Issued: 1:45 PM PST Saturday, November 28, 2020
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 Saturday night through Sunday

Sunshine has taken hold over most areas this afternoon except for the central Cascades and the Stevens/Snoqualmie Passes area where leftover low level clouds are still in the process of clearing out. With an upper level ridge building over the area tonight and offshore (easterly) flow increasing, expect the overall drying trend to continue. 

A Pacific frontal system will approach the coast on Sunday, spreading some high and mid clouds over the Olympic Peninsula by mid-day, but meaningful cloud cover should hold off until the late afternoon for the Cascades. Freezing levels will be on the rise ahead of the front, peaking in the 6000-8000' range for all areas except the northeast and central-east Cascades where relatively cooler air will stay in place. With cool easterly flow, except temperature inversions, most pronounced in the major Cascade Passes, with the mildest temperatures generally found above 5000'. 

Precipitation should begin for the Cascades after midnight with the frontal passage occurring sometime during the early morning hours on Monday. Snow levels will drop quickly with the onset of precipitation and behind the front. There is still some forecast model divergence about how potent this system will be with the European and Canadian models suggesting the front will split and weaken more before arriving. Looking at wetter solutions, there's the potential for up to an inch of water (10+ inches of snow) along the west slopes of the Cascades through Monday along with strong post-frontal westerly winds. 

Weather Forecast

Hurricane Ridge
Saturday Night Mostly clear.
Mt. Baker
Saturday Night Mostly clear.
Washington Pass and Leavenworth
Saturday Night Mostly clear.
Stevens and Snoqualmie Pass
Saturday Night Mostly clear. Light east wind in the Passes becoming moderate overnight.
Mt. Rainier, Crystal and White Pass
Saturday Night Mostly clear.
Mt. Hood
Saturday 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
Saturday Evening Freezing Level 5500' 3500' 2500' 2500' 3000' 3500' 7500' 6500'
Saturday Night Freezing Level * 7000' 6000' 2500' 2500' 3500' 5500' 7500' 8500'
Sunday Morning Freezing Level * 7500' 6500' 3000' 3500' 5500' 7500' 7500' 8500'
Sunday Afternoon Freezing Level * 6500' 5500' 3500' 4000' 5500' 6500' 7000' 8000'
Sunday Evening Snow Level 5500' 4500' 3000' 3000' 5000' 5500' 6500' 7000'
Sunday Night Snow Level 4500' 3000' 2500' 2500' 3000' 3000' 4000' 5000'
Monday Morning Snow Level 3000' 3000' 2500' 2500' 3000' 3000' 3500' 3500'
Hurricane Ridge Elevation
Saturday Evening Freezing Level
5500'
Saturday Night Freezing Level
7000'
(Easterly Flow *)
Sunday Morning Freezing Level
7500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
6500'
(Easterly Flow *)
Sunday Evening Snow Level
5500'
Sunday Night Snow Level
4500'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2000'
Mt. Baker Elevation
Saturday Evening Freezing Level
3500'
Saturday Night Freezing Level
6000'
(Easterly Flow *)
Sunday Morning Freezing Level
6500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
5500'
(Easterly Flow *)
Sunday Evening Snow Level
4500'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2000'
Washington Pass Elevation
Saturday Evening Freezing Level
2500'
Saturday Night Freezing Level
2500'
(Easterly Flow *)
Sunday Morning Freezing Level
3000'
(Easterly Flow *)
Sunday Afternoon Freezing Level
3500'
(Easterly Flow *)
Sunday Evening Snow Level
3000'
Sunday Night Snow Level
2500'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2000'
Leavenworth Elevation
Saturday Evening Freezing Level
2500'
Saturday Night Freezing Level
2500'
(Easterly Flow *)
Sunday Morning Freezing Level
3500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
4000'
(Easterly Flow *)
Sunday Evening Snow Level
3000'
Sunday Night Snow Level
2500'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2000'
Stevens Pass Elevation
Saturday Evening Freezing Level
3000'
Saturday Night Freezing Level
3500'
(Easterly Flow *)
Sunday Morning Freezing Level
5500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
5500'
(Easterly Flow *)
Sunday Evening Snow Level
5000'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2000'
Snoqualmie Pass Elevation
Saturday Evening Freezing Level
3500'
Saturday Night Freezing Level
5500'
(Easterly Flow *)
Sunday Morning Freezing Level
7500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
6500'
(Easterly Flow *)
Sunday Evening Snow Level
5500'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
2500'
Mt. Rainier & Crystal Elevation
Saturday Evening Freezing Level
7500'
Saturday Night Freezing Level
7500'
(Easterly Flow *)
Sunday Morning Freezing Level
7500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
7000'
(Easterly Flow *)
Sunday Evening Snow Level
6500'
Sunday Night Snow Level
4000'
Monday Morning Snow Level
3500'
Monday Afternoon Snow Level
2500'
Mt. Hood Elevation
Saturday Evening Freezing Level
6500'
Saturday Night Freezing Level
8500'
(Easterly Flow *)
Sunday Morning Freezing Level
8500'
(Easterly Flow *)
Sunday Afternoon Freezing Level
8000'
(Easterly Flow *)
Sunday Evening Snow Level
7000'
Sunday Night Snow Level
5000'
Monday Morning Snow Level
3500'
Monday Afternoon Snow Level
3500'

