Issued: 7:45 AM PDT Friday, April 6, 2018
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 Friday & Wednesday

Today will be a relative break in our active and wet pattern as the bulk of the moisture from an atmospheric river is directed into Calfornia. Scattered showers this morning will diminish in the afternoon. Weak upper level ridging building over the area today will help trap moisture and clouds below Cascade Crest level, but a few sunbreaks are likely today.

A developing low pressure system offshore, impressive by April standards, will curl north toward Vancouver Island late tonight. The associated front will pass through the region from south to north late tonight through Saturday morning. Precipitation will begin with high snow levels, and slowly lower through the day on Saturday. The flow aloft will become more southerly, and heavier precipitation will favor the Olympics and volcanic peaks, but will also spread moderate precipitation totals over to the east slopes of the Cascades.

A relative lull in the heavier precipitation should occur Saturday afternoon for the Washington Cascades, but heavier and more widespread shower activity will return Saturday night as the low pressure system sends secondary shortwave troughs inland. Snow levels will fall further Saturday night to around 4500 feet across the region. S-SW winds will be strongest for the Olympics and from Snoqualmie Pass area and south to Mt. Hood through the short term period. 

Weather Forecast

Olympics
Friday Cloudy with scattered light rain showers this morning becoming mostly cloudy with a chance of light rain showers this afternoon. A few sunbreaks possible beginning late morning. Mild.
Friday Night Cloudy. Light rain developing after midnight. Mild.
Saturday Stormy with light to moderate rain and snow. Slow cooling trend. Very windy.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Friday Cloudy with scattered light rain showers this morning becoming mostly cloudy with a chance of light rain showers this afternoon. A few sunbreaks possible beginning late morning. Mild.
Friday Night Cloudy. Rain developing south Washington Cascades late Friday night and spreading northward. Mild.
Saturday Stormy in the morning with moderate to locally heavy rain and snow, becoming scattered light to occasionally moderate rain and snow showers from late morning through the afternoon. Slow cooling trend. Becoming very windy, especially south Washington Cascades.
East Slopes of the Washington Cascades
Friday Cloudy with scattered light rain showers this morning becoming mostly cloudy with a chance of light rain showers this afternoon. A few sunbreaks possible beginning late morning. Mild.
Friday Night Cloudy. Rain developing south Washington Cascades late Friday night and spreading northward. Mild.
Saturday Stormy in the morning with moderate to locally heavy rain and snow, becoming scattered light to occasionally moderate rain and snow showers from late morning through the afternoon. Slow cooling trend. Becoming very windy, especially south Washington Cascades.
Mt. Hood
Friday Scattered light rain showers this morning, chance of light rain showers this afternoon. A few sunbreaks possible beginning late morning, then becoming overcast in the afternoon. Mild.
Friday Night Cloudy. Moderate to occasionally heavy rain developing after midnight. Mild.
Saturday Stormy with moderate to locally heavy rain and snow in the morning becoming moderate rain and snow showers from late morning through the afternoon. Slow cooling trend. Very windy.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Friday Morning Snow Level 6500' 6000' 5000' ' ' 6000' ' 7000'
Friday Afternoon Snow Level 6500' 6500' 6000' ' ' 7000' ' 8000'
Friday Night Snow Level 9000' 7000' 6500' ' ' 8000' ' 10000'
Saturday Morning Snow Level 6000' 6000' 6000' ' ' 7000' ' 7000'
Saturday Afternoon Snow Level 5500' 5500' 6000' ' ' 5500' ' 5500'
Hurricane Ridge Elevation
Friday Morning Snow Level
6500'
Friday Afternoon Snow Level
6500'
Friday Night Snow Level
9000'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
5500'
Saturday Night Snow Level
4500'
Mt. Baker Elevation
Friday Morning Snow Level
6000'
Friday Afternoon Snow Level
6500'
Friday Night Snow Level
7000'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
5500'
Saturday Night Snow Level
4500'
Washington Pass Elevation
Friday Morning Snow Level
5000'
Friday Afternoon Snow Level
6000'
Friday Night Snow Level
6500'
Saturday Morning Snow Level
6000'
Saturday Afternoon Snow Level
6000'
Saturday Night Snow Level
4500'
Leavenworth Elevation
Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Saturday Morning Snow Level
'
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Stevens Pass Elevation
Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Saturday Morning Snow Level
'
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Snoqualmie Pass Elevation
Friday Morning Snow Level
6000'
Friday Afternoon Snow Level
7000'
Friday Night Snow Level
8000'
Saturday Morning Snow Level
7000'
Saturday Afternoon Snow Level
5500'
Saturday Night Snow Level
4500'
Mt. Rainier & Crystal Elevation
Friday Morning Snow Level
'
Friday Afternoon Snow Level
'
Friday Night Snow Level
'
Saturday Morning Snow Level
'
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Mt. Hood Elevation
Friday Morning Snow Level
7000'
Friday Afternoon Snow Level
8000'
Friday Night Snow Level
10000'
Saturday Morning Snow Level
7000'
Saturday Afternoon Snow Level
5500'
Saturday Night Snow Level
4500'

