Issued: 2:17 PM PST Tuesday, November 24, 2020
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 Tuesday night through Tuesday

A sharp cold front with strong wind shear, an intense squall line and moderate to locally strong southerly winds enters the region from the WNW on Tuesday afternoon. The precipitation and southerly winds should peak early evening on Tuesday as the front crosses the Cascades and snow lines drop rapidly from around 4000-5000 ft prior to the front to around 2000-2500 ft by Wednesday morning as winds shift WSW. Overnight Tuesday, the precipitation should become significantly lighter and showery, with the heaviest precipitation focused on the southern Cascades and in convergence potentially setting up between the mountain loop and Snoqualmie Pass. Snoqualmie pass should see a transition from rain to snow during the evening, while Stevens pass should stay cool enough for all snow. Many regions across the west slopes of the Cascades should pick up 3-10" of snow Tuesday night.

Wednesday remains cool with snow levels near or below pass levels. The upper trough will bring additional instability, enhancing light to moderate snow shower activity over the region.

The trough shifts east over our region Wednesday night as a ridge slides E into our nearshore waters. The ridge ridge flattens slightly as it moves over our region on Thursday, but it is likely to give us a dry and milder day, shunting a subtropical moisture feed north into British Columbia. Cloud cover is likely to remain in northern parts of the forecast region.

Weather Forecast

Hurricane Ridge
Tuesday Night Light snow showers. Strong cooling in the evening. Moderate winds becoming light.
Mt. Baker
Tuesday Night Moderate to heavy snow in the early evening, then light snow showers. Rapidly cooling temperatures. Moderate winds with strong gusts early, then decreasing.
Washington Pass and Leavenworth
Tuesday Night Decreasing moderate snow in the evening, then light snow showers after midnight. Rapidly cooling temperatures. Moderate winds with strong gusts early, then decreasing.
Stevens and Snoqualmie Pass
Tuesday Night Moderate rain and snow in the evening, then becoming light to moderate snow showers, heaviest in convergence. Moderate 5000 ft winds with strong gusts early, then decreasing. Light E pass-level winds in the early evening rapidly switching W.
Mt. Rainier, Crystal and White Pass
Tuesday Night Rain and snow in the evening, becoming snow showers after midnight, moderate intensity at Paradise and light at Crystal and White Passes. Moderate winds with strong gusts early, then decreasing.
Mt. Hood
Tuesday Night Moderate snow becoming light to moderate snow showers after midnight. Rapidly cooling temperatures. Moderate winds with strong gusts early, then decreasing.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Evening Snow Level 2500' 3000' 3000' 3500' 3500' 4000' 4000' 5000'
Tuesday Night Snow Level 2000' 2000' 2000' 2500' 2000' 2000' 2000' 2500'
Wednesday Morning Snow Level 2500' 1500' 1500' 2000' 2000' 2000' 2000' 2500'
Wednesday Afternoon Snow Level 3000' 2500' 2500' 3000' 2500' 2500' 3000' 3000'
Wednesday Evening Snow Level 3000' 2000' 2000' 2500' 2500' 2500' 2500' 3000'
Wednesday Night Snow Level 2500' 2000' 2000' 2000' 2500' 2500' 2500' 3000'
Thursday Morning Freezing Level 4000' 3000' 2500' 3000' 3000' 3500' 3000' 4000'
Hurricane Ridge Elevation
Tuesday Evening Snow Level
2500'
Tuesday Night Snow Level
2000'
Wednesday Morning Snow Level
2500'
Wednesday Afternoon Snow Level
3000'
Wednesday Evening Snow Level
3000'
Wednesday Night Snow Level
2500'
Thursday Morning Freezing Level
4000'
Thursday Afternoon Freezing Level
4500'
Mt. Baker Elevation
Tuesday Evening Snow Level
3000'
Tuesday Night Snow Level
2000'
Wednesday Morning Snow Level
1500'
Wednesday Afternoon Snow Level
2500'
Wednesday Evening Snow Level
2000'
Wednesday Night Snow Level
2000'
Thursday Morning Freezing Level
3000'
Thursday Afternoon Freezing Level
3000'
Washington Pass Elevation
Tuesday Evening Snow Level
3000'
Tuesday Night Snow Level
2000'
Wednesday Morning Snow Level
1500'
Wednesday Afternoon Snow Level
2500'
Wednesday Evening Snow Level
2000'
Wednesday Night Snow Level
2000'
Thursday Morning Freezing Level
2500'
Thursday Afternoon Freezing Level
3000'
Leavenworth Elevation
Tuesday Evening Snow Level
3500'
Tuesday Night Snow Level
2500'
Wednesday Morning Snow Level
2000'
Wednesday Afternoon Snow Level
3000'
Wednesday Evening Snow Level
2500'
Wednesday Night Snow Level
2000'
Thursday Morning Freezing Level
3000'
Thursday Afternoon Freezing Level
4000'
Stevens Pass Elevation
Tuesday Evening Snow Level
3500'
Tuesday Night Snow Level
2000'
Wednesday Morning Snow Level
2000'
Wednesday Afternoon Snow Level
2500'
Wednesday Evening Snow Level
2500'
Wednesday Night Snow Level
2500'
Thursday Morning Freezing Level
3000'
Thursday Afternoon Freezing Level
3500'
Snoqualmie Pass Elevation
Tuesday Evening Snow Level
4000'
Tuesday Night Snow Level
2000'
Wednesday Morning Snow Level
2000'
Wednesday Afternoon Snow Level
2500'
Wednesday Evening Snow Level
2500'
Wednesday Night Snow Level
2500'
Thursday Morning Freezing Level
3500'
Thursday Afternoon Freezing Level
3500'
Mt. Rainier & Crystal Elevation
Tuesday Evening Snow Level
4000'
Tuesday Night Snow Level
2000'
Wednesday Morning Snow Level
2000'
Wednesday Afternoon Snow Level
3000'
Wednesday Evening Snow Level
2500'
Wednesday Night Snow Level
2500'
Thursday Morning Freezing Level
3000'
Thursday Afternoon Freezing Level
4000'
Mt. Hood Elevation
Tuesday Evening Snow Level
5000'
Tuesday Night Snow Level
2500'
Wednesday Morning Snow Level
2500'
Wednesday Afternoon Snow Level
3000'
Wednesday Evening Snow Level
3000'
Wednesday Night Snow Level
3000'
Thursday Morning Freezing Level
4000'
Thursday Afternoon Freezing Level
4500'