* 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

Saturday Night Sunday Sunday Night Sunday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 0 0.50 - 0.75 LT 0.25
Mt Baker Ski Area 0 0 0.50 - 0.75 0.25 - 0.50
Washington Pass 0 0 0.25 0.25
Leavenworth 0 0 LT 0.10 0.25
Stevens Pass 0 0 LT 0.25 0.50 - 0.75
Snoqualmie Pass 0 0 0.25 0.50
Mission Ridge 0 0 LT 0.10 LT 0.25
Crystal Mt 0 0 0.25 - 0.50 0.25 - 0.50
Paradise 0 0 0.50 0.25 - 0.50
White Pass 0 0 LT 0.25 0.50
Mt Hood Meadows 0 0 LT 0.25 0.50 - 0.75
0 0 0.25 0.75
Hurricane Ridge Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.50 - 0.75
Sunday LT 0.25
Mt Baker Ski Area Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.50 - 0.75
Sunday 0.25 - 0.50
Washington Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.25
Sunday 0.25
Leavenworth Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.10
Sunday 0.25
Stevens Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.25
Sunday 0.50 - 0.75
Snoqualmie Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.25
Sunday 0.50
Mission Ridge Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.10
Sunday LT 0.25
Crystal Mt Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.25 - 0.50
Sunday 0.25 - 0.50
Paradise Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.50
Sunday 0.25 - 0.50
White Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.25
Sunday 0.50
Mt Hood Meadows Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.25
Sunday 0.50 - 0.75
Timberline Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0.25
Sunday 0.75

