Issued: 7:06 AM PST Thursday, December 3, 2020
by Robert Hahn

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

Weather Synopsis for Thursday & Thursday

A persistent high-amplitude ridge continues to shield the Pacific Northwest from storm activity this week. An approaching shortwave trough falls apart as it approaches the coastline on Thursday, running into the ridge. The approaching weak trough shifts upper-level winds to the SW on Thursday and W on Thursday night. The mid-level clouds offshore should move onshore bringing mostly cloudy to the region after a mostly sunny start to the day. They could also bring a sprinkle to the Olympics in the afternoon or in the evening hours for the west slopes of the Cascades.

The situation near the surface continues to be more complicated with a cold air pool remaining, but slowly thinning E of the Cascade Crest (below 5000 ft) and a pressure gradient driving moderate E gap winds that has been slower to decrease than expected Wednesday night. Alpental Summit saw sustained strong ESE winds overnight, which have recently come down into the moderate range. SW flow combined with the ridge axis drifting farther east, should help the milder air to the west to invade the dense cold pool east of the Cascade Crest, which should taper these winds over the course of the day.

Thursday night, expect mild conditions in many locations with a much shallower inversion developing in valleys E and W of the Cascade Crest. The ridge rebounds over the region on Friday, dissipating the clouds to bring another sunny day. Easterly gap flow should also increase throughout the day, with E winds in the moderate range by mid-day through the mountain gaps. Strong winds are once again possible by late in the day as the cold air pool banks back up against the E slopes of the Cascades.

Weather Forecast

Hurricane Ridge
Mt. Baker
Washington Pass and Leavenworth
Stevens and Snoqualmie Pass
Mt. Rainier, Crystal and White Pass
Mt. Hood