* 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

Tuesday Night Tuesday Tuesday Night Tuesday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge LT 0.25 LT 0.10 0 0
Mt Baker Ski Area 0.25 - 0.50 LT 0.10 0 0
Washington Pass 0.25 - 0.50 LT 0.10 0 0
Leavenworth LT 0.10 0 0 0
Stevens Pass 0.50 - 0.75 0.25 - 0.50 0 0
Snoqualmie Pass 0.50 0.50 0 0
Mission Ridge LT 0.25 LT 0.10 0 0
Crystal Mt 0.25 LT 0.10 0 0
Paradise 0.75 0.50 - 0.75 LT 0.10 0
White Pass 0.50 0.25 0 0
Mt Hood Meadows 0.50 - 0.75 0.75 LT 0.25 0
0.75 0.75 -1.00 0.25 0
Hurricane Ridge Precipitation Forecast
Tuesday Night LT 0.25
Tuesday LT 0.10
Tuesday Night 0
Tuesday 0
Mt Baker Ski Area Precipitation Forecast
Tuesday Night 0.25 - 0.50
Tuesday LT 0.10
Tuesday Night 0
Tuesday 0
Washington Pass Precipitation Forecast
Tuesday Night 0.25 - 0.50
Tuesday LT 0.10
Tuesday Night 0
Tuesday 0
Leavenworth Precipitation Forecast
Tuesday Night LT 0.10
Tuesday 0
Tuesday Night 0
Tuesday 0
Stevens Pass Precipitation Forecast
Tuesday Night 0.50 - 0.75
Tuesday 0.25 - 0.50
Tuesday Night 0
Tuesday 0
Snoqualmie Pass Precipitation Forecast
Tuesday Night 0.50
Tuesday 0.50
Tuesday Night 0
Tuesday 0
Mission Ridge Precipitation Forecast
Tuesday Night LT 0.25
Tuesday LT 0.10
Tuesday Night 0
Tuesday 0
Crystal Mt Precipitation Forecast
Tuesday Night 0.25
Tuesday LT 0.10
Tuesday Night 0
Tuesday 0
Paradise Precipitation Forecast
Tuesday Night 0.75
Tuesday 0.50 - 0.75
Tuesday Night LT 0.10
Tuesday 0
White Pass Precipitation Forecast
Tuesday Night 0.50
Tuesday 0.25
Tuesday Night 0
Tuesday 0
Mt Hood Meadows Precipitation Forecast
Tuesday Night 0.50 - 0.75
Tuesday 0.75
Tuesday Night LT 0.25
Tuesday 0
Timberline Precipitation Forecast
Tuesday Night 0.75
Tuesday 0.75 -1.00
Tuesday Night 0.25
Tuesday 0

