Issued: 7:14 PM PDT Saturday, March 24, 2018
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 Saturday & Sunday

A slow-moving, deep and broad trough sits over the Pacific Northwest and near shore waters on Saturday afternoon.

The Pacific Northwest is being influenced by two features: (1) An open low off the Oregon Coast that is wrapping moisture around it as it tracks SE and (2) A weak low moving away from the region, currently over NE Washington, with insignificant lingering shower activity over the North and Central Cascade West slopes. The moisture from the open low has drifted farther north than initially and will bring light to moderate snow showers to Mt. Hood and the South Cascades with S or E winds at low levels. Accumulating snow is expected as far north as the Mt. Rainier area from this feature and snowfall will continue into the evening hours in the Washington Cascades and will gradually taper during the early morning hours at Mt. Hood.

Cloudy skies are expected south of Snoqualmie Pass and mostly cloudy skies with shallow cumulus clouds will be present elsewhere. 

Sunday will see increasing clouds ahead of an upper level trough arriving on NW flow that will bring increasing light snow to the region very late on Sunday night.

Weather Forecast

Olympics
Saturday Snow showers possible.
Saturday Night Clear skies.
Sunday Increasing clouds with a chance of a snow shower by evening.
Washington Cascades near and west of the Crest including Stevens, Snoqualmie and White Passes
Saturday Mostly cloudy skies with very light snow showers along the west slopes of the Cascades from Snoqualmie northward. Cloudy in the south with light to moderate snow possible from Mt. Rainier southward.
Saturday Night Clearing skies.
Sunday Scattered, but increasing, cloud-cover. Chance of a snow shower by evening.
East Slopes of the Washington Cascades
Saturday Cloudy in the south. Partly cloudy in central and north parts.
Saturday Night Clear skies.
Sunday Scattered, but increasing, cloud-cover.
Mt. Hood
Saturday Light to moderate snow.
Saturday Night Periods of light to moderate snow, decreasing after midnight and ending by morning.
Sunday Mostly cloudy.

Snow/Freezing Level (ft)

Hurricane Ridge Mt. Baker Washington Pass Leavenworth Stevens Pass Snoqualmie Pass Mt. Rainier, Crystal & White Pass Mt. Hood
Saturday Afternoon Snow Level 2000' 2000' 2500' ' ' 2500' ' 2500'
Saturday Night Snow Level 1500' 1000' 1000' ' ' 1000' ' 2000'
Sunday Morning Snow Level 1500' 1500' 2000' ' ' 2000' ' 2500'
Sunday Afternoon Snow Level 2000' 2500' 3000' ' ' 2500' ' 3000'
Hurricane Ridge Elevation
Saturday Afternoon Snow Level
2000'
Saturday Night Snow Level
1500'
Sunday Morning Snow Level
1500'
Sunday Afternoon Snow Level
2000'
Sunday Night Snow Level
2500'
Mt. Baker Elevation
Saturday Afternoon Snow Level
2000'
Saturday Night Snow Level
1000'
Sunday Morning Snow Level
1500'
Sunday Afternoon Snow Level
2500'
Sunday Night Snow Level
1500'
Washington Pass Elevation
Saturday Afternoon Snow Level
2500'
Saturday Night Snow Level
1000'
Sunday Morning Snow Level
2000'
Sunday Afternoon Snow Level
3000'
Sunday Night Snow Level
1000'
Leavenworth Elevation
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Sunday Morning Snow Level
'
Sunday Afternoon Snow Level
'
Sunday Night Snow Level
'
Stevens Pass Elevation
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Sunday Morning Snow Level
'
Sunday Afternoon Snow Level
'
Sunday Night Snow Level
'
Snoqualmie Pass Elevation
Saturday Afternoon Snow Level
2500'
Saturday Night Snow Level
1000'
Sunday Morning Snow Level
2000'
Sunday Afternoon Snow Level
2500'
Sunday Night Snow Level
1500'
Mt. Rainier & Crystal Elevation
Saturday Afternoon Snow Level
'
Saturday Night Snow Level
'
Sunday Morning Snow Level
'
Sunday Afternoon Snow Level
'
Sunday Night Snow Level
'
Mt. Hood Elevation
Saturday Afternoon Snow Level
2500'
Saturday Night Snow Level
2000'
Sunday Morning Snow Level
2500'
Sunday Afternoon Snow Level
3000'
Sunday Night 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 Sunday
Hurricane Ridge LT 0.10 LT 0.10
Mt Baker Ski Area LT 0.10 LT 0.25
Washington Pass LT 0.10 LT 0.10
Stevens Pass LT 0.25 LT 0.10
Snoqualmie Pass LT 0.25 LT 0.25
Mission Ridge LT 0.10 LT 0.10
Crystal Mt LT 0.25 LT 0.10
Paradise 0.25 - 0.50 LT 0.25
White Pass 0.25 - 0.50 LT 0.10
Mt Hood Meadows 0.25 - 0.50 LT 0.10
0.25 - 0.50 LT 0.10

Free Winds at 5000' (mph)