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Thursday Morning Freezing Level * 10500' 7500' 2000' 1500' 2000' 2500' 3500' 3500'
Thursday Afternoon Freezing Level * 9500' 10000' 10500' 11000' 10500' 10500' 10500' 10500'
Thursday Evening Freezing Level * 9000' 8000' 8500' 8500' 8000' 8500' 8500' 9000'
Thursday Night Freezing Level 10000' 10000' 9000' 8500' 9000' 9000' 9000' 9000'
Friday Morning Freezing Level * 10000' 10500' 10500' 10000' 10000' 10000' 10000' 10000'
Hurricane Ridge Elevation
Thursday Morning Freezing Level
10500'
(Easterly Flow *)
Thursday Afternoon Freezing Level
9500'
(Easterly Flow *)
Thursday Evening Freezing Level
9000'
(Easterly Flow *)
Thursday Night Freezing Level
10000'
Friday Morning Freezing Level
10000'
(Easterly Flow *)
Friday Afternoon Freezing Level
10500'
(Easterly Flow *)
Mt. Baker Elevation
Thursday Morning Freezing Level
7500'
(Easterly Flow *)
Thursday Afternoon Freezing Level
10000'
(Easterly Flow *)
Thursday Evening Freezing Level
8000'
(Easterly Flow *)
Thursday Night Freezing Level
10000'
Friday Morning Freezing Level
10500'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(Easterly Flow *)
Washington Pass Elevation
Thursday Morning Freezing Level
2000'
(Easterly Flow *)
Thursday Afternoon Freezing Level
10500'
(Easterly Flow *)
Thursday Evening Freezing Level
8500'
(Easterly Flow *)
Thursday Night Freezing Level
9000'
Friday Morning Freezing Level
10500'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(Easterly Flow *)
Leavenworth Elevation
Thursday Morning Freezing Level
1500'
(Easterly Flow *)
Thursday Afternoon Freezing Level
11000'
(Easterly Flow *)
Thursday Evening Freezing Level
8500'
(Easterly Flow *)
Thursday Night Freezing Level
8500'
Friday Morning Freezing Level
10000'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(Easterly Flow *)
Stevens Pass Elevation
Thursday Morning Freezing Level
2000'
(Easterly Flow *)
Thursday Afternoon Freezing Level
10500'
(Easterly Flow *)
Thursday Evening Freezing Level
8000'
(Easterly Flow *)
Thursday Night Freezing Level
9000'
Friday Morning Freezing Level
10000'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(Easterly Flow *)
Snoqualmie Pass Elevation
Thursday Morning Freezing Level
2500'
(Easterly Flow *)
Thursday Afternoon Freezing Level
10500'
(Easterly Flow *)
Thursday Evening Freezing Level
8500'
(Easterly Flow *)
Thursday Night Freezing Level
9000'
Friday Morning Freezing Level
10000'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Thursday Morning Freezing Level
3500'
(Easterly Flow *)
Thursday Afternoon Freezing Level
10500'
(Easterly Flow *)
Thursday Evening Freezing Level
8500'
(Easterly Flow *)
Thursday Night Freezing Level
9000'
Friday Morning Freezing Level
10000'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(Easterly Flow *)
Mt. Hood Elevation
Thursday Morning Freezing Level
3500'
(Easterly Flow *)
Thursday Afternoon Freezing Level
10500'
(Easterly Flow *)
Thursday Evening Freezing Level
9000'
(Easterly Flow *)
Thursday Night Freezing Level
9000'
Friday Morning Freezing Level
10000'
(Easterly Flow *)
Friday Afternoon Freezing Level
11000'
(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 Night Thursday
4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 0 0
Mt Baker Ski Area 0 0 0
Washington Pass 0 0 0
Leavenworth 0 0 0
Stevens Pass 0 0 0
Snoqualmie Pass 0 0 0
Mission Ridge 0 0 0
Crystal Mt 0 0 0
Paradise 0 0 0
White Pass 0 0 0
Mt Hood Meadows 0 0 0
0 0 0
Hurricane Ridge Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Mt Baker Ski Area Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Washington Pass Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Leavenworth Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Stevens Pass Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Snoqualmie Pass Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Mission Ridge Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Crystal Mt Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Paradise Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
White Pass Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Mt Hood Meadows Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0
Timberline Precipitation Forecast
Thursday 0
Thursday Night 0
Thursday 0

