Issued: 6:08 PM PDT Monday, March 9, 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 Monday night through Tuesday

Updated to include sensible weather information.

A weak ridge remains over the region through Tuesday morning, maintaining light winds, mostly clear/sunny skies, and large diurnal differences in temperatures.

A system dropping down from the Gulf of Alaska on NW flow, sending a good chunk of its energy into British Columbia. It should bring increasing high clouds to northern Washington State Monday night into Tuesday morning. Precipitation follows late Tuesday morning and increases through the end of the day for the west slopes of the Cascades north of Snoqualmie Pass and the Olympic Mountains (with Hurricane Ridge largely rain-shadowed). Light to moderate precipitation initially focuses on the West North Cascades, but shifts southward to include the West Central Cascades Tuesday evening and all of the Cascades overnight, while beginning to let up in the north. Precipitation should be light in all areas by Wednesday morning. Expect some convergence in the Central Cascades Tuesday night, shifting southward into the Snoqualmie Vicinity on Wednesday morning. Snow levels should generally be in the 2000-4000 ft range, peaking late Tuesday evening with subtle warming, and then cooling Tuesday night with a cold frontal passage. Snoqualmie Pass level should see rain Tuesday night with a changeover to snow early Wednesday morning.

Perhaps the biggest story with this system will be the westerly winds. Moderate westerlies pick up out ahead of the storm on Tuesday and should be strong in the alpine by Tuesday evening from White Pass northward. Winds accelerate downslope and should be particularly strong east of the Cascade Crest. Winds should gradually decrease on Wednesday as the system moves away.

The region dries out Wednesday afternoon as a large offshore ridge edges into the region from the west.

Weather Forecast

Hurricane Ridge
Monday Night Mostly clear with high clouds in the evening. Clouds increasing, lowering and thickening after midnight.
Mt. Baker
Monday Night Mostly clear with high clouds in the evening. Clouds increasing, lowering and thickening after midnight.
Washington Pass and Leavenworth
Monday Night Mostly clear with thin high clouds in the evening; Mid-level clouds increasing in the northern areas (near Washington Pass) by morning.
Stevens and Snoqualmie Pass
Monday Night Mostly clear with high clouds increasing by morning.
Mt. Rainier, Crystal and White Pass
Monday Night Mostly clear with high clouds increasing by morning.
Mt. Hood
Monday Night 2020-03-09 Night: Mostly clear and cool.... for Mt. Hood Monday Night, Mar 9 Mostly clear and cool.

