Issued: 2:30 PM PST Thursday, January 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 Thursday night through Wednesday

A cold air mass sits over the Pacific Northwest as we enter another very active and wintry stretch of weather.

A strong storm dropping into the region on NW flow should bring increasing and lowering clouds Thursday night with precipitation arriving in some areas before Friday morning. SSW winds should increase significantly from the early morning hours onwards. 

A cold front ahead of the surface low and upper trough spreads increasingly heavy snow and strong SSW winds across the region on Friday with the front approaching the coastline on Friday morning and crossing the Cascades by mid-afternoon. Winds should peak late-morning in the Olympics, and early afternoon for the Cascades. Mt Baker, Snoqualmie, and Paradise should all see 1-1.5" of snow water equivalent with 1-2 ft of snow accumulating by the end of the day Friday. East flow from during the day Friday should keep the Passes quite cold. The system brings subtle warming, but snow levels should stay low throughout the event, peaking around 2000 ft for the Washington Cascades. 

Friday night, the upper low moves over the Cascades, sustaining moderate to heavy snowfall across the region with the most in areas further south where the winds WSW flow circulating around the trough should be strongest and providing the most orographic lift. 

On Saturday, with the upper trough sliding eastward, the region sustains light to moderate snow showers with a brisk WNW flow continuing to focus the heavier snowfall from Snoqualmie Pass southward. Lighter winds should be found in areas further north.

Weather Forecast

Hurricane Ridge
Thursday Night Increasing clouds lowering and thickening with light snow developing in the early morning hours.
Mt. Baker
Thursday Night Cloudy with light snow developing in the early morning hours.
Washington Pass and Leavenworth
Thursday Night Cloudy with light snow developing in the early morning hours.
Stevens and Snoqualmie Pass
Thursday Night Decreasing snow showers in the evening, then becoming cloudy with light snow developing in the early morning hours.
Mt. Rainier, Crystal and White Pass
Thursday Night Decreasing snow showers in the evening, then becoming cloudy with light snow developing in the early morning hours.
Mt. Hood
Thursday Night Decreasing snow showers in the evening, then becoming cloudy with light snow possibly developing in the early morning hours.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Thursday Evening Snow Level 1500' 500' 0' 1000' 0' 500' 1000' 1500'
Thursday Night Snow Level 1000' 500' 0' 500' 0' 0' 500' 1500'
Friday Morning Snow Level * 1500' 500' 0' 500' 500' 500' 500' 1500'
Friday Afternoon Snow Level * 3000' 1000' 500' 1000' 1000' 1000' 2000' 2500'
Friday Evening Snow Level * 3000' 2000' 1000' 1500' 1500' 2000' 2500' 3000'
Friday Night Snow Level 2500' 2000' 1500' 1500' 2000' 2000' 2000' 3000'
Saturday Morning Snow Level 2500' 2000' 1000' 1500' 1500' 2000' 2000' 3000'
Hurricane Ridge Elevation
Thursday Evening Snow Level
1500'
Thursday Night Snow Level
1000'
Friday Morning Snow Level
1500'
(Easterly Flow *)
Friday Afternoon Snow Level
3000'
(Easterly Flow *)
Friday Evening Snow Level
3000'
(Easterly Flow *)
Friday Night Snow Level
2500'
Saturday Morning Snow Level
2500'
Saturday Afternoon Snow Level
2000'
Mt. Baker Elevation
Thursday Evening Snow Level
500'
Thursday Night Snow Level
500'
Friday Morning Snow Level
500'
(Easterly Flow *)
Friday Afternoon Snow Level
1000'
(Easterly Flow *)
Friday Evening Snow Level
2000'
(Easterly Flow *)
Friday Night Snow Level
2000'
Saturday Morning Snow Level
2000'
Saturday Afternoon Snow Level
2000'
Washington Pass Elevation
Thursday Evening Snow Level
0'
Thursday Night Snow Level
0'
Friday Morning Snow Level
0'
(Easterly Flow *)
Friday Afternoon Snow Level
500'
(Easterly Flow *)
Friday Evening Snow Level
1000'
(Easterly Flow *)
Friday Night Snow Level
1500'
Saturday Morning Snow Level
1000'
Saturday Afternoon Snow Level
2000'
Leavenworth Elevation
Thursday Evening Snow Level
1000'
Thursday Night Snow Level
500'
Friday Morning Snow Level
500'
(Easterly Flow *)
Friday Afternoon Snow Level
1000'
(Easterly Flow *)
Friday Evening Snow Level
1500'
(Easterly Flow *)
Friday Night Snow Level
1500'
Saturday Morning Snow Level
1500'
Saturday Afternoon Snow Level
2500'
Stevens Pass Elevation
Thursday Evening Snow Level
0'
Thursday Night Snow Level
0'
Friday Morning Snow Level
500'
(Easterly Flow *)
Friday Afternoon Snow Level
1000'
(Easterly Flow *)
Friday Evening Snow Level
1500'
(Easterly Flow *)
Friday Night Snow Level
2000'
Saturday Morning Snow Level
1500'
Saturday Afternoon Snow Level
2500'
Snoqualmie Pass Elevation
Thursday Evening Snow Level
500'
Thursday Night Snow Level
0'
Friday Morning Snow Level
500'
(Easterly Flow *)
Friday Afternoon Snow Level
1000'
(Easterly Flow *)
Friday Evening Snow Level
2000'
(Easterly Flow *)
Friday Night Snow Level
2000'
Saturday Morning Snow Level
2000'
Saturday Afternoon Snow Level
2500'
Mt. Rainier & Crystal Elevation
Thursday Evening Snow Level
1000'
Thursday Night Snow Level
500'
Friday Morning Snow Level
500'
(Easterly Flow *)
Friday Afternoon Snow Level
2000'
(Easterly Flow *)
Friday Evening Snow Level
2500'
(Easterly Flow *)
Friday Night Snow Level
2000'
Saturday Morning Snow Level
2000'
Saturday Afternoon Snow Level
2500'
Mt. Hood Elevation
Thursday Evening Snow Level
1500'
Thursday Night Snow Level
1500'
Friday Morning Snow Level
1500'
(Easterly Flow *)
Friday Afternoon Snow Level
2500'
(Easterly Flow *)
Friday Evening Snow Level
3000'
(Easterly Flow *)
Friday Night Snow Level
3000'
Saturday Morning Snow Level
3000'
Saturday 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