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Saturday Evening SE 0 - 10 S 0 - 10 SE 5 - 15 SE 0 - 10 SE 5 - 15
Saturday Night S 0 - 10 S 0 - 10 SE 10 - 20 SE 5 - 15 S 5 - 15
Sunday Morning SE 5 - 15 S 5 - 15 SE 10 - 20 SE 5 - 15 S 5 - 15
Hurricane Ridge Elevation
Saturday Evening SE 0 - 10
Saturday Night S 0 - 10
Sunday Morning SE 5 - 15
Sunday Afternoon S 15 - 25
Mt. Baker Elevation
Saturday Evening S 0 - 10
Saturday Night S 0 - 10
Sunday Morning S 5 - 15
Sunday Afternoon S 15 - 25
Stevens and Snoqualmie Pass Elevation
Saturday Evening SE 5 - 15
Saturday Night SE 10 - 20
Sunday Morning SE 10 - 20
Sunday Afternoon SE 10 - 20
Mt. Rainier Elevation
Saturday Evening SE 0 - 10
Saturday Night SE 5 - 15
Sunday Morning SE 5 - 15
Sunday Afternoon SE 5 - 15
Mt. Hood Elevation
Saturday Evening SE 5 - 15
Saturday Night S 5 - 15
Sunday Morning S 5 - 15
Sunday Afternoon SSW 5 - 15
Hurricane Ridge Direction - Speed
Saturday Evening SE 0 - 10
Saturday Night S 0 - 10
Sunday Morning SE 5 - 15
Sunday Afternoon S 15 - 25
Mt. Baker Direction - Speed
Saturday Evening S 0 - 10
Saturday Night S 0 - 10
Sunday Morning S 5 - 15
Sunday Afternoon S 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Saturday Evening SE 5 - 15
Saturday Night SE 10 - 20
Sunday Morning SE 10 - 20
Sunday Afternoon SE 10 - 20
Mt. Rainier Direction - Speed
Saturday Evening SE 0 - 10
Saturday Night SE 5 - 15
Sunday Morning SE 5 - 15
Sunday Afternoon SE 5 - 15
Mt. Hood Direction - Speed
Saturday Evening SE 5 - 15
Saturday Night S 5 - 15
Sunday Morning S 5 - 15
Sunday Afternoon SSW 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
Saturday Evening W 10 - 20 W 10 - 20 W 10 - 20 W 5 - 15 NW 0 - 10
Saturday Night SW 15 - 25 SW 10 - 20 SW 15 - 25 SW 10 - 20 SE 0 - 10
Sunday Morning SW 20 - 30 SW 20 - 30 SW 20 - 30 SW 10 - 20 S 10 - 20
Mt. Baker Direction - Speed
Saturday Evening W 10 - 20
Saturday Night SW 15 - 25
Sunday Morning SW 20 - 30
Sunday Afternoon SW 30 - 40
Washington Pass Direction - Speed
Saturday Evening W 10 - 20
Saturday Night SW 10 - 20
Sunday Morning SW 20 - 30
Sunday Afternoon SW 30 - 40
Stevens and Snoqualmie Pass Direction - Speed
Saturday Evening W 10 - 20
Saturday Night SW 15 - 25
Sunday Morning SW 20 - 30
Sunday Afternoon SW 25 - 35
Mt. Rainier Direction - Speed
Saturday Evening W 5 - 15
Saturday Night SW 10 - 20
Sunday Morning SW 10 - 20
Sunday Afternoon SW 25 - 35
Mt. Hood Direction - Speed
Saturday Evening NW 0 - 10
Saturday Night SE 0 - 10
Sunday Morning S 10 - 20
Sunday Afternoon SW 20 - 30

Extended Weather Synopsis for Sunday night through Sunday

Conditions should quickly dry out Monday night into Tuesday, and we are in for a potentially long stretch of dry weather relative to climatology for this time of year. Upper level ridging will build over the region in the extended with the jet stream shifting well north into Alaska and norther British Columbia. Surface high pressure will build offshore and strengthen as it slides into SW B.C. on Tuesday, setting up strong offshore flow. 

Beginning Tuesday night into Wednesday, freezing levels away from the Cascade Passes on the west side of the mountains will be quite high; 10,000-12,000 ft. Very strong temperature inversions will develop with cooler air along the lower slopes of the eastern Cascades, Mt. Hood and in and near the Cascade Passes and much warmer air at mid and higher elevations.   

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Monday Night Snow Level 1500' - 2500' 1500' - 2500' 2000' - 3000'
Tuesday Freezing Level 3000' - 4000' 3000' - 4000' 7500' - 8500'
Tuesday Night Freezing Level 9500' - 10500' 9000' - 10000' 9500' - 10500' *
Mt. Baker Elevation
Monday Night Snow Level
1500' - 2500'
Tuesday Freezing Level
3000' - 4000'
Tuesday Night Freezing Level
9500' - 10500'
(Easterly Flow *)
Wednesday Freezing Level
9500' - 10500'
(Easterly Flow *)
Snoqualmie Pass Elevation
Monday Night Snow Level
1500' - 2500'
Tuesday Freezing Level
3000' - 4000'
Tuesday Night Freezing Level
9000' - 10000'
(Easterly Flow *)
Wednesday Freezing Level
9000' - 10000'
(Easterly Flow *)
Mt. Hood Elevation
Monday Night Snow Level
2000' - 3000'
Tuesday Freezing Level
7500' - 8500'
Tuesday Night Freezing Level
9500' - 10500'
(Easterly Flow *)
Wednesday Freezing Level
9500' - 10500'
(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 Nov 28, 2020

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