Issued: 2:38 PM PST Sunday, December 8, 2019
by Robert Hahn

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

Weather Synopsis for Sunday night through Friday

An amplified ridge of high-pressure shifts eastward over the region Sunday night through Monday night. The arriving ridge brings a warming and drying trend, such that lingering low-level moisture should gradually dissipate, leaving most mountain regions mostly clear by Monday morning. Snoqualmie Pass is a potential exception where the low cloud may spill through the relatively low gap in the terrain through Monday morning.

The warming trend will be pronounced on Monday with freezing levels skyrocketing for one day and staying elevated through Monday night. Locations east of the Cascade Crest are likely to cool somewhat on Monday night as a light E flow develops.

On Tuesday, a dissipating frontal system reaches the coastline late in the day, spreading sone light rain and snow to the west slopes of the Olympics.

Weather Forecast

Hurricane Ridge
Sunday Night Low clouds gradually dissipating, leading to clearing skies.
Mt. Baker
Sunday Night Low clouds early, then becoming mostly clear with areas of valley fog.
Washington Pass and Leavenworth
Sunday Night Mostly clear.
Stevens and Snoqualmie Pass
Sunday Night Low clouds decreasing overnight, with clear skies above the cloud deck. Light W wind early becoming light and variable.
Mt. Rainier, Crystal and White Pass
Sunday Night Low clouds decreasing overnight, with clear skies above the cloud deck.
Mt. Hood
Sunday Night Mostly clear.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Sunday Evening Freezing Level 4500' 4000' 3500' 3500' 4000' 4500' 4500' 4500'
Sunday Night Freezing Level 5500' 3500' 3000' 3000' 3000' 3000' 3500' 4500'
Monday Morning Freezing Level 8500' 4500' 4000' 6000' 6000' 7000' 7500' 8000'
Monday Afternoon Freezing Level 9500' 6000' 5000' 6000' 6000' 7500' 8000' 9500'
Monday Evening Freezing Level * 8500' 5500' 4500' 4000' 4000' 6000' 6500' 9000'
Monday Night Freezing Level * 7500' 5500' 4500' 4000' 4000' 6000' 6500' 9000'
Tuesday Morning Freezing Level 5500' 5000' 4500' 5500' 5500' 5000' 5500' 7500'
Hurricane Ridge Elevation
Sunday Evening Freezing Level
4500'
Sunday Night Freezing Level
5500'
Monday Morning Freezing Level
8500'
Monday Afternoon Freezing Level
9500'
Monday Evening Freezing Level
8500'
(Easterly Flow *)
Monday Night Freezing Level
7500'
(Easterly Flow *)
Tuesday Morning Freezing Level
5500'
Tuesday Afternoon Freezing Level
5500'
Mt. Baker Elevation
Sunday Evening Freezing Level
4000'
Sunday Night Freezing Level
3500'
Monday Morning Freezing Level
4500'
Monday Afternoon Freezing Level
6000'
Monday Evening Freezing Level
5500'
(Easterly Flow *)
Monday Night Freezing Level
5500'
(Easterly Flow *)
Tuesday Morning Freezing Level
5000'
Tuesday Afternoon Freezing Level
5000'
Washington Pass Elevation
Sunday Evening Freezing Level
3500'
Sunday Night Freezing Level
3000'
Monday Morning Freezing Level
4000'
Monday Afternoon Freezing Level
5000'
Monday Evening Freezing Level
4500'
(Easterly Flow *)
Monday Night Freezing Level
4500'
(Easterly Flow *)
Tuesday Morning Freezing Level
4500'
Tuesday Afternoon Freezing Level
5000'
Leavenworth Elevation
Sunday Evening Freezing Level
3500'
Sunday Night Freezing Level
3000'
Monday Morning Freezing Level
6000'
Monday Afternoon Freezing Level
6000'
Monday Evening Freezing Level
4000'
(Easterly Flow *)
Monday Night Freezing Level
4000'
(Easterly Flow *)
Tuesday Morning Freezing Level
5500'
Tuesday Afternoon Freezing Level
5000'
Stevens Pass Elevation
Sunday Evening Freezing Level
4000'
Sunday Night Freezing Level
3000'
Monday Morning Freezing Level
6000'
Monday Afternoon Freezing Level
6000'
Monday Evening Freezing Level
4000'
(Easterly Flow *)
Monday Night Freezing Level
4000'
(Easterly Flow *)
Tuesday Morning Freezing Level
5500'
Tuesday Afternoon Freezing Level
5000'
Snoqualmie Pass Elevation
Sunday Evening Freezing Level
4500'
Sunday Night Freezing Level
3000'
Monday Morning Freezing Level
7000'
Monday Afternoon Freezing Level
7500'
Monday Evening Freezing Level
6000'
(Easterly Flow *)
Monday Night Freezing Level
6000'
(Easterly Flow *)
Tuesday Morning Freezing Level
5000'
Tuesday Afternoon Freezing Level
5000'
Mt. Rainier & Crystal Elevation
Sunday Evening Freezing Level
4500'
Sunday Night Freezing Level
3500'
Monday Morning Freezing Level
7500'
Monday Afternoon Freezing Level
8000'
Monday Evening Freezing Level
6500'
(Easterly Flow *)
Monday Night Freezing Level
6500'
(Easterly Flow *)
Tuesday Morning Freezing Level
5500'
Tuesday Afternoon Freezing Level
5500'
Mt. Hood Elevation
Sunday Evening Freezing Level
4500'
Sunday Night Freezing Level
4500'
Monday Morning Freezing Level
8000'
Monday Afternoon Freezing Level
9500'
Monday Evening Freezing Level
9000'
(Easterly Flow *)
Monday Night Freezing Level
9000'
(Easterly Flow *)
Tuesday Morning Freezing Level
7500'
Tuesday Afternoon Freezing Level
7000'

