Issued: 7:16 AM PST Tuesday, February 21, 2017
by Dennis D'Amico

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

Weather Synopsis for Tuesday & Friday

A weak low pressure system will traverse across northern Oregon and into southeast Washington today. This track is similar to Monday's low pressure system, but with the precipitation shield a bit further south. Light precipitation will mainly affect the Mt. Hood region through mid-day with periods of light snow reaching northward into the central Washington Cascades. As the low passes east of the Cascades, an upper level trough will begin to move over the Pacific Northwest with a cooling trend taking place in the afternoon. Sunbreaks are possible in the afternoon. 

Afternoon shower activity should be fairly light but a possible convergence zone between Snoqualmie and Stevens Pass may produce bands of moderate showers through the evening. Showers should taper down overnight.

A weak upper level low coming down in the northerly branch of the jet stream will help dig a cold upper level trough over the area on Wednesday. The air mass will be slightly unstable with a chance for a few heavier showers potentially containing graupel in the afternoon. It looks fairly cloudy for the Olympics and west slopes on Wednesday but the east slopes may enjoy more sunbreaks before the convective clouds begin to fill in during the afternoon. Showers should again taper down overnight. 

Weather Forecast

Washington Cascades near and west of the crest including Stevens, Snoqualmie, and White Passes
Tuesday Morning

Periods of light rain and snow mainly south and central Cascades. Cloudy north Cascades. 

Tuesday Afternoon - Tuesday Evening

Mostly cloudy with light scattered rain and snow showers, occasionally moderate near a potential convergence zone between Stevens and Snoqualmie Passes. A few afternoon sunbreaks. Slight cooling trend. 

Tuesday Night - Wednesday Morning

Mostly cloudy with isolated snow showers. Colder. 

Wednesday Afternoon

Mostly cloudy with scattered light to occasionally moderate snow showers. 

Olympics
Tuesday - Tuesday Evening

Mostly cloudy with light scattered rain and snow showers. A few afternoon sunbreaks. Slight cooling trend. 

Tuesday Night - Wednesday Morning

Mostly cloudy with isolated snow showers. Colder. 

Wednesday Afternoon

Cloudy with scattered light to moderate snow showers. 

East slopes of the Washington Cascades
Tuesday Morning

Periods of light rain and snow mainly southeast and central-east Cascades. Mostly cloudy northeast Cascades. 

Tuesday Afternoon - Tuesday Evening

Mostly cloudy with light scattered rain and snow showers. A few afternoon sunbreaks. 

Tuesday Night - Wednesday Morning

Partly to mostly cloudy with isolated snow showers. Turning colder.  

Wednesday Afternoon

Mostly cloudy with scattered light snow showers.  

Mt. Hood Area
Tuesday Morning - Tuesday Mid-day

Light rain and snow. 

Tuesday Afternoon - Tuesday Evening

Mostly cloudy with light scattered rain and snow showers. A few afternoon sunbreaks. Slight cooling trend. 

Tuesday Night - Wednesday Morning

Mostly cloudy with isolated snow showers. Colder. 

Wednesday Afternoon

Mostly cloudy with scattered light to occasionally moderate snow showers. 

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Tuesday Morning - Tuesday Mid-day Snow Level 2500' 2500' 2500' ' ' 2500' ' 3500'
Tuesday Afternoon Snow Level 2000' 2000' 3500' ' ' 2000' ' 2500'
Tuesday Night - Wednesday Morning Snow Level 1000' 1000' 500' ' ' 1000' ' 1500'
Wednesday Afternoon Snow Level 1500' 1500' 1500' ' ' 1500' ' 1500'
Hurricane Ridge Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
2500'
Tuesday Afternoon Snow Level
2000'
Tuesday Night - Wednesday Morning Snow Level
1000'
Wednesday Afternoon Snow Level
1500'
Wednesday Night Snow Level
0'
Mt. Baker Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
2500'
Tuesday Afternoon Snow Level
2000'
Tuesday Night - Wednesday Morning Snow Level
1000'
Wednesday Afternoon Snow Level
1500'
Wednesday Night Snow Level
0'
Washington Pass Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
2500'
Tuesday Afternoon Snow Level
3500'
Tuesday Night - Wednesday Morning Snow Level
500'
Wednesday Afternoon Snow Level
1500'
Wednesday Night Snow Level
0'
Leavenworth Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
'
Tuesday Afternoon Snow Level
'
Tuesday Night - Wednesday Morning Snow Level
'
Wednesday Afternoon Snow Level
'
Wednesday Night Snow Level
'
Stevens Pass Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
'
Tuesday Afternoon Snow Level
'
Tuesday Night - Wednesday Morning Snow Level
'
Wednesday Afternoon Snow Level
'
Wednesday Night Snow Level
'
Snoqualmie Pass Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
2500'
Tuesday Afternoon Snow Level
2000'
Tuesday Night - Wednesday Morning Snow Level
1000'
Wednesday Afternoon Snow Level
1500'
Wednesday Night Snow Level
0'
Mt. Rainier & Crystal Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
'
Tuesday Afternoon Snow Level
'
Tuesday Night - Wednesday Morning Snow Level
'
Wednesday Afternoon Snow Level
'
Wednesday Night Snow Level
'
Mt. Hood Elevation
Tuesday Morning - Tuesday Mid-day Snow Level
3500'
Tuesday Afternoon Snow Level
2500'
Tuesday Night - Wednesday Morning Snow Level
1500'
Wednesday Afternoon Snow Level
1500'
Wednesday Night Snow Level
500'

* 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

Friday Friday
Hurricane Ridge LT 0.25 LT 0.25
Mt Baker Ski Area LT 0.25 LT 0.25
Washington Pass LT 0.10 LT 0.10
Stevens Pass LT 0.25 LT 0.25
Snoqualmie Pass LT 0.25 LT 0.25
Mission Ridge LT 0.25 LT 0.10
Crystal Mt LT 0.25 LT 0.25
Paradise 0.25 - 0.50 LT 0.25
White Pass LT 0.25 LT 0.10
Mt Hood Meadows 0 - 0.50 LT 0.25
0 - 0.50 LT 0.25

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Tuesday Morning S 0 - 10 VAR 0 - 10 E 0 - 10 --- - E 0 - 10
Tuesday Afternoon W 10 - 20 SW 0 - 10 WNW 5 - 15 --- - WNW 15 - 25
Tuesday Night W 10 - 20 SW 5 - 15 WSW 15 - 25 --- - W 15 - 25
Wednesday W 5 - 15 SW 0 - 10 WSW 5 - 15 --- - W 5 - 15
Hurricane Ridge Elevation
Tuesday Morning S 0 - 10
Tuesday Afternoon W 10 - 20
Tuesday Night W 10 - 20
Wednesday W 5 - 15
Wednesday Night VAR 0 - 10
Mt. Baker Elevation
Tuesday Morning VAR 0 - 10
Tuesday Afternoon SW 0 - 10
Tuesday Night SW 5 - 15
Wednesday SW 0 - 10
Wednesday Night VAR 0 - 10
Stevens and Snoqualmie Pass Elevation
Tuesday Morning E 0 - 10
Tuesday Afternoon WNW 5 - 15
Tuesday Night WSW 15 - 25
Wednesday WSW 5 - 15
Wednesday Night W 0 - 10
Mt. Rainier Elevation
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday --- -
Wednesday Night --- -
Mt. Hood Elevation
Tuesday Morning E 0 - 10
Tuesday Afternoon WNW 15 - 25
Tuesday Night W 15 - 25
Wednesday W 5 - 15
Wednesday Night W 0 - 10
Hurricane Ridge Direction - Speed
Tuesday Morning S 0 - 10
Tuesday Afternoon W 10 - 20
Tuesday Night W 10 - 20
Wednesday W 5 - 15
Wednesday Night VAR 0 - 10
Mt. Baker Direction - Speed
Tuesday Morning VAR 0 - 10
Tuesday Afternoon SW 0 - 10
Tuesday Night SW 5 - 15
Wednesday SW 0 - 10
Wednesday Night VAR 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning E 0 - 10
Tuesday Afternoon WNW 5 - 15
Tuesday Night WSW 15 - 25
Wednesday WSW 5 - 15
Wednesday Night W 0 - 10
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night --- -
Wednesday --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning E 0 - 10
Tuesday Afternoon WNW 15 - 25
Tuesday Night W 15 - 25
Wednesday W 5 - 15
Wednesday Night W 0 - 10

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
Tuesday Morning SW 0 - 10 SW 0 - 10 SW 0 - 10 --- - SW 15 - 25
Tuesday Afternoon W 10 - 20 W 10 - 20 W 20 - 30 --- - WNW 25 - 35
Tuesday Night - Wednesday Morning W 15 - 25 W 20 - 35 W 20 - 35 --- - WNW 20 - 30
Wednesday Afternoon W 5 - 15 W 5 - 15 W 10 - 20 --- - W 15 - 25
Mt. Baker Direction - Speed
Tuesday Morning SW 0 - 10
Tuesday Afternoon W 10 - 20
Tuesday Night - Wednesday Morning W 15 - 25
Wednesday Afternoon W 5 - 15
Wednesday Night NW 5 - 15
Washington Pass Direction - Speed
Tuesday Morning SW 0 - 10
Tuesday Afternoon W 10 - 20
Tuesday Night - Wednesday Morning W 20 - 35
Wednesday Afternoon W 5 - 15
Wednesday Night NW 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Tuesday Morning SW 0 - 10
Tuesday Afternoon W 20 - 30
Tuesday Night - Wednesday Morning W 20 - 35
Wednesday Afternoon W 10 - 20
Wednesday Night NW 5 - 15
Mt. Rainier Direction - Speed
Tuesday Morning --- -
Tuesday Afternoon --- -
Tuesday Night - Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Mt. Hood Direction - Speed
Tuesday Morning SW 15 - 25
Tuesday Afternoon WNW 25 - 35
Tuesday Night - Wednesday Morning WNW 20 - 30
Wednesday Afternoon W 15 - 25
Wednesday Night NW 5 - 15

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.

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

Previous forecast from Feb 20, 2017

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