Issued: 2:44 PM PST Sunday, February 17, 2019
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 Sunday night through Thursday

A trough sits over the western US with an embedded upper low over SW Alberta spinning minor amounts of moisture into eastern Washington Sunday afternoon with a ridge a pronounced ridge extending up into SE Alaska leaving our region under a mostly dry northerly flow. This northerly flow combined with the upper low will provide the forcing for a brief surge of modified arctic air to move southward, east of the Cascade Crest and will linger. The Cascades and Olympics can expect decreasing cloud cover as the broad trough shifts SE and an upper-level ridge noses SE into our region late Sunday night into Monday. 

The ridge and dry northerly flow with cool and quiescent conditions should continue through Monday night.

On Tuesday, the next system will spread into the region on a cool NW flow, bringing increasing light precipitation.

Below normal temperatures continue throughout the forecast period.

Weather Forecast

Hurricane Ridge
Sunday Night Mostly clear skies, light winds and cool.
Mt. Baker
Sunday Night Mostly clear skies, light winds and cool.
Washington Pass and Leavenworth
Sunday Night Becoming mostly clearing with low clouds lingering from the I-90 corridor southward. Light winds and quite cold.
Stevens and Snoqualmie Pass
Sunday Night Low clouds lingering in many areas. Light to occasional moderate E flow to the pass with light winds at 5000 ft. Cool.
Mt. Rainier, Crystal and White Pass
Sunday Night Low clouds lingering in many areas with clear skies aloft. Cool with light winds.
Mt. Hood
Sunday Night Low clouds with clear skies aloft. Light to occasional moderate winds. Cool.

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 2500' 2000' 1500' 2500' 2500' 2000' 2000' 2000'
Sunday Night Freezing Level * 1500' 500' 500' 1000' 1000' 1000' 1000' 1000'
Monday Morning Freezing Level * 1000' 500' 500' 500' 500' 1000' 500' 500'
Monday Afternoon Freezing Level 2000' 1000' 1500' 1500' 2000' 2000' 2500' 2000'
Monday Evening Snow Level 1500' 1000' 500' 500' 1000' 1000' 1500' 1500'
Monday Night Snow Level 500' 0' 0' 0' 0' 0' 0' 1000'
Tuesday Morning Snow Level 500' 0' 0' 0' 0' 0' 0' 500'
Hurricane Ridge Elevation
Sunday Evening Freezing Level
2500'
Sunday Night Freezing Level
1500'
(Easterly Flow *)
Monday Morning Freezing Level
1000'
(Easterly Flow *)
Monday Afternoon Freezing Level
2000'
Monday Evening Snow Level
1500'
Monday Night Snow Level
500'
Tuesday Morning Snow Level
500'
Tuesday Afternoon Snow Level
1500'
Mt. Baker Elevation
Sunday Evening Freezing Level
2000'
Sunday Night Freezing Level
500'
(Easterly Flow *)
Monday Morning Freezing Level
500'
(Easterly Flow *)
Monday Afternoon Freezing Level
1000'
Monday Evening Snow Level
1000'
Monday Night Snow Level
0'
Tuesday Morning Snow Level
0'
Tuesday Afternoon Snow Level
1000'
Washington Pass Elevation
Sunday Evening Freezing Level
1500'
Sunday Night Freezing Level
500'
(Easterly Flow *)
Monday Morning Freezing Level
500'
(Easterly Flow *)
Monday Afternoon Freezing Level
1500'
Monday Evening Snow Level
500'
Monday Night Snow Level
0'
Tuesday Morning Snow Level
0'
Tuesday Afternoon Snow Level
1000'
Leavenworth Elevation
Sunday Evening Freezing Level
2500'
Sunday Night Freezing Level
1000'
(Easterly Flow *)
Monday Morning Freezing Level
500'
(Easterly Flow *)
Monday Afternoon Freezing Level
1500'
Monday Evening Snow Level
500'
Monday Night Snow Level
0'
Tuesday Morning Snow Level
0'
Tuesday Afternoon Snow Level
1000'
Stevens Pass Elevation
Sunday Evening Freezing Level
2500'
Sunday Night Freezing Level
1000'
(Easterly Flow *)
Monday Morning Freezing Level
500'
(Easterly Flow *)
Monday Afternoon Freezing Level
2000'
Monday Evening Snow Level
1000'
Monday Night Snow Level
0'
Tuesday Morning Snow Level
0'
Tuesday Afternoon Snow Level
1000'
Snoqualmie Pass Elevation
Sunday Evening Freezing Level
2000'
Sunday Night Freezing Level
1000'
(Easterly Flow *)
Monday Morning Freezing Level
1000'
(Easterly Flow *)
Monday Afternoon Freezing Level
2000'
Monday Evening Snow Level
1000'
Monday Night Snow Level
0'
Tuesday Morning Snow Level
0'
Tuesday Afternoon Snow Level
1000'
Mt. Rainier & Crystal Elevation
Sunday Evening Freezing Level
2000'
Sunday Night Freezing Level
1000'
(Easterly Flow *)
Monday Morning Freezing Level
500'
(Easterly Flow *)
Monday Afternoon Freezing Level
2500'
Monday Evening Snow Level
1500'
Monday Night Snow Level
0'
Tuesday Morning Snow Level
0'
Tuesday Afternoon Snow Level
1500'
Mt. Hood Elevation
Sunday Evening Freezing Level
2000'
Sunday Night Freezing Level
1000'
(Easterly Flow *)
Monday Morning Freezing Level
500'
(Easterly Flow *)
Monday Afternoon Freezing Level
2000'
Monday Evening Snow Level
1500'
Monday Night Snow Level
1000'
Tuesday Morning Snow Level
500'
Tuesday Afternoon Snow Level
1500'