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 3000' 2500' 2500' 3500' 3000' 3500' 4000' 4500'
Monday Night Freezing Level 3000' 1500' 1000' 2000' 2000' 2500' 2500' 3500'
Tuesday Morning Freezing Level 3000' 2000' 15000' 3000' 2000' 2500' 3000' 4000'
Tuesday Afternoon Snow Level 3000' 2000' 3000' 4000' 3500' 3500' 3500' 5000'
Tuesday Evening Snow Level 4000' 2500' 3000' 3500' 3000' 3500' 4000' 6000'
Tuesday Night Snow Level 4000' 3000' 2500' 3500' 3000' 3500' 4000' 5500'
Wednesday Morning Snow Level 2000' 2000' 2500' 3500' 3000' 3000' 3500' 4500'
Hurricane Ridge Elevation
Monday Evening Freezing Level
3000'
Monday Night Freezing Level
3000'
Tuesday Morning Freezing Level
3000'
Tuesday Afternoon Snow Level
3000'
Tuesday Evening Snow Level
4000'
Tuesday Night Snow Level
4000'
Wednesday Morning Snow Level
2000'
Wednesday Afternoon Snow Level
3500'
Mt. Baker Elevation
Monday Evening Freezing Level
2500'
Monday Night Freezing Level
1500'
Tuesday Morning Freezing Level
2000'
Tuesday Afternoon Snow Level
2000'
Tuesday Evening Snow Level
2500'
Tuesday Night Snow Level
3000'
Wednesday Morning Snow Level
2000'
Wednesday Afternoon Snow Level
3000'
Washington Pass Elevation
Monday Evening Freezing Level
2500'
Monday Night Freezing Level
1000'
Tuesday Morning Freezing Level
15000'
Tuesday Afternoon Snow Level
3000'
Tuesday Evening Snow Level
3000'
Tuesday Night Snow Level
2500'
Wednesday Morning Snow Level
2500'
Wednesday Afternoon Snow Level
3500'
Leavenworth Elevation
Monday Evening Freezing Level
3500'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
3000'
Tuesday Afternoon Snow Level
4000'
Tuesday Evening Snow Level
3500'
Tuesday Night Snow Level
3500'
Wednesday Morning Snow Level
3500'
Wednesday Afternoon Snow Level
4000'
Stevens Pass Elevation
Monday Evening Freezing Level
3000'
Monday Night Freezing Level
2000'
Tuesday Morning Freezing Level
2000'
Tuesday Afternoon Snow Level
3500'
Tuesday Evening Snow Level
3000'
Tuesday Night Snow Level
3000'
Wednesday Morning Snow Level
3000'
Wednesday Afternoon Snow Level
3500'
Snoqualmie Pass Elevation
Monday Evening Freezing Level
3500'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
2500'
Tuesday Afternoon Snow Level
3500'
Tuesday Evening Snow Level
3500'
Tuesday Night Snow Level
3500'
Wednesday Morning Snow Level
3000'
Wednesday Afternoon Snow Level
3500'
Mt. Rainier & Crystal Elevation
Monday Evening Freezing Level
4000'
Monday Night Freezing Level
2500'
Tuesday Morning Freezing Level
3000'
Tuesday Afternoon Snow Level
3500'
Tuesday Evening Snow Level
4000'
Tuesday Night Snow Level
4000'
Wednesday Morning Snow Level
3500'
Wednesday Afternoon Snow Level
4000'
Mt. Hood Elevation
Monday Evening Freezing Level
4500'
Monday Night Freezing Level
3500'
Tuesday Morning Freezing Level
4000'
Tuesday Afternoon Snow Level
5000'
Tuesday Evening Snow Level
6000'
Tuesday Night Snow Level
5500'
Wednesday Morning Snow Level
4500'
Wednesday Afternoon Snow 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

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

Free Winds at 5000' (mph)

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

Extended Weather Synopsis for Tuesday night through Tuesday

The offshore ridge dominates the picture Wednesday night and Thursday bringing fair weather. Clouds increase Thursday night ahead of a sharp upper low that should bring increasing widespread snow to the Washington Cascades and Olympics on Friday with rapidly cooling temperatures dropping snow levels to just above sea level.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Wednesday Night Freezing Level 1000' - 2500' 1500' - 3000' 3000' - 4500'
Thursday Freezing Level 1000' - 3000' 1500' - 3500' 3000' - 5000'
Thursday Night Snow Level 15000' - 2500' 2000' - 3000' 3000' - 4000'
Mt. Baker Elevation
Wednesday Night Freezing Level
1000' - 2500'
Thursday Freezing Level
1000' - 3000'
Thursday Night Snow Level
15000' - 2500'
Friday Snow Level
1000' - 2000'
Snoqualmie Pass Elevation
Wednesday Night Freezing Level
1500' - 3000'
Thursday Freezing Level
1500' - 3500'
Thursday Night Snow Level
2000' - 3000'
Friday Snow Level
1000' - 2000'
Mt. Hood Elevation
Wednesday Night Freezing Level
3000' - 4500'
Thursday Freezing Level
3000' - 5000'
Thursday Night Snow Level
3000' - 4000'
Friday Snow Level
3500' - 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.

Jump to: Weather Forecast I Snow/Freezing Level I Precipitation I Free Winds 5k I Free Winds 9k I Extended Weather

Previous forecast from Mar 9, 2020

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