Thursday Night Wednesday Wednesday Night Wednesday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge LT 0.10 0.50 0.25 - 0.50 LT 0.25
Mt Baker Ski Area LT 0.25 1.50 0.25 - 0.50 0.25
Washington Pass 0 0.50 - 0.75 0.25 LT 0.25
Leavenworth 0 0.25 - 0.50 LT 0.25 LT 0.10
Stevens Pass LT 0.10 0.75 -1.00 0.50 0.25
Snoqualmie Pass LT 0.10 1.00 - 1.50 0.75 -1.00 0.50
Mission Ridge 0 0.25 LT 0.10 LT 0.10
Crystal Mt LT 0.10 0.50 0.25 0.25 - 0.50
Paradise LT 0.10 1.50 1.00 - 1.50 0.50 - 0.75
White Pass 0 0.50 - 0.75 0.50 - 0.75 0.25
Mt Hood Meadows LT 0.10 0.75 1.50 0.75 -1.00
LT 0.10 0.75 1.50 1.00
Hurricane Ridge Precipitation Forecast
Thursday Night LT 0.10
Wednesday 0.50
Wednesday Night 0.25 - 0.50
Wednesday LT 0.25
Mt Baker Ski Area Precipitation Forecast
Thursday Night LT 0.25
Wednesday 1.50
Wednesday Night 0.25 - 0.50
Wednesday 0.25
Washington Pass Precipitation Forecast
Thursday Night 0
Wednesday 0.50 - 0.75
Wednesday Night 0.25
Wednesday LT 0.25
Leavenworth Precipitation Forecast
Thursday Night 0
Wednesday 0.25 - 0.50
Wednesday Night LT 0.25
Wednesday LT 0.10
Stevens Pass Precipitation Forecast
Thursday Night LT 0.10
Wednesday 0.75 -1.00
Wednesday Night 0.50
Wednesday 0.25
Snoqualmie Pass Precipitation Forecast
Thursday Night LT 0.10
Wednesday 1.00 - 1.50
Wednesday Night 0.75 -1.00
Wednesday 0.50
Mission Ridge Precipitation Forecast
Thursday Night 0
Wednesday 0.25
Wednesday Night LT 0.10
Wednesday LT 0.10
Crystal Mt Precipitation Forecast
Thursday Night LT 0.10
Wednesday 0.50
Wednesday Night 0.25
Wednesday 0.25 - 0.50
Paradise Precipitation Forecast
Thursday Night LT 0.10
Wednesday 1.50
Wednesday Night 1.00 - 1.50
Wednesday 0.50 - 0.75
White Pass Precipitation Forecast
Thursday Night 0
Wednesday 0.50 - 0.75
Wednesday Night 0.50 - 0.75
Wednesday 0.25
Mt Hood Meadows Precipitation Forecast
Thursday Night LT 0.10
Wednesday 0.75
Wednesday Night 1.50
Wednesday 0.75 -1.00
Timberline Precipitation Forecast
Thursday Night LT 0.10
Wednesday 0.75
Wednesday Night 1.50
Wednesday 1.00

