Issued: 1:48 PM PDT Monday, April 6, 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 Monday night through Friday

We are sitting on the backside of a longwave trough with cool NW flow aloft. The trough itself is shearing apart between two upper low centers, one positioned over the Canadian Rockies, the other off the California coast. The main weather impact is that instability associated with the trough has shifted to the inland NW, so most of the cloud cover over the region is due to the buildup of cumulus/stratocumulus along the west slopes of the Cascades and Olympics with clearer conditions along the eastern slopes of the Cascades. 

A flat upper level ridge will begin to shift closer to the Pacific Northwest over the next two days with warmer air waiting to flood the region. The warming will be gradual and should only make inroads in the Mt. Hood area on Tuesday. Cool NW flow aloft will keep freezing levels relatively cool over Washington state one more day with a similarly mixed bag of cloud cover along the western slopes of the Cascades, similar to what we experienced Monday. For nearly all areas, alpine winds from the NW will increase and become strong tonight and continue through Tuesday. Look for breezing moderate westerly winds at Pass level again Tuesday afternoon and evening as onshore flow peaks. 

On Wednesday, the offshore upper level ridge will begin to amplify and shift closer to us, resulting in clearer skies and higher freezing levels across the board. Freezing levels across southern Washington and Mt. Hood should top out near or above 10,000'. Look for widespread mountain temperatures in the 40s and even 50s. 

Weather Forecast

Hurricane Ridge
Monday Night Partly cloudy with areas of low clouds.
Mt. Baker
Monday Night Partly to mostly cloudy with areas of low clouds. Strong alpine NW winds.
Washington Pass and Leavenworth
Monday Night Mostly clear. Strong alpine NW winds.
Stevens and Snoqualmie Pass
Monday Night Partly to mostly cloudy with areas of low clouds. Strong NW alpine winds. Moderate west winds at Pass level.
Mt. Rainier, Crystal and White Pass
Monday Night Partly to mostly cloudy with areas of low clouds.
Mt. Hood
Monday Night Partly to mostly cloudy with areas of low clouds.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Monday Evening Freezing Level 5000' 3500' 4000' 5000' 4500' 4500' 4500' 6000'
Monday Night Freezing Level 3500' 2500' 2500' 5000' 2500' 2500' 2500' 6500'
Tuesday Morning Freezing Level 4500' 4000' 4500' 5500' 4000' 4000' 4000' 7500'
Tuesday Afternoon Freezing Level 5500' 5000' 5500' 6000' 5000' 5000' 5500' 8500'
Tuesday Evening Freezing Level 5500' 4000' 4000' 5000' 4500' 4500' 6500' 8500'
Tuesday Night Freezing Level 6000' 3000' 3000' 4000' 3500' 3500' 7500' 8500'
Wednesday Morning Freezing Level 8000' 5500' 5000' 6000' 6500' 7000' 8000' 9500'
Hurricane Ridge Elevation
Monday Evening Freezing Level
5000'
Monday Night Freezing Level
3500'
Tuesday Morning Freezing Level
4500'
Tuesday Afternoon Freezing Level
5500'
Tuesday Evening Freezing Level
5500'
Tuesday Night Freezing Level
6000'
Wednesday Morning Freezing Level
8000'
Wednesday Afternoon Freezing Level
10000'
Mt. Baker Elevation
Monday Evening Freezing Level
3500'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
5000'
Tuesday Evening Freezing Level
4000'
Tuesday Night Freezing Level
3000'
Wednesday Morning Freezing Level
5500'
Wednesday Afternoon Freezing Level
7500'
Washington Pass Elevation
Monday Evening Freezing Level
4000'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4500'
Tuesday Afternoon Freezing Level
5500'
Tuesday Evening Freezing Level
4000'
Tuesday Night Freezing Level
3000'
Wednesday Morning Freezing Level
5000'
Wednesday Afternoon Freezing Level
7500'
Leavenworth Elevation
Monday Evening Freezing Level
5000'
Monday Night Freezing Level
5000'
Tuesday Morning Freezing Level
5500'
Tuesday Afternoon Freezing Level
6000'
Tuesday Evening Freezing Level
5000'
Tuesday Night Freezing Level
4000'
Wednesday Morning Freezing Level
6000'
Wednesday Afternoon Freezing Level
8000'
Stevens Pass Elevation
Monday Evening Freezing Level
4500'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
5000'
Tuesday Evening Freezing Level
4500'
Tuesday Night Freezing Level
3500'
Wednesday Morning Freezing Level
6500'
Wednesday Afternoon Freezing Level
8500'
Snoqualmie Pass Elevation
Monday Evening Freezing Level
4500'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
5000'
Tuesday Evening Freezing Level
4500'
Tuesday Night Freezing Level
3500'
Wednesday Morning Freezing Level
7000'
Wednesday Afternoon Freezing Level
9000'
Mt. Rainier & Crystal Elevation
Monday Evening Freezing Level
4500'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Freezing Level
5500'
Tuesday Evening Freezing Level
6500'
Tuesday Night Freezing Level
7500'
Wednesday Morning Freezing Level
8000'
Wednesday Afternoon Freezing Level
10000'
Mt. Hood Elevation
Monday Evening Freezing Level
6000'
Monday Night Freezing Level
6500'
Tuesday Morning Freezing Level
7500'
Tuesday Afternoon Freezing Level
8500'
Tuesday Evening Freezing Level
8500'
Tuesday Night Freezing Level
8500'
Wednesday Morning Freezing Level
9500'
Wednesday Afternoon Freezing Level
11000'

