 10
Sunday Night - Monday Morning WNW 10 - 20
Monday Afternoon SW 30 - 40
Monday Night WSW 50 - 60
Mt. Rainier Direction - Speed
Sunday --- -
Sunday Night - Monday Morning --- -
Monday Afternoon --- -
Monday Night --- -
Mt. Hood Direction - Speed
Sunday NW 0 - 10
Sunday Night - Monday Morning WNW 10 - 20
Monday Afternoon WSW 25 - 35
Monday Night WSW 60 - 70

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 24, 2016

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