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Thursday Evening WSW 5 - 15 SSW 5 - 15 WNW 5 - 15 WSW 5 - 15 WNW 15 - 25
Thursday Night S 15 - 25 S 15 - 25 SW 5 - 15 SW 5 - 15 W 15 - 25
Friday Morning SSW 25 - 35 SSE 25 - 35 SSW 10 - 20 SSW 10 - 20 SW 15 - 25
Hurricane Ridge Elevation
Thursday Evening WSW 5 - 15
Thursday Night S 15 - 25
Friday Morning SSW 25 - 35
Friday Afternoon WSW 15 - 25
Mt. Baker Elevation
Thursday Evening SSW 5 - 15
Thursday Night S 15 - 25
Friday Morning SSE 25 - 35
Friday Afternoon S 20 - 30
Stevens and Snoqualmie Pass Elevation
Thursday Evening WNW 5 - 15
Thursday Night SW 5 - 15
Friday Morning SSW 10 - 20
Friday Afternoon SSW 15 - 25
Mt. Rainier Elevation
Thursday Evening WSW 5 - 15
Thursday Night SW 5 - 15
Friday Morning SSW 10 - 20
Friday Afternoon SSW 15 - 25
Mt. Hood Elevation
Thursday Evening WNW 15 - 25
Thursday Night W 15 - 25
Friday Morning SW 15 - 25
Friday Afternoon SW 20 - 30
Hurricane Ridge Direction - Speed
Thursday Evening WSW 5 - 15
Thursday Night S 15 - 25
Friday Morning SSW 25 - 35
Friday Afternoon WSW 15 - 25
Mt. Baker Direction - Speed
Thursday Evening SSW 5 - 15
Thursday Night S 15 - 25
Friday Morning SSE 25 - 35
Friday Afternoon S 20 - 30
Stevens and Snoqualmie Pass Direction - Speed
Thursday Evening WNW 5 - 15
Thursday Night SW 5 - 15
Friday Morning SSW 10 - 20
Friday Afternoon SSW 15 - 25
Mt. Rainier Direction - Speed
Thursday Evening WSW 5 - 15
Thursday Night SW 5 - 15
Friday Morning SSW 10 - 20
Friday Afternoon SSW 15 - 25
Mt. Hood Direction - Speed
Thursday Evening WNW 15 - 25
Thursday Night W 15 - 25
Friday Morning SW 15 - 25
Friday Afternoon SW 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
Thursday Evening W 20 - 30 W 10 - 20 WNW 25 - 35 WNW 25 - 35 NW 25 - 35
Thursday Night WSW 20 - 30 W 15 - 25 W 35 - 45 W 30 - 40 WNW 40 - 50
Friday Morning WSW 45 - 60 SW 35 - 45 WSW 40 - 55 W 40 - 55 W 40 - 55
Mt. Baker Direction - Speed
Thursday Evening W 20 - 30
Thursday Night WSW 20 - 30
Friday Morning WSW 45 - 60
Friday Afternoon WSW 45 - 60
Washington Pass Direction - Speed
Thursday Evening W 10 - 20
Thursday Night W 15 - 25
Friday Morning SW 35 - 45
Friday Afternoon WSW 40 - 50
Stevens and Snoqualmie Pass Direction - Speed
Thursday Evening WNW 25 - 35
Thursday Night W 35 - 45
Friday Morning WSW 40 - 55
Friday Afternoon WSW 55 - 75
Mt. Rainier Direction - Speed
Thursday Evening WNW 25 - 35
Thursday Night W 30 - 40
Friday Morning W 40 - 55
Friday Afternoon WSW 55 - 75
Mt. Hood Direction - Speed
Thursday Evening NW 25 - 35
Thursday Night WNW 40 - 50
Friday Morning W 40 - 55
Friday Afternoon WSW 45 - 65

Extended Weather Synopsis for Wednesday night through Wednesday

The wintry weather continues into the extended forecast. A weaker disturbance sliding down the coast of British Columbia Saturday night as light to moderate snow shower activity continues in the same general areas. The disturbance should bring increased snowfall to the region on Sunday as it moves onshore over Washington by the afternoon. This could result in heavier snowfall extending back northward toward the North Cascades. Meanwhile, a surface boundary-pushing south along the BC-US border knocks at the door and pushes southward across the region Sunday night and Monday. This could focus a band of convergence as a surface front slowly pushes south. The heaviest precipitation should push southward once again where the moist air continues to stream in on a NW flow. We'll be measuring snowfall in feet, not inches in the southern part of the forecast area with this sustained event.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Saturday Night Snow Level 0' - 1000' 500' - 1500' 1000' - 2000'
Sunday Snow Level 500' - 1500' 1000' - 2000' 2000' - 3000'
Sunday Night Snow Level 0' - 0' 0' - 1000' 1000' - 2000'
Mt. Baker Elevation
Saturday Night Snow Level
0' - 1000'
Sunday Snow Level
500' - 1500'
Sunday Night Snow Level
0' - 0'
Monday Snow Level
0' - 0'
(Easterly Flow *)
Snoqualmie Pass Elevation
Saturday Night Snow Level
500' - 1500'
Sunday Snow Level
1000' - 2000'
Sunday Night Snow Level
0' - 1000'
Monday Snow Level
0' - 0'
(Easterly Flow *)
Mt. Hood Elevation
Saturday Night Snow Level
1000' - 2000'
Sunday Snow Level
2000' - 3000'
Sunday Night Snow Level
1000' - 2000'
Monday Snow Level
0' - 1000'
(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 Jan 9, 2020

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