* 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

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Monday Evening SW 5 - 15 SW 10 - 20 W 15 - 25 W 10 - 20 W 10 - 20
Monday Night W 5 - 15 SW 10 - 20 W 10 - 20 W 5 - 15 NW 10 - 20
Tuesday Morning W 0 - 10 SW 5 - 15 NW 5 - 15 W 5 - 15 NW 10 - 20
Hurricane Ridge Elevation
Monday Evening SW 5 - 15
Monday Night W 5 - 15
Tuesday Morning W 0 - 10
Tuesday Afternoon W 5 - 15
Mt. Baker Elevation
Monday Evening SW 10 - 20
Monday Night SW 10 - 20
Tuesday Morning SW 5 - 15
Tuesday Afternoon WSW 10 - 20
Stevens and Snoqualmie Pass Elevation
Monday Evening W 15 - 25
Monday Night W 10 - 20
Tuesday Morning NW 5 - 15
Tuesday Afternoon NW 10 - 20
Mt. Rainier Elevation
Monday Evening W 10 - 20
Monday Night W 5 - 15
Tuesday Morning W 5 - 15
Tuesday Afternoon NW 10 - 20
Mt. Hood Elevation
Monday Evening W 10 - 20
Monday Night NW 10 - 20
Tuesday Morning NW 10 - 20
Tuesday Afternoon NW 15 - 25
Hurricane Ridge Direction - Speed
Monday Evening SW 5 - 15
Monday Night W 5 - 15
Tuesday Morning W 0 - 10
Tuesday Afternoon W 5 - 15
Mt. Baker Direction - Speed
Monday Evening SW 10 - 20
Monday Night SW 10 - 20
Tuesday Morning SW 5 - 15
Tuesday Afternoon WSW 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Monday Evening W 15 - 25
Monday Night W 10 - 20
Tuesday Morning NW 5 - 15
Tuesday Afternoon NW 10 - 20
Mt. Rainier Direction - Speed
Monday Evening W 10 - 20
Monday Night W 5 - 15
Tuesday Morning W 5 - 15
Tuesday Afternoon NW 10 - 20
Mt. Hood Direction - Speed
Monday Evening W 10 - 20
Monday Night NW 10 - 20
Tuesday Morning NW 10 - 20
Tuesday Afternoon NW 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
Monday Evening NW 25 - 35 NW 25 - 35 NW 30 - 40 NW 20 - 30 NW 10 - 20
Monday Night NW 30 - 40 NW 40 - 50 NW 40 - 50 NW 30 - 40 NW 20 - 30
Tuesday Morning NW 35 - 45 NW 35 - 45 NW 40 - 50 NW 30 - 40 NW 20 - 30
Mt. Baker Direction - Speed
Monday Evening NW 25 - 35
Monday Night NW 30 - 40
Tuesday Morning NW 35 - 45
Tuesday Afternoon NW 20 - 30
Washington Pass Direction - Speed
Monday Evening NW 25 - 35
Monday Night NW 40 - 50
Tuesday Morning NW 35 - 45
Tuesday Afternoon NW 20 - 30
Stevens and Snoqualmie Pass Direction - Speed
Monday Evening NW 30 - 40
Monday Night NW 40 - 50
Tuesday Morning NW 40 - 50
Tuesday Afternoon NW 35 - 45
Mt. Rainier Direction - Speed
Monday Evening NW 20 - 30
Monday Night NW 30 - 40
Tuesday Morning NW 30 - 40
Tuesday Afternoon NW 25 - 35
Mt. Hood Direction - Speed
Monday Evening NW 10 - 20
Monday Night NW 20 - 30
Tuesday Morning NW 20 - 30
Tuesday Afternoon NW 15 - 25

Extended Weather Synopsis for Friday night through Friday

The upper level ridge will shift into British Columbia on Thursday, allowing freezing levels and overall warmth to peak Wednesday night through Thursday. Forecast models disagree just how much high cloud cover will waft over the northern half of Washington State on Thursday. Beginning Thursday night, a slight cooling trend will start as a weak upper level disturbance upstream in NW flow aloft begins to flatten the upper level ridge. Depending on the speed of the upper level shortwave, scattered showers may develop over the Washington Cascades and Olympics by Friday afternoon while the Mt. Hood area stays relatively drier and warmer than areas further north.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Wednesday Night Freezing Level 9000' - 10000' 10000' - 11000' 11000' - 12000'
Thursday Freezing Level 9500' - 10500' 10500' - 11500' 11000' - 12000'
Thursday Night Freezing Level 6500' - 7500' 9000' - 10000' 11000' - 12000'
Mt. Baker Elevation
Wednesday Night Freezing Level
9000' - 10000'
Thursday Freezing Level
9500' - 10500'
Thursday Night Freezing Level
6500' - 7500'
Friday Freezing Level
6000' - 7000'
Snoqualmie Pass Elevation
Wednesday Night Freezing Level
10000' - 11000'
Thursday Freezing Level
10500' - 11500'
Thursday Night Freezing Level
9000' - 10000'
Friday Freezing Level
6500' - 7500'
Mt. Hood Elevation
Wednesday Night Freezing Level
11000' - 12000'
Thursday Freezing Level
11000' - 12000'
Thursday Night Freezing Level
11000' - 12000'
Friday Freezing Level
10000' - 11000'

* 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 Apr 5, 2020

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