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

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Sunday Evening NW 5 - 15 NE 5 - 15 WNW 5 - 15 WNW 5 - 15 W 5 - 15
Sunday Night NNW 5 - 15 ENE 0 - 10 W 5 - 15 WNW 5 - 15 W 10 - 20
Monday Morning VAR 0 - 10 VAR 0 - 10 W 0 - 10 W 5 - 15 W 5 - 15
Hurricane Ridge Elevation
Sunday Evening NW 5 - 15
Sunday Night NNW 5 - 15
Monday Morning VAR 0 - 10
Monday Afternoon WSW 5 - 15
Mt. Baker Elevation
Sunday Evening NE 5 - 15
Sunday Night ENE 0 - 10
Monday Morning VAR 0 - 10
Monday Afternoon WSW 5 - 15
Stevens and Snoqualmie Pass Elevation
Sunday Evening WNW 5 - 15
Sunday Night W 5 - 15
Monday Morning W 0 - 10
Monday Afternoon WSW 5 - 15
Mt. Rainier Elevation
Sunday Evening WNW 5 - 15
Sunday Night WNW 5 - 15
Monday Morning W 5 - 15
Monday Afternoon W 5 - 15
Mt. Hood Elevation
Sunday Evening W 5 - 15
Sunday Night W 10 - 20
Monday Morning W 5 - 15
Monday Afternoon W 10 - 20
Hurricane Ridge Direction - Speed
Sunday Evening NW 5 - 15
Sunday Night NNW 5 - 15
Monday Morning VAR 0 - 10
Monday Afternoon WSW 5 - 15
Mt. Baker Direction - Speed
Sunday Evening NE 5 - 15
Sunday Night ENE 0 - 10
Monday Morning VAR 0 - 10
Monday Afternoon WSW 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Sunday Evening WNW 5 - 15
Sunday Night W 5 - 15
Monday Morning W 0 - 10
Monday Afternoon WSW 5 - 15
Mt. Rainier Direction - Speed
Sunday Evening WNW 5 - 15
Sunday Night WNW 5 - 15
Monday Morning W 5 - 15
Monday Afternoon W 5 - 15
Mt. Hood Direction - Speed
Sunday Evening W 5 - 15
Sunday Night W 10 - 20
Monday Morning W 5 - 15
Monday 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
Sunday Evening NNW 5 - 15 NNW 10 - 20 NNW 15 - 25 NNW 20 - 30 N 15 - 25
Sunday Night N 10 - 20 NW 10 - 20 NW 10 - 20 NW 15 - 25 NNW 20 - 30
Monday Morning NNW 15 - 25 NNW 15 - 25 NNW 20 - 30 NNW 20 - 30 NNW 15 - 25
Mt. Baker Direction - Speed
Sunday Evening NNW 5 - 15
Sunday Night N 10 - 20
Monday Morning NNW 15 - 25
Monday Afternoon NNW 10 - 20
Washington Pass Direction - Speed
Sunday Evening NNW 10 - 20
Sunday Night NW 10 - 20
Monday Morning NNW 15 - 25
Monday Afternoon NNW 20 - 30
Stevens and Snoqualmie Pass Direction - Speed
Sunday Evening NNW 15 - 25
Sunday Night NW 10 - 20
Monday Morning NNW 20 - 30
Monday Afternoon NNW 20 - 30
Mt. Rainier Direction - Speed
Sunday Evening NNW 20 - 30
Sunday Night NW 15 - 25
Monday Morning NNW 20 - 30
Monday Afternoon NNW 20 - 30
Mt. Hood Direction - Speed
Sunday Evening N 15 - 25
Sunday Night NNW 20 - 30
Monday Morning NNW 15 - 25
Monday Afternoon NNW 20 - 30

Extended Weather Synopsis for Thursday night through Thursday

On Tuesday night, the precipitation is likely to be heaviest as a cool NW post-frontal flow is accompanied by a deep trough. A convergence zone is likely to spread some heavier precipitation into some areas. 

Wednesday, snow shower activity will continue mainly over the southern Cascades and Mt. Hood areas with clearing from north to south through Wednesday night. A ridge of high pressure will nose into the region slightly on Thursday bringing fair weather.

Below normal temperatures continue throughout the forecast period.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Tuesday Night Snow Level 0' - 1000' 500' - 1500' 1500' - 2500'
Wednesday Snow Level 0' - 1000' 0' - 1000' 1000' - 2000'
Wednesday Night Snow Level 0' - 2000' 0' - 2000' 0' - 2000'
Mt. Baker Elevation
Tuesday Night Snow Level
0' - 1000'
Wednesday Snow Level
0' - 1000'
Wednesday Night Snow Level
0' - 2000'
Thursday Freezing Level
0' - 1000'
Snoqualmie Pass Elevation
Tuesday Night Snow Level
500' - 1500'
Wednesday Snow Level
0' - 1000'
Wednesday Night Snow Level
0' - 2000'
Thursday Freezing Level
500' - 2500'
Mt. Hood Elevation
Tuesday Night Snow Level
1500' - 2500'
Wednesday Snow Level
1000' - 2000'
Wednesday Night Snow Level
0' - 2000'
Thursday Freezing Level
0' - 2000'

* 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 Feb 17, 2019

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