* 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

Sunday Night Friday Friday Night Friday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 0 0 0
Mt Baker Ski Area 0 0 0 0
Washington Pass 0 0 0 0
Leavenworth 0 0 0 0
Stevens Pass 0 0 0 0
Snoqualmie Pass 0 0 0 0
Mission Ridge 0 0 0 0
Crystal Mt 0 0 0 0
Paradise 0 0 0 0
White Pass 0 0 0 0
Mt Hood Meadows 0 0 0 0
0 0 0 0
Hurricane Ridge Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Mt Baker Ski Area Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Washington Pass Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Leavenworth Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Stevens Pass Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Snoqualmie Pass Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Mission Ridge Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Crystal Mt Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Paradise Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
White Pass Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Mt Hood Meadows Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0
Timberline Precipitation Forecast
Sunday Night 0
Friday 0
Friday Night 0
Friday 0

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Sunday Evening SSW 0 - 10 SW 0 - 10 W 0 - 10 WNW 0 - 10 W 5 - 15
Sunday Night W 0 - 10 WSW 0 - 10 W 0 - 10 SW 0 - 10 WNW 0 - 10
Monday Morning SSE 0 - 10 SW 0 - 10 WSW 0 - 10 WSW 0 - 10 WSW 0 - 10
Hurricane Ridge Elevation
Sunday Evening SSW 0 - 10
Sunday Night W 0 - 10
Monday Morning SSE 0 - 10
Monday Afternoon SSW 5 - 15
Mt. Baker Elevation
Sunday Evening SW 0 - 10
Sunday Night WSW 0 - 10
Monday Morning SW 0 - 10
Monday Afternoon SSW 0 - 10
Stevens and Snoqualmie Pass Elevation
Sunday Evening W 0 - 10
Sunday Night W 0 - 10
Monday Morning WSW 0 - 10
Monday Afternoon WSW 0 - 10
Mt. Rainier Elevation
Sunday Evening WNW 0 - 10
Sunday Night SW 0 - 10
Monday Morning WSW 0 - 10
Monday Afternoon WSW 0 - 10
Mt. Hood Elevation
Sunday Evening W 5 - 15
Sunday Night WNW 0 - 10
Monday Morning WSW 0 - 10
Monday Afternoon WSW 5 - 15
Hurricane Ridge Direction - Speed
Sunday Evening SSW 0 - 10
Sunday Night W 0 - 10
Monday Morning SSE 0 - 10
Monday Afternoon SSW 5 - 15
Mt. Baker Direction - Speed
Sunday Evening SW 0 - 10
Sunday Night WSW 0 - 10
Monday Morning SW 0 - 10
Monday Afternoon SSW 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Sunday Evening W 0 - 10
Sunday Night W 0 - 10
Monday Morning WSW 0 - 10
Monday Afternoon WSW 0 - 10
Mt. Rainier Direction - Speed
Sunday Evening WNW 0 - 10
Sunday Night SW 0 - 10
Monday Morning WSW 0 - 10
Monday Afternoon WSW 0 - 10
Mt. Hood Direction - Speed
Sunday Evening W 5 - 15
Sunday Night WNW 0 - 10
Monday Morning WSW 0 - 10
Monday Afternoon WSW 5 - 15

