Issued: 7:29 AM PST Wednesday, February 28, 2018
by Robert Hahn

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

Weather Synopsis for Wednesday & Saturday

A strengthening surface low and upper low will spin off the Queen Charlotte Islands while an attached frontal system moves over the Pacific Northwest. A warm front will lift NE over the forecast area today bringing approximately 5 F of free air warming and a N-S oriented cold front will pass tonight bringing about 8 F of free air cooling. With plenty of cool air parked on the east side of the Cascade crest, easterly flow developing as the frontal system approaches will keep the Cascades cool throughout the storm. The system will bring increasing S and SE crest-level winds which will be within the moderate to strong range most of the day Wednesday, further increasing during the evening hours. Increasing light snow this morning will become moderate by the afternoon, with heavier precipitation rates on the Cascade Volcanoes which are generally favored by southerly flow.

Following the cold frontal passage Wednesday night, winds will decrease drastically and snow will becoming light and sporadic. 

On Thursday, the cold upper low slides south and will spin 300 miles off the Washington coast by Thursday afternoon, bringing bands of light snow over the forecast area. Partly cloudy conditions are expected and the sun is beginning to gain strength, so in spite of the cool temperatures, expect some surface warming.

Thursday night, the cold upper low slides SE into the Oregon coastal waters, bringing further cooling, particularly in the Mt. Hood area.

Weather Forecast

Olympics
Wednesday Clouds thickening and lowering with light snow developing from late morning onward. Modest warming. Increasing moderate to strong winds.
Wednesday Night Stormy during the evening hours with strong winds and light to moderate snow. Snow and wind will decrease after midnight.
Thursday A chance of light snow with partly cloudy conditions otherwise.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Wednesday Increasing light to moderate snow in the Cascade passes with increasing moderate to heavy snow over Cascade volcanoes. Increasing moderate to strong crest-level winds with light to moderate easterly flow in the passes.
Wednesday Night Moderate snow with moderate to strong southerly winds, heaviest Cascade volcanoes, lightest Cascade passes. Light showers lingering after midnight. Moderate east flow through the passes during the evening hours.
Thursday A chance of light snow with partly cloudy conditions otherwise.
East Slopes of the Washington Cascades
Wednesday Increasing light to occasionally moderate snow with increasing moderate to strong crest-level winds.
Wednesday Night Light to moderate snow with strong southerly winds. Light snow showers lingering after midnight with rapidly decreasing winds.
Thursday A chance of light snow with partly cloudy conditions otherwise.
Mt. Hood
