Issued: 2:20 PM PST Saturday, November 21, 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 Monday

After a beautiful Saturday across the Pacific Northwest, high clouds from an approaching frontal system have begun to intrude over the Olympics and north Cascades this afternoon. High clouds will continue to push inland tonight ahead of the frontal system. This system will take its time to move inland on Sunday, leaving us with a dry morning before disspating over the area Sunday afternoon, bring some light precipitation mainly to the northwest Cascades and Olympics and dribs and drabs elsewhere. Freezing levels will stay elevated through tonight before coming back down to 3000-4000' with the onset of precipitation Sunday.  Easterly flow through the Passes will keep a good east breeze going until offshore gradients begin to relax tomorrow morning. 

A quick moving frontal system Sunday night into Monday morning will bring around 0.25" of water to the west slopes of the Cascades and Mt. Hood. This system will quickly exit without much fanfare on Monday. 

 

Weather Forecast

Hurricane Ridge
Saturday Night Partly cloudy with periods of high clouds in the evening, high overcast after midnight.
Mt. Baker
Saturday Night Partly cloudy with periods of high clouds in the evening, high overcast after midnight.
Washington Pass and Leavenworth
Saturday Night Partly cloudy with periods of high clouds in the evening, high overcast after midnight.
Stevens and Snoqualmie Pass
Saturday Night Mostly clear with periods of high clouds in the evening, high overcast after midnight. Moderate east winds at Pass level.
Mt. Rainier, Crystal and White Pass
Saturday Night Mostly clear with periods of high clouds in the evening, high overcast after midnight.
Mt. Hood
Saturday Night High overcast with filtered sunshine in the morning becoming cloudy in the afternoon with a slight chance of light rain or snow.

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 * 7000' 6500' 6500' 6500' 7000' 7000' 8000' 8500'
Saturday Night Freezing Level * 6500' 6500' 5500' 5000' 5500' 6500' 7000' 8000'
Sunday Morning Freezing Level * 6000' 6000' 4000' 4000' 4500' 5500' 6500' 7500'
Sunday Afternoon Snow Level 3500' 3000' 2500' 3000' 3000' 3000' 3500' 4000'
Sunday Evening Snow Level 3000' 2500' 2500' 3000' 2500' 3000' 3500' 4000'
Sunday Night Snow Level 3000' 2000' 2000' 2000' 2000' 2500' 3000' 3500'
Monday Morning Snow Level 3000' 2000' 2000' 2000' 2000' 2500' 3000' 3500'
Hurricane Ridge Elevation
Saturday Evening Freezing Level
7000'
(Easterly Flow *)
Saturday Night Freezing Level
6500'
(Easterly Flow *)
Sunday Morning Freezing Level
6000'
(Easterly Flow *)
Sunday Afternoon Snow Level
3500'
Sunday Evening Snow Level
3000'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
3000'
Mt. Baker Elevation
Saturday Evening Freezing Level
6500'
(Easterly Flow *)
Saturday Night Freezing Level
6500'
(Easterly Flow *)
Sunday Morning Freezing Level
6000'
(Easterly Flow *)
Sunday Afternoon Snow Level
3000'
Sunday Evening Snow Level
2500'
Sunday Night Snow Level
2000'
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
2500'
Washington Pass Elevation
Saturday Evening Freezing Level
6500'
(Easterly Flow *)
Saturday Night Freezing Level
5500'
(Easterly Flow *)
Sunday Morning Freezing Level
4000'
(Easterly Flow *)
Sunday Afternoon Snow Level
2500'
Sunday Evening Snow Level
2500'
Sunday Night Snow Level
2000'
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
2500'
Leavenworth Elevation
Saturday Evening Freezing Level
6500'
(Easterly Flow *)
Saturday Night Freezing Level
5000'
(Easterly Flow *)
Sunday Morning Freezing Level
4000'
(Easterly Flow *)
Sunday Afternoon Snow Level
3000'
Sunday Evening Snow Level
3000'
Sunday Night Snow Level
2000'
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
2500'
Stevens Pass Elevation
Saturday Evening Freezing Level
7000'
(Easterly Flow *)
Saturday Night Freezing Level
5500'
(Easterly Flow *)
Sunday Morning Freezing Level
4500'
(Easterly Flow *)
Sunday Afternoon Snow Level
3000'
Sunday Evening Snow Level
2500'
Sunday Night Snow Level
2000'
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
2500'
Snoqualmie Pass Elevation
Saturday Evening Freezing Level
7000'
(Easterly Flow *)
Saturday Night Freezing Level
6500'
(Easterly Flow *)
Sunday Morning Freezing Level
5500'
(Easterly Flow *)
Sunday Afternoon Snow Level
3000'
Sunday Evening Snow Level
3000'
Sunday Night Snow Level
2500'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
3000'
Mt. Rainier & Crystal Elevation
Saturday Evening Freezing Level
8000'
(Easterly Flow *)
Saturday Night Freezing Level
7000'
(Easterly Flow *)
Sunday Morning Freezing Level
6500'
(Easterly Flow *)
Sunday Afternoon Snow Level
3500'
Sunday Evening Snow Level
3500'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
3500'
Mt. Hood Elevation
Saturday Evening Freezing Level
8500'
(Easterly Flow *)
Saturday Night Freezing Level
8000'
(Easterly Flow *)
Sunday Morning Freezing Level
7500'
(Easterly Flow *)
Sunday Afternoon Snow Level
4000'
Sunday Evening Snow Level
4000'
Sunday Night Snow Level
3500'
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 Monday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 LT 0.10 LT 0.25 LT 0.10
Mt Baker Ski Area 0 LT 0.10 LT 0.25 LT 0.10
Washington Pass 0 0 LT 0.10 LT 0.10
Leavenworth 0 0 0 0
Stevens Pass 0 0 LT 0.25 LT 0.10
Snoqualmie Pass 0 LT 0.10 LT 0.25 LT 0.25
Mission Ridge 0 0 LT 0.10 LT 0.10
Crystal Mt 0 0 LT 0.10 LT 0.10
Paradise 0 LT 0.10 0.25 0.25
White Pass 0 0 LT 0.10 LT 0.25
Mt Hood Meadows 0 LT 0.10 LT 0.25 LT 0.25
0 LT 0.10 LT 0.25 0.25
Hurricane Ridge Precipitation Forecast
Saturday Night 0
Sunday LT 0.10
Sunday Night LT 0.25
Monday LT 0.10
Mt Baker Ski Area Precipitation Forecast
Saturday Night 0
Sunday LT 0.10
Sunday Night LT 0.25
Monday LT 0.10
Washington Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.10
Monday LT 0.10
Leavenworth Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night 0
Monday 0
Stevens Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.25
Monday LT 0.10
Snoqualmie Pass Precipitation Forecast
Saturday Night 0
Sunday LT 0.10
Sunday Night LT 0.25
Monday LT 0.25
Mission Ridge Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.10
Monday LT 0.10
Crystal Mt Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.10
Monday LT 0.10
Paradise Precipitation Forecast
Saturday Night 0
Sunday LT 0.10
Sunday Night 0.25
Monday 0.25
White Pass Precipitation Forecast
Saturday Night 0
Sunday 0
Sunday Night LT 0.10
Monday LT 0.25
Mt Hood Meadows Precipitation Forecast
Saturday Night 0
Sunday LT 0.10
Sunday Night LT 0.25
Monday LT 0.25
Timberline Precipitation Forecast
Saturday Night 0
Sunday LT 0.10
Sunday Night LT 0.25
Monday 0.25