* 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

Wednesday Wednesday
Hurricane Ridge LT 0.25 1.00 - 1.50
Mt Baker Ski Area LT 0.25 0 - 2.00
Washington Pass LT 0.25 0 - 1.00
Stevens Pass LT 0.25 0.75 - 1.00
Snoqualmie Pass 0.25 - 0.50 1.00 - 1.50
Mission Ridge LT 0.25 0 - 0.50
Crystal Mt 0.25 - 0.50 0 - 2.00
Paradise 0.25 - 0.50 0 - 2.00
White Pass LT 0.25 0 - 1.00
Mt Hood Meadows 0 - 0.75 2.00 - 3.00
0 - 0.75 2.00 - 3.00

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Friday Morning S 10 - 20 S 10 - 20 S 5 - 15 --- - SW 5 - 15
Friday Afternoon SE 0 - 10 S 5 - 15 SE 5 - 15 --- - SE 5 - 15
Friday Night SE 15 - 25 E 10 - 20 E 15 - 25 --- - ESE 15 - 25
Saturday Morning S 25 - 45 SE 20 - 30 S 15 - 30 --- - SW 35 - 45
Saturday Afternoon S 25 - 45 SSE 25 - 35 SSW 20 - 35 --- - SW 35 - 45
Hurricane Ridge Elevation
Friday Morning S 10 - 20
Friday Afternoon SE 0 - 10
Friday Night SE 15 - 25
Saturday Morning S 25 - 45
Saturday Afternoon S 25 - 45
Saturday Night SSW 15 - 25
Mt. Baker Elevation
Friday Morning S 10 - 20
Friday Afternoon S 5 - 15
Friday Night E 10 - 20
Saturday Morning SE 20 - 30
Saturday Afternoon SSE 25 - 35
Saturday Night SE 15 - 25
Stevens and Snoqualmie Pass Elevation
Friday Morning S 5 - 15
Friday Afternoon SE 5 - 15
Friday Night E 15 - 25
Saturday Morning S 15 - 30
Saturday Afternoon SSW 20 - 35
Saturday Night S 15 - 25
Mt. Rainier Elevation
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Night --- -
Mt. Hood Elevation
Friday Morning SW 5 - 15
Friday Afternoon SE 5 - 15
Friday Night ESE 15 - 25
Saturday Morning SW 35 - 45
Saturday Afternoon SW 35 - 45
Saturday Night SW 35 - 45
Hurricane Ridge Direction - Speed
Friday Morning S 10 - 20
Friday Afternoon SE 0 - 10
Friday Night SE 15 - 25
Saturday Morning S 25 - 45
Saturday Afternoon S 25 - 45
Saturday Night SSW 15 - 25
Mt. Baker Direction - Speed
Friday Morning S 10 - 20
Friday Afternoon S 5 - 15
Friday Night E 10 - 20
Saturday Morning SE 20 - 30
Saturday Afternoon SSE 25 - 35
Saturday Night SE 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning S 5 - 15
Friday Afternoon SE 5 - 15
Friday Night E 15 - 25
Saturday Morning S 15 - 30
Saturday Afternoon SSW 20 - 35
Saturday Night S 15 - 25
Mt. Rainier Direction - Speed
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Night --- -
Mt. Hood Direction - Speed
Friday Morning SW 5 - 15
Friday Afternoon SE 5 - 15
Friday Night ESE 15 - 25
Saturday Morning SW 35 - 45
Saturday Afternoon SW 35 - 45
Saturday Night SW 35 - 45

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
Friday Morning SW 10 - 20 SW 10 - 20 SW 15 - 25 --- - SW 15 - 25
Friday Afternoon S 10 - 20 S 5 - 15 SW 10 - 20 --- - SW 10 - 20
Friday Night S 10 - 20 S 10 - 20 SSW 20 - 30 --- - SSW 25 - 35
Saturday Morning S 35 - 45 S 25 - 35 SSW 40 - 50 --- - SW 60 - 75
Saturday Afternoon SSW 30 - 40 SW 20 - 30 SSW 45 - 55 --- - SW 60 - 75
Mt. Baker Direction - Speed
Friday Morning SW 10 - 20
Friday Afternoon S 10 - 20
Friday Night S 10 - 20
Saturday Morning S 35 - 45
Saturday Afternoon SSW 30 - 40
Saturday Night S 20 - 30
Washington Pass Direction - Speed
Friday Morning SW 10 - 20
Friday Afternoon S 5 - 15
Friday Night S 10 - 20
Saturday Morning S 25 - 35
Saturday Afternoon SW 20 - 30
Saturday Night S 15 - 25
Stevens and Snoqualmie Pass Direction - Speed
Friday Morning SW 15 - 25
Friday Afternoon SW 10 - 20
Friday Night SSW 20 - 30
Saturday Morning SSW 40 - 50
Saturday Afternoon SSW 45 - 55
Saturday Night SW 30 - 40
Mt. Rainier Direction - Speed
Friday Morning --- -
Friday Afternoon --- -
Friday Night --- -
Saturday Morning --- -
Saturday Afternoon --- -
Saturday Night --- -
Mt. Hood Direction - Speed
Friday Morning SW 15 - 25
Friday Afternoon SW 10 - 20
Friday Night SSW 25 - 35
Saturday Morning SW 60 - 75
Saturday Afternoon SW 60 - 75
Saturday Night SW 60 - 75

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 Apr 5, 2018

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