Issued: 2:13 PM PST Friday, November 20, 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 Friday night through Sunday

The remnants of a weak front passing into central British Columbia continues to drape showers across the Olympics and the west slopes of the Cascades from about North Bend/I-90 and north to the Canadian border. Further south and east of Snoqualmie Pass there's a pretty rapid transition to clear skies this afternoon. The front will continue to sputter out light showers tonight in the same geographic areas as an upper-level ridge begins to build offshore. 

The upper-level ridge will amplify and pass inland on Saturday, bringing dry and milder conditions for the area. The Olympics and the west slopes of the Cascades from about Snoqualmie Pass and northward will be sandwiched between leftover low clouds from Friday night and periods of high clouds from the next incoming system moving in during the afternoon hours. Once again, areas further south and east, including Mt Rainier area, I-90 east of Snoqualmie, and down to Mt. Hood should see mostly sunshine on Saturday.  In these sunny areas, freezing levels will climb the highest; into the 7000-8000 ft range. Moderate easterly flow should develop in the Cascade Passes Saturday afternoon and continue Saturday night.  Saturday night, a slowly approaching frontal system will spread increasing clouds over the region. This weak frontal system now looks like it won't arrive until Sunday mid-day for western Washington. Little to no precipitation is likely to spill over to the east side on Sunday.  

Weather Forecast

Hurricane Ridge
Friday Night Cloudy with light rain and snow scattered showers.
Mt. Baker
Friday Night Light rain and snow showers.
Washington Pass and Leavenworth
Friday Night Mostly cloudy.
Stevens and Snoqualmie Pass
Friday Night Mostly cloudy with light rain and snow scattered showers. Light east wind at Pass level.
Mt. Rainier, Crystal and White Pass
Friday Night Mostly clear.
Mt. Hood
Friday 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
Friday Evening Snow Level 4000' 3500' 3500' 3500' 3500' 3500' 3500' 3500'
Friday Night Snow Level 4000' 3500' 3000' 3000' 3500' 3500' 3500' 4000'
Saturday Morning Freezing Level 4000' 3000' 2500' 3000' 3500' 3500' 3500' 5000'
Saturday Afternoon Freezing Level * 5500' 4500' 4500' 5000' 5500' 6500' 7000' 7500'
Saturday Evening Freezing Level * 6000' 4500' 4000' 3500' 5000' 6000' 6500' 8000'
Saturday Night Freezing Level * 7000' 4500' 2500' 2500' 4000' 6000' 6000' 8000'
Sunday Morning Snow Level * 3500' 3000' 2500' 2500' 3000' 3500' 4000' 4500'
Hurricane Ridge Elevation
Friday Evening Snow Level
4000'
Friday Night Snow Level
4000'
Saturday Morning Freezing Level
4000'
Saturday Afternoon Freezing Level
5500'
(Easterly Flow *)
Saturday Evening Freezing Level
6000'
(Easterly Flow *)
Saturday Night Freezing Level
7000'
(Easterly Flow *)
Sunday Morning Snow Level
3500'
(Easterly Flow *)
Sunday Afternoon Snow Level
3500'
Mt. Baker Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
3500'
Saturday Morning Freezing Level
3000'
Saturday Afternoon Freezing Level
4500'
(Easterly Flow *)
Saturday Evening Freezing Level
4500'
(Easterly Flow *)
Saturday Night Freezing Level
4500'
(Easterly Flow *)
Sunday Morning Snow Level
3000'
(Easterly Flow *)
Sunday Afternoon Snow Level
3000'
Washington Pass Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
3000'
Saturday Morning Freezing Level
2500'
Saturday Afternoon Freezing Level
4500'
(Easterly Flow *)
Saturday Evening Freezing Level
4000'
(Easterly Flow *)
Saturday Night Freezing Level
2500'
(Easterly Flow *)
Sunday Morning Snow Level
2500'
(Easterly Flow *)
Sunday Afternoon Snow Level
2500'
Leavenworth Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
3000'
Saturday Morning Freezing Level
3000'
Saturday Afternoon Freezing Level
5000'
(Easterly Flow *)
Saturday Evening Freezing Level
3500'
(Easterly Flow *)
Saturday Night Freezing Level
2500'
(Easterly Flow *)
Sunday Morning Snow Level
2500'
(Easterly Flow *)
Sunday Afternoon Snow Level
2000'
Stevens Pass Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
3500'
Saturday Morning Freezing Level
3500'
Saturday Afternoon Freezing Level
5500'
(Easterly Flow *)
Saturday Evening Freezing Level
5000'
(Easterly Flow *)
Saturday Night Freezing Level
4000'
(Easterly Flow *)
Sunday Morning Snow Level
3000'
(Easterly Flow *)
Sunday Afternoon Snow Level
2500'
Snoqualmie Pass Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
3500'
Saturday Morning Freezing Level
3500'
Saturday Afternoon Freezing Level
6500'
(Easterly Flow *)
Saturday Evening Freezing Level
6000'
(Easterly Flow *)
Saturday Night Freezing Level
6000'
(Easterly Flow *)
Sunday Morning Snow Level
3500'
(Easterly Flow *)
Sunday Afternoon Snow Level
2500'
Mt. Rainier & Crystal Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
3500'
Saturday Morning Freezing Level
3500'
Saturday Afternoon Freezing Level
7000'
(Easterly Flow *)
Saturday Evening Freezing Level
6500'
(Easterly Flow *)
Saturday Night Freezing Level
6000'
(Easterly Flow *)
Sunday Morning Snow Level
4000'
(Easterly Flow *)
Sunday Afternoon Snow Level
3500'
Mt. Hood Elevation
Friday Evening Snow Level
3500'
Friday Night Snow Level
4000'
Saturday Morning Freezing Level
5000'
Saturday Afternoon Freezing Level
7500'
(Easterly Flow *)
Saturday Evening Freezing Level
8000'
(Easterly Flow *)
Saturday Night Freezing Level
8000'
(Easterly Flow *)
Sunday Morning Snow Level
4500'
(Easterly Flow *)
Sunday 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