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Evening WSW 10 - 20 SW 15 - 25 SW 15 - 25 SW 15 - 25 WSW 15 - 25
Tuesday Night WSW 5 - 15 WSW 5 - 15 W 15 - 25 W 15 - 25 W 15 - 25
Wednesday Morning WSW 0 - 10 WSW 5 - 15 W 10 - 20 WSW 10 - 20 WSW 15 - 25
Hurricane Ridge Elevation
Tuesday Evening WSW 10 - 20
Tuesday Night WSW 5 - 15
Wednesday Morning WSW 0 - 10
Wednesday Afternoon VAR 0 - 10
Mt. Baker Elevation
Tuesday Evening SW 15 - 25
Tuesday Night WSW 5 - 15
Wednesday Morning WSW 5 - 15
Wednesday Afternoon WSW 0 - 10
Stevens and Snoqualmie Pass Elevation
Tuesday Evening SW 15 - 25
Tuesday Night W 15 - 25
Wednesday Morning W 10 - 20
Wednesday Afternoon W 5 - 15
Mt. Rainier Elevation
Tuesday Evening SW 15 - 25
Tuesday Night W 15 - 25
Wednesday Morning WSW 10 - 20
Wednesday Afternoon W 5 - 15
Mt. Hood Elevation
Tuesday Evening WSW 15 - 25
Tuesday Night W 15 - 25
Wednesday Morning WSW 15 - 25
Wednesday Afternoon W 15 - 25
Hurricane Ridge Direction - Speed
Tuesday Evening WSW 10 - 20
Tuesday Night WSW 5 - 15
Wednesday Morning WSW 0 - 10
Wednesday Afternoon VAR 0 - 10
Mt. Baker Direction - Speed
Tuesday Evening SW 15 - 25
Tuesday Night WSW 5 - 15
Wednesday Morning WSW 5 - 15
Wednesday Afternoon WSW 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Evening SW 15 - 25
Tuesday Night W 15 - 25
Wednesday Morning W 10 - 20
Wednesday Afternoon W 5 - 15
Mt. Rainier Direction - Speed
Tuesday Evening SW 15 - 25
Tuesday Night W 15 - 25
Wednesday Morning WSW 10 - 20
Wednesday Afternoon W 5 - 15
Mt. Hood Direction - Speed
Tuesday Evening WSW 15 - 25
Tuesday Night W 15 - 25
Wednesday Morning WSW 15 - 25
Wednesday Afternoon W 15 - 25

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
Tuesday Evening SW 30 - 40 SW 25 - 35 WSW 30 - 40 WSW 25 - 35 WSW 40 - 55
Tuesday Night W 20 - 30 W 25 - 35 W 25 - 35 W 25 - 35 W 30 - 40
Wednesday Morning W 10 - 20 W 10 - 20 W 20 - 30 W 20 - 30 W 30 - 40
Mt. Baker Direction - Speed
Tuesday Evening SW 30 - 40
Tuesday Night W 20 - 30
Wednesday Morning W 10 - 20
Wednesday Afternoon WNW 5 - 15
Washington Pass Direction - Speed
Tuesday Evening SW 25 - 35
Tuesday Night W 25 - 35
Wednesday Morning W 10 - 20
Wednesday Afternoon WNW 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Evening WSW 30 - 40
Tuesday Night W 25 - 35
Wednesday Morning W 20 - 30
Wednesday Afternoon WNW 15 - 25
Mt. Rainier Direction - Speed
Tuesday Evening WSW 25 - 35
Tuesday Night W 25 - 35
Wednesday Morning W 20 - 30
Wednesday Afternoon WNW 15 - 25
Mt. Hood Direction - Speed
Tuesday Evening WSW 40 - 55
Tuesday Night W 30 - 40
Wednesday Morning W 30 - 40
Wednesday Afternoon WNW 25 - 35

Extended Weather Synopsis for Tuesday night through Tuesday

The mild ridge of high pressure lingers over our region Thursday night and eventually breaks down late in the day on Friday. Models have some light amounts of moisture brushing northern Washington Thursday night. On Friday, clouds should linger in the north, but central and southern parts of the region will experience a very mild day. Freezing levels may get as high as 10,000 ft in the Mt. Hood area.

A cold front is expected late Friday night into Saturday with a quick shot of rain and snow and some cooling. Chances of accumulating snows are better in the northern parts of the forecast region where temperatures will be much cooler throughout the storm, with accumulations likely at mid and upper elevations elsewhere.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Thursday Night Snow Level 2500' - 3500' 3000' - 4000' 5000' - 6000'
Friday Freezing Level 3500' - 4500' 6000' - 8000' 8000' - 10000'
Friday Night Snow Level 2500' - 3500' 4000' - 6000' 7500' - 9500'
Mt. Baker Elevation
Thursday Night Snow Level
2500' - 3500'
Friday Freezing Level
3500' - 4500'
Friday Night Snow Level
2500' - 3500'
Saturday Snow Level
2000' - 3000'
Snoqualmie Pass Elevation
Thursday Night Snow Level
3000' - 4000'
Friday Freezing Level
6000' - 8000'
Friday Night Snow Level
4000' - 6000'
Saturday Snow Level
2500' - 3500'
Mt. Hood Elevation
Thursday Night Snow Level
5000' - 6000'
Friday Freezing Level
8000' - 10000'
Friday Night Snow Level
7500' - 9500'
Saturday 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 Nov 23, 2020

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