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Thursday Morning SW 5 - 15 SSW 10 - 20 ESE 15 - 25 SW 0 - 10 WSW 0 - 10
Thursday Afternoon SW 5 - 15 SW 10 - 20 ESE 5 - 15 W 0 - 10 W 5 - 15
Thursday Evening SW 0 - 10 SSW 5 - 15 W 0 - 10 W 0 - 10 WNW 5 - 15
Thursday Night SW 0 - 10 WSW 0 - 10 W 0 - 10 W 0 - 10 W 0 - 10
Friday Morning SW 0 - 10 WNW 0 - 10 ESE 10 - 20 NNW 0 - 10 ESE 5 - 15
Hurricane Ridge Elevation
Thursday Morning SW 5 - 15
Thursday Afternoon SW 5 - 15
Thursday Evening SW 0 - 10
Thursday Night SW 0 - 10
Friday Morning SW 0 - 10
Friday Afternoon SSE 0 - 15
Mt. Baker Elevation
Thursday Morning SSW 10 - 20
Thursday Afternoon SW 10 - 20
Thursday Evening SSW 5 - 15
Thursday Night WSW 0 - 10
Friday Morning WNW 0 - 10
Friday Afternoon W 0 - 10
Stevens and Snoqualmie Pass Elevation
Thursday Morning ESE 15 - 25
Thursday Afternoon ESE 5 - 15
Thursday Evening W 0 - 10
Thursday Night W 0 - 10
Friday Morning ESE 10 - 20
Friday Afternoon ESE 15 - 25
Mt. Rainier Elevation
Thursday Morning SW 0 - 10
Thursday Afternoon W 0 - 10
Thursday Evening W 0 - 10
Thursday Night W 0 - 10
Friday Morning NNW 0 - 10
Friday Afternoon ESE 5 - 15
Mt. Hood Elevation
Thursday Morning WSW 0 - 10
Thursday Afternoon W 5 - 15
Thursday Evening WNW 5 - 15
Thursday Night W 0 - 10
Friday Morning ESE 5 - 15
Friday Afternoon ESE 10 - 20
Hurricane Ridge Direction - Speed
Thursday Morning SW 5 - 15
Thursday Afternoon SW 5 - 15
Thursday Evening SW 0 - 10
Thursday Night SW 0 - 10
Friday Morning SW 0 - 10
Friday Afternoon SSE 0 - 15
Mt. Baker Direction - Speed
Thursday Morning SSW 10 - 20
Thursday Afternoon SW 10 - 20
Thursday Evening SSW 5 - 15
Thursday Night WSW 0 - 10
Friday Morning WNW 0 - 10
Friday Afternoon W 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Thursday Morning ESE 15 - 25
Thursday Afternoon ESE 5 - 15
Thursday Evening W 0 - 10
Thursday Night W 0 - 10
Friday Morning ESE 10 - 20
Friday Afternoon ESE 15 - 25
Mt. Rainier Direction - Speed
Thursday Morning SW 0 - 10
Thursday Afternoon W 0 - 10
Thursday Evening W 0 - 10
Thursday Night W 0 - 10
Friday Morning NNW 0 - 10
Friday Afternoon ESE 5 - 15
Mt. Hood Direction - Speed
Thursday Morning WSW 0 - 10
Thursday Afternoon W 5 - 15
Thursday Evening WNW 5 - 15
Thursday Night W 0 - 10
Friday Morning ESE 5 - 15
Friday Afternoon ESE 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
Thursday Morning SSW 15 - 25 SW 10 - 20 WSW 10 - 20 WSW 10 - 20 WSW 10 - 20
Thursday Afternoon WSW 15 - 25 WSW 15 - 25 W 15 - 25 W 10 - 20 WSW 15 - 25
Thursday Evening W 15 - 25 W 10 - 20 WNW 15 - 25 NW 10 - 20 WNW 10 - 20
Thursday Night WNW 15 - 25 WNW 10 - 20 NW 10 - 20 NNW 10 - 20 NNW 10 - 20
Friday Morning WNW 15 - 25 WNW 10 - 20 NW 10 - 20 N 5 - 15 NE 5 - 15
Mt. Baker Direction - Speed
Thursday Morning SSW 15 - 25
Thursday Afternoon WSW 15 - 25
Thursday Evening W 15 - 25
Thursday Night WNW 15 - 25
Friday Morning WNW 15 - 25
Friday Afternoon W 10 - 20
Washington Pass Direction - Speed
Thursday Morning SW 10 - 20
Thursday Afternoon WSW 15 - 25
Thursday Evening W 10 - 20
Thursday Night WNW 10 - 20
Friday Morning WNW 10 - 20
Friday Afternoon WSW 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Thursday Morning WSW 10 - 20
Thursday Afternoon W 15 - 25
Thursday Evening WNW 15 - 25
Thursday Night NW 10 - 20
Friday Morning NW 10 - 20
Friday Afternoon WNW 0 - 10
Mt. Rainier Direction - Speed
Thursday Morning WSW 10 - 20
Thursday Afternoon W 10 - 20
Thursday Evening NW 10 - 20
Thursday Night NNW 10 - 20
Friday Morning N 5 - 15
Friday Afternoon ESE 0 - 10
Mt. Hood Direction - Speed
Thursday Morning WSW 10 - 20
Thursday Afternoon WSW 15 - 25
Thursday Evening WNW 10 - 20
Thursday Night NNW 10 - 20
Friday Morning NE 5 - 15
Friday Afternoon ENE 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.

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

Previous forecast from Dec 2, 2020

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