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

Free Winds at 5000' (mph)

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

Extended Weather Synopsis for Sunday night through Tuesday

A quick moving and slightly stronger frontal system will follow on the Sunday system's heels...arriving Sunday night into Monday.  This system may produce 0.25-0.50" of water equivalent along the west slopes of the Cascades with less elsewhere. 

Snow levels will be back on the rise Monday night and Tuesday as a much stronger Pacific frontal system winds up in the Gulf of Alaska. Warm frontal precipitation will brush the area during this period but it is unclear how heavy warm frontal precipitation will be over the area. While we wait for a strong cold front to arrive late Tuesday or Tuesday night, snow levels will continue to stay elevated while we are in the warm sector of the storm. 

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Sunday Night Snow Level 2000' - 3000' 2000' - 3000' 2500' - 3500'
Monday Snow Level 2500' - 3500' 3000' - 4000' 3500' - 4500'
Monday Night Snow Level 3500' - 4500' 4000' - 5000' 4500' - 5500' *
Mt. Baker Elevation
Sunday Night Snow Level
2000' - 3000'
Monday Snow Level
2500' - 3500'
Monday Night Snow Level
3500' - 4500'
(Easterly Flow *)
Tuesday Snow Level
5000' - 6000'
(Easterly Flow *)
Snoqualmie Pass Elevation
Sunday Night Snow Level
2000' - 3000'
Monday Snow Level
3000' - 4000'
Monday Night Snow Level
4000' - 5000'
(Easterly Flow *)
Tuesday Snow Level
5500' - 6500'
(Easterly Flow *)
Mt. Hood Elevation
Sunday Night Snow Level
2500' - 3500'
Monday Snow Level
3500' - 4500'
Monday Night Snow Level
4500' - 5500'
(Easterly Flow *)
Tuesday Snow Level
5500' - 6500'
(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 19, 2020

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