Free Winds at 5000' (mph)

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

Extended Weather Synopsis for Monday night through Wednesday

A deep low pressure system in the Gulf of Alaska will begin to brush the area late Monday night and Tuesday with warm frontal precpitation. Currently forecast models indicate little precipitation will impact the area outside of the Olympics and the northwest Cascades including Mt Baker area. Even then, precipitation values during the day on Tuesday don't look to impressive yet but this is worth keeping an eye on. A warming trend will take place on Tuesday but this won't drive snow levels too high before the associated cold front comes crashing through sometime Tuesday night.  Snow levels will drop along as precipitation and winds increase heading into Wednesday. Wednesday looks like a good post-frontal flow to add snow accumulations in the form of showers along the west slopes of the Cascades and Mt. Hood. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Monday Night Snow Level 2000' - 3000' 2000' - 3000' 2500' - 3500' *
Tuesday Snow Level 4000' - 5000' 4000' - 5000' 4500' - 5500' *
Tuesday Night Snow Level 2000' - 3000' 2500' - 3500' 3000' - 4000'
Mt. Baker Elevation
Monday Night Snow Level
2000' - 3000'
(Easterly Flow *)
Tuesday Snow Level
4000' - 5000'
(Easterly Flow *)
Tuesday Night Snow Level
2000' - 3000'
Wednesday Snow Level
2000' - 3000'
Snoqualmie Pass Elevation
Monday Night Snow Level
2000' - 3000'
(Easterly Flow *)
Tuesday Snow Level
4000' - 5000'
(Easterly Flow *)
Tuesday Night Snow Level
2500' - 3500'
Wednesday Snow Level
2500' - 3500'
Mt. Hood Elevation
Monday Night Snow Level
2500' - 3500'
(Easterly Flow *)
Tuesday Snow Level
4500' - 5500'
(Easterly Flow *)
Tuesday Night Snow Level
3000' - 4000'
Wednesday Snow Level
3000' - 4000'

* 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 20, 2020

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