Hurricane Ridge Mt. Baker Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Saturday Afternoon W 5 - 15 WSW 5 - 15 WSW 5 - 15 --- - E 5 - 15
Saturday Night W 5 - 15 WSW 5 - 15 W 5 - 15 --- - W 10 - 20
Sunday Morning WSW 10 - 20 SW 5 - 15 WSW 10 - 20 --- - WSW 15 - 25
Sunday Afternoon WSW 10 - 20 WSW 10 - 20 WSW 15 - 25 --- - WSW 15 - 25
Hurricane Ridge Elevation
Saturday Afternoon W 5 - 15
Saturday Night W 5 - 15
Sunday Morning WSW 10 - 20
Sunday Afternoon WSW 10 - 20
Sunday Night WSW 10 - 20
Mt. Baker Elevation
Saturday Afternoon WSW 5 - 15
Saturday Night WSW 5 - 15
Sunday Morning SW 5 - 15
Sunday Afternoon WSW 10 - 20
Sunday Night SSW 10 - 20
Stevens and Snoqualmie Pass Elevation
Saturday Afternoon WSW 5 - 15
Saturday Night W 5 - 15
Sunday Morning WSW 10 - 20
Sunday Afternoon WSW 15 - 25
Sunday Night WSW 20 - 30
Mt. Rainier Elevation
Saturday Afternoon --- -
Saturday Night --- -
Sunday Morning --- -
Sunday Afternoon --- -
Sunday Night --- -
Mt. Hood Elevation
Saturday Afternoon E 5 - 15
Saturday Night W 10 - 20
Sunday Morning WSW 15 - 25
Sunday Afternoon WSW 15 - 25
Sunday Night WSW 20 - 30
Hurricane Ridge Direction - Speed
Saturday Afternoon W 5 - 15
Saturday Night W 5 - 15
Sunday Morning WSW 10 - 20
Sunday Afternoon WSW 10 - 20
Sunday Night WSW 10 - 20
Mt. Baker Direction - Speed
Saturday Afternoon WSW 5 - 15
Saturday Night WSW 5 - 15
Sunday Morning SW 5 - 15
Sunday Afternoon WSW 10 - 20
Sunday Night SSW 10 - 20
Stevens and Snoqualmie Pass Direction - Speed
Saturday Afternoon WSW 5 - 15
Saturday Night W 5 - 15
Sunday Morning WSW 10 - 20
Sunday Afternoon WSW 15 - 25
Sunday Night WSW 20 - 30
Mt. Rainier Direction - Speed
Saturday Afternoon --- -
Saturday Night --- -
Sunday Morning --- -
Sunday Afternoon --- -
Sunday Night --- -
Mt. Hood Direction - Speed
Saturday Afternoon E 5 - 15
Saturday Night W 10 - 20
Sunday Morning WSW 15 - 25
Sunday Afternoon WSW 15 - 25
Sunday 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.

Free Winds at 9000' (mph)

Mt. Baker Washington Pass Stevens to Snoqualmie Pass Mt. Rainier Mt. Hood
Saturday Afternoon W 10 - 20 W 10 - 20 WSW 20 - 30 --- - WSW 15 - 25
Saturday Night W 10 - 20 W 10 - 20 W 15 - 25 --- - SSW 15 - 25
Sunday Morning WSW 15 - 25 WSW 10 - 20 WSW 20 - 30 --- - W 20 - 30
Sunday Afternoon WSW 20 - 30 W 15 - 25 W 25 - 35 --- - W 25 - 35
Mt. Baker Direction - Speed
Saturday Afternoon W 10 - 20
Saturday Night W 10 - 20
Sunday Morning WSW 15 - 25
Sunday Afternoon WSW 20 - 30
Sunday Night W 20 - 30
Washington Pass Direction - Speed
Saturday Afternoon W 10 - 20
Saturday Night W 10 - 20
Sunday Morning WSW 10 - 20
Sunday Afternoon W 15 - 25
Sunday Night W 25 - 35
Stevens and Snoqualmie Pass Direction - Speed
Saturday Afternoon WSW 20 - 30
Saturday Night W 15 - 25
Sunday Morning WSW 20 - 30
Sunday Afternoon W 25 - 35
Sunday Night W 25 - 35
Mt. Rainier Direction - Speed
Saturday Afternoon --- -
Saturday Night --- -
Sunday Morning --- -
Sunday Afternoon --- -
Sunday Night --- -
Mt. Hood Direction - Speed
Saturday Afternoon WSW 15 - 25
Saturday Night SSW 15 - 25
Sunday Morning W 20 - 30
Sunday Afternoon W 25 - 35
Sunday Night W 30 - 40

Extended Weather Synopsis for Sunday night through Sunday

A shortwave trough on NW flow arrives arrives over a broad, but shallow ridge on Monday bringing increasing rain and snow through focused on Washington state through Tuesday along with gradually rising snow levels as the ridge continues to gradually shift E into the region. A warm front is expected to pass Monday evening with a wind shift from W-SW to W.

The ridge builds further Tuesday night and Wednesday as more moisture continues to spill over the ridge.

 

Extended Weather

Olympics, Washington Cascades and Mt. Hood Area
Monday Increasing light rain/snow in the morning becoming light to occasional moderate in the afternoon. W-SW crest-level winds in the light to moderate range. Rain and snow increasing overnight becomes moderate intensity as winds shift westerly. Tuesday Moderate rain and snow decreasing, becoming light in the north Cascades and Hood regions. Light to occasional moderate rain and snow Tuesday night. Wednesday Light to occasional moderate rain and snow shifting northward and focusing mainly on