Issued: 1:57 PM PDT Sunday, March 22, 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 Sunday night through Sunday

An upper low dropping south along the B.C. coast has spread increasing high clouds over the majority of the forecast area this afternoon, leaving sunny skies only for the south Washington Cascades and Mt. Hood. 

A front rotating out from the low will pass through the Cascades late Monday morning. Precipitation will begin over the Olympics and Mt. Baker area near or after midnight but precipitation will take its sweet time spreading further south and inland on Monday morning. As the front washes out over the Cascades mid-day Monday, convective showers will increase in the afternoon with a cold and unstable air mass over the region. Snow levels will fall to 2000-3000' Monday. A few inches of snow look likely for areas west of the Cascade crest, Mt. Hood and the Olympics with the exception of the Mt. Baker area, where 8-12" could fall through Monday afternoon. Snowfall amounts should taper quickly along the eastern Cascade slopes. 

Showers will wind down but not end Monday night. The upper low will hang off the Olympic Peninsula on Tuesday as convective shower activity ramps up quickly during the day. The occasional moderate shower will not be limited to the west slopes, widespread showers are expected to develop on the east side of the Cascades as well. There may be a few thunderstorms in the afternoon to accompany the general increase in showers. 

Weather Forecast

Hurricane Ridge
Sunday Night Cloudy with light rain and snow developing around midnight. Cooling trend.
Mt. Baker
Sunday Night Cloudy with light rain and snow developing around midnight. Cooling trend. Strong winds.
Washington Pass and Leavenworth
Sunday Night Becoming cloudy with clouds lowering this evening. Light rain and snow developing late tonight near the Cascade crest. Cooling trend.
Stevens and Snoqualmie Pass
Sunday Night Becoming cloudy with clouds lowering this evening. Light rain and snow developing late tonight. Cooling trend. Light west wind at Pass level.
Mt. Rainier, Crystal and White Pass
Sunday Night Becoming cloudy with clouds lowering after midnight. Slight chance of light rain or snow before daybreak. Cooling trend.
Mt. Hood
Sunday Night Partly cloudy in the evening, becoming mostly cloudy with increasing low clouds after midnight. .

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Sunday Evening Freezing Level 4500' 5000' 5500' 6500' 5000' 5500' 6500' 8000'
Sunday Night Snow Level 3000' 3000' 3500' 4500' 3500' 3500' 4000' 4500'
Monday Morning Snow Level 2000' 2000' 2500' 3000' 2500' 2500' 2500' 3000'
Monday Afternoon Snow Level 2500' 2500' 3500' 4000' 2500' 2500' 3000' 3000'
Monday Evening Snow Level 2000' 2000' 2000' 2000' 2000' 2000' 2000' 2000'
Monday Night Snow Level 1500' 1000' 1000' 1000' 1000' 1000' 1000' 1500'
Tuesday Morning Snow Level 2000' 2000' 2000' 2000' 2000' 2000' 2000' 2000'
Hurricane Ridge Elevation
Sunday Evening Freezing Level
4500'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
2500'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1500'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'
Mt. Baker Elevation
Sunday Evening Freezing Level
5000'
Sunday Night Snow Level
3000'
Monday Morning Snow Level
2000'
Monday Afternoon Snow Level
2500'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'
Washington Pass Elevation
Sunday Evening Freezing Level
5500'
Sunday Night Snow Level
3500'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
3500'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'
Leavenworth Elevation
Sunday Evening Freezing Level
6500'
Sunday Night Snow Level
4500'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
4000'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
3000'
Stevens Pass Elevation
Sunday Evening Freezing Level
5000'
Sunday Night Snow Level
3500'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2500'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'
Snoqualmie Pass Elevation
Sunday Evening Freezing Level
5500'
Sunday Night Snow Level
3500'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
2500'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'
Mt. Rainier & Crystal Elevation
Sunday Evening Freezing Level
6500'
Sunday Night Snow Level
4000'
Monday Morning Snow Level
2500'
Monday Afternoon Snow Level
3000'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'
Mt. Hood Elevation
Sunday Evening Freezing Level
8000'
Sunday Night Snow Level
4500'
Monday Morning Snow Level
3000'
Monday Afternoon Snow Level
3000'
Monday Evening Snow Level
2000'
Monday Night Snow Level
1500'
Tuesday Morning Snow Level
2000'
Tuesday Afternoon Snow Level
2500'

* 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

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

Free Winds at 5000' (mph)

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

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
Sunday Evening SW 30 - 40 SW 30 - 40 SW 30 - 40 SW 30 - 40 SW 20 - 30
Sunday Night SW 30 - 40 SW 30 - 40 SW 35 - 45 SW 30 - 40 SW 35 - 45
Monday Morning SW 15 - 25 SW 15 - 25 W 25 - 35 W 25 - 35 WSW 40 - 50
Mt. Baker Direction - Speed
Sunday Evening SW 30 - 40
Sunday Night SW 30 - 40
Monday Morning SW 15 - 25
Monday Afternoon SW 10 - 20
Washington Pass Direction - Speed
Sunday Evening SW 30 - 40
Sunday Night SW 30 - 40
Monday Morning SW 15 - 25
Monday Afternoon SW 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Sunday Evening SW 30 - 40
Sunday Night SW 35 - 45
Monday Morning W 25 - 35
Monday Afternoon WSW 30 - 40
Mt. Rainier Direction - Speed
Sunday Evening SW 30 - 40
Sunday Night SW 30 - 40
Monday Morning W 25 - 35
Monday Afternoon SW 25 - 35
Mt. Hood Direction - Speed
Sunday Evening SW 20 - 30
Sunday Night SW 35 - 45
Monday Morning WSW 40 - 50
Monday Afternoon SW 40 - 50

Extended Weather Synopsis for Sunday night through Sunday

Showers will once again wind down but not completely end Tuesday night with the loss of daytime heating. The longwave upper level trough will shift slowly inland on Wednesday, with this unstable air mass encompassing much of the inland NW and extending well into California. Even with the trough exiting, we should have one more day of showers driven largely by daytime heating. Showers will be a bit more scattered on Wednesday but snow levels will remain about as cool as Tuesday. Shower activity will be smeared across both sides of the Cascades in the afternoon. Conditions briefly dry out Wednesday night, but the next frontal system upstream in NW flow aloft will waste no time moving into Washington State on Thursday. This system looks like just the beginning of a more active weather pattern.   

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Tuesday Night Snow Level 500' - 1500' 1000' - 2000' 1000' - 2000'
Wednesday Snow Level 2000' - 3000' 2000' - 3000' 2000' - 3000'
Wednesday Night Snow Level 1000' - 2000' 1000' - 2000' 1000' - 2000'
Mt. Baker Elevation
Tuesday Night Snow Level
500' - 1500'
Wednesday Snow Level
2000' - 3000'
Wednesday Night Snow Level
1000' - 2000'
Thursday Snow Level
2000' - 3000'
Snoqualmie Pass Elevation
Tuesday Night Snow Level
1000' - 2000'
Wednesday Snow Level
2000' - 3000'
Wednesday Night Snow Level
1000' - 2000'
Thursday Snow Level
2000' - 3000'
Mt. Hood Elevation
Tuesday Night Snow Level
1000' - 2000'
Wednesday Snow Level
2000' - 3000'
Wednesday Night Snow Level
1000' - 2000'
Thursday Snow Level
2000' - 3000'

* 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 22, 2020

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