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 Evening N 10 - 20 N 20 - 30 N 10 - 20 NNE 10 - 20 NNW 10 - 20
Sunday Night NNW 5 - 15 N 15 - 25 N 5 - 15 NNE 5 - 15 NNW 10 - 20
Monday Morning NW 10 - 20 WNW 10 - 20 WNW 10 - 20 WNW 5 - 15 N 0 - 10
Mt. Baker Direction - Speed
Sunday Evening N 10 - 20
Sunday Night NNW 5 - 15
Monday Morning NW 10 - 20
Monday Afternoon WNW 10 - 20
Washington Pass Direction - Speed
Sunday Evening N 20 - 30
Sunday Night N 15 - 25
Monday Morning WNW 10 - 20
Monday Afternoon WNW 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Sunday Evening N 10 - 20
Sunday Night N 5 - 15
Monday Morning WNW 10 - 20
Monday Afternoon WNW 15 - 25
Mt. Rainier Direction - Speed
Sunday Evening NNE 10 - 20
Sunday Night NNE 5 - 15
Monday Morning WNW 5 - 15
Monday Afternoon WNW 10 - 20
Mt. Hood Direction - Speed
Sunday Evening NNW 10 - 20
Sunday Night NNW 10 - 20
Monday Morning N 0 - 10
Monday Afternoon W 10 - 20

Extended Weather Synopsis for Friday night through Friday

Tuesday night, the weak front moves inland and brings light rain and snow throughout the region. Expect mainly rain at Snoqualmie Pass, a mix of rain and snow at Stevens Pass, and all snow at Washington Pass and higher elevations west of the Cascade crest should pick up several inches of snow. Models disagree regarding whether or not Mt Hood will get precipitation.

A very weak ridge lies over the region on Wednesday, with weak post-frontal showers ending early and higher clouds lowering and thickening in the afternoon as the next storm approaches the coastline.

A stronger storm brings moderate precipitation on a WSW flow, Wednesday night and Thursday. Snow levels will be significantly lower in the north than the south of our region.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Tuesday Night Snow Level 3000' - 4000' 3500' - 4500' 6000' - 7000'
Wednesday Snow Level 3000' - 4000' 4000' - 6000' 6000' - 7000'
Wednesday Night Snow Level 3500' - 4500' 4500' - 5500' 6000' - 7000'
Mt. Baker Elevation
Tuesday Night Snow Level
3000' - 4000'
Wednesday Snow Level
3000' - 4000'
Wednesday Night Snow Level
3500' - 4500'
Thursday Snow Level
3000' - 4000'
Snoqualmie Pass Elevation
Tuesday Night Snow Level
3500' - 4500'
Wednesday Snow Level
4000' - 6000'
Wednesday Night Snow Level
4500' - 5500'
Thursday Snow Level
4000' - 5000'
Mt. Hood Elevation
Tuesday Night Snow Level
6000' - 7000'
Wednesday Snow Level
6000' - 7000'
Wednesday Night Snow Level
6000' - 7000'
Thursday Snow Level
5000' - 6000'

* 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 Dec 7, 2019

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