Wednesday Increasing light to moderate snow during the morning hours becoming moderate to occasionally heavy in the afternoon with increasing moderate to strong winds.
Wednesday Night Moderate to heavy snow with strong ridge-top winds during the evening hours. Rapidly decreasing winds after midnight with snow showers becoming generally light.
Thursday Light to occasionally moderate bands of snow with sun breaks in between.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Wednesday Morning Snow Level * 2000' 2000' 1500' ' ' 2000' ' 2500'
Wednesday Afternoon Snow Level * 2500' 2000' 1500' ' ' 2000' ' 3000'
Wednesday Night Snow Level * 2500' 2500' 2000' ' ' 2500' ' 1500'
Thursday Morning Snow Level * 2000' 1500' 2000' ' ' 2000' ' 2000'
Thursday Afternoon Snow Level * 2500' 3000' 2500' ' ' 2500' ' 3500'
Hurricane Ridge Elevation
Wednesday Morning Snow Level
2000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
2500'
(Easterly Flow *)
Wednesday Night Snow Level
2500'
(Easterly Flow *)
Thursday Morning Snow Level
2000'
(Easterly Flow *)
Thursday Afternoon Snow Level
2500'
(Easterly Flow *)
Thursday Night Snow Level
2000'
(Easterly Flow *)
Mt. Baker Elevation
Wednesday Morning Snow Level
2000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
2000'
(Easterly Flow *)
Wednesday Night Snow Level
2500'
(Easterly Flow *)
Thursday Morning Snow Level
1500'
(Easterly Flow *)
Thursday Afternoon Snow Level
3000'
(Easterly Flow *)
Thursday Night Snow Level
2500'
(Easterly Flow *)
Washington Pass Elevation
Wednesday Morning Snow Level
1500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
1500'
(Easterly Flow *)
Wednesday Night Snow Level
2000'
(Easterly Flow *)
Thursday Morning Snow Level
2000'
(Easterly Flow *)
Thursday Afternoon Snow Level
2500'
(Easterly Flow *)
Thursday Night Snow Level
2000'
(Easterly Flow *)
Leavenworth Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
(Easterly Flow *)
Stevens Pass Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
(Easterly Flow *)
Snoqualmie Pass Elevation
Wednesday Morning Snow Level
2000'
(Easterly Flow *)
Wednesday Afternoon Snow Level
2000'
(Easterly Flow *)
Wednesday Night Snow Level
2500'
(Easterly Flow *)
Thursday Morning Snow Level
2000'
(Easterly Flow *)
Thursday Afternoon Snow Level
2500'
(Easterly Flow *)
Thursday Night Snow Level
2000'
(Easterly Flow *)
Mt. Rainier & Crystal Elevation
Wednesday Morning Snow Level
'
(Easterly Flow *)
Wednesday Afternoon Snow Level
'
(Easterly Flow *)
Wednesday Night Snow Level
'
(Easterly Flow *)
Thursday Morning Snow Level
'
(Easterly Flow *)
Thursday Afternoon Snow Level
'
(Easterly Flow *)
Thursday Night Snow Level
'
(Easterly Flow *)
Mt. Hood Elevation
Wednesday Morning Snow Level
2500'
(Easterly Flow *)
Wednesday Afternoon Snow Level
3000'
(Easterly Flow *)
Wednesday Night Snow Level
1500'
(Easterly Flow *)
Thursday Morning Snow Level
2000'
(Easterly Flow *)
Thursday Afternoon Snow Level
3500'
(Easterly Flow *)
Thursday Night Snow Level
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.

Precipitation Forecast

Saturday Saturday
Hurricane Ridge 0 - 0.50 LT 0.25
Mt Baker Ski Area 1.00 - 1.50 LT 0.25
Washington Pass 0.25 - 0.50 LT 0.25
Stevens Pass 0.25 - 0.50 LT 0.25
Snoqualmie Pass 0 - 0.50 LT 0.25
Mission Ridge 0.50 - 0.75 LT 0.10
Crystal Mt 0 - 1.00 LT 0.25
Paradise 1.00 - 1.50 0.25 - 0.50
White Pass 0.25 - 0.50 LT 0.25
Mt Hood Meadows 0.75 - 1.00 LT 0.25
0 - 1.00 LT 0.25

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Wednesday Morning SSE 20 - 30 SSE 15 - 25 SE 15 - 25 --- - S 20 - 30
Wednesday Afternoon S 30 - 40 SE 30 - 40 SE 25 - 35 --- - S 30 - 40
Wednesday Night SSE 20 - 30 ESE 30 - 40 ESE 30 - 40 --- - S 40 - 60
Thursday Morning VAR 0 - 10 S 0 - 10 SSE 0 - 10 --- - SW 10 - 20
Thursday Afternoon E 5 - 15 VAR 0 - 10 ESE 0 - 10 --- - ESE 5 - 15
Hurricane Ridge Elevation
Wednesday Morning SSE 20 - 30
Wednesday Afternoon S 30 - 40
Wednesday Night SSE 20 - 30
Thursday Morning VAR 0 - 10
Thursday Afternoon E 5 - 15
Thursday Night E 5 - 15
Mt. Baker Elevation
Wednesday Morning SSE 15 - 25
Wednesday Afternoon SE 30 - 40
Wednesday Night ESE 30 - 40
Thursday Morning S 0 - 10
Thursday Afternoon VAR 0 - 10
Thursday Night E 5 - 15
Stevens and Snoqualmie Pass Elevation
Wednesday Morning SE 15 - 25
Wednesday Afternoon SE 25 - 35
Wednesday Night ESE 30 - 40
Thursday Morning SSE 0 - 10
Thursday Afternoon ESE 0 - 10
Thursday Night VAR 0 - 10
Mt. Rainier Elevation
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Elevation
Wednesday Morning S 20 - 30
Wednesday Afternoon S 30 - 40
Wednesday Night S 40 - 60
Thursday Morning SW 10 - 20
Thursday Afternoon ESE 5 - 15
Thursday Night WSW 15 - 25
Hurricane Ridge Direction - Speed
Wednesday Morning SSE 20 - 30
Wednesday Afternoon S 30 - 40
Wednesday Night SSE 20 - 30
Thursday Morning VAR 0 - 10
Thursday Afternoon E 5 - 15
Thursday Night E 5 - 15
Mt. Baker Direction - Speed
Wednesday Morning SSE 15 - 25
Wednesday Afternoon SE 30 - 40
Wednesday Night ESE 30 - 40
Thursday Morning S 0 - 10
Thursday Afternoon VAR 0 - 10
Thursday Night E 5 - 15
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning SE 15 - 25
Wednesday Afternoon SE 25 - 35
Wednesday Night ESE 30 - 40
Thursday Morning SSE 0 - 10
Thursday Afternoon ESE 0 - 10
Thursday Night VAR 0 - 10
Mt. Rainier Direction - Speed
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning S 20 - 30
Wednesday Afternoon S 30 - 40
Wednesday Night S 40 - 60
Thursday Morning SW 10 - 20
Thursday Afternoon ESE 5 - 15
Thursday Night WSW 15 - 25

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
Wednesday Morning S 15 - 25 SSE 10 - 20 SW 25 - 35 --- - SW 25 - 35
Wednesday Afternoon SSW 40 - 60 SW 25 - 35 SW 35 - 50 --- - SW 35 - 50
Wednesday Night S 40 - 60 S 35 - 50 SSE 45 - 65 --- - SW 55 - 75
Thursday Morning S 30 - 40 SSE 25 - 35 S 30 - 40 --- - SSW 45 - 65
Thursday Afternoon SE 20 - 30 SE 10 - 20 SSE 10 - 20 --- - SSW 25 - 35
Mt. Baker Direction - Speed
Wednesday Morning S 15 - 25
Wednesday Afternoon SSW 40 - 60
Wednesday Night S 40 - 60
Thursday Morning S 30 - 40
Thursday Afternoon SE 20 - 30
Thursday Night E 0 - 10
Washington Pass Direction - Speed
Wednesday Morning SSE 10 - 20
Wednesday Afternoon SW 25 - 35
Wednesday Night S 35 - 50
Thursday Morning SSE 25 - 35
Thursday Afternoon SE 10 - 20
Thursday Night ESE 0 - 10
Stevens and Snoqualmie Pass Direction - Speed
Wednesday Morning SW 25 - 35
Wednesday Afternoon SW 35 - 50
Wednesday Night SSE 45 - 65
Thursday Morning S 30 - 40
Thursday Afternoon SSE 10 - 20
Thursday Night SSE 0 - 10
Mt. Rainier Direction - Speed
Wednesday Morning --- -
Wednesday Afternoon --- -
Wednesday Night --- -
Thursday Morning --- -
Thursday Afternoon --- -
Thursday Night --- -
Mt. Hood Direction - Speed
Wednesday Morning SW 25 - 35
Wednesday Afternoon SW 35 - 50
Wednesday Night SW 55 - 75
Thursday Morning SSW 45 - 65
Thursday Afternoon SSW 25 - 35
Thursday Night 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.

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

Previous forecast from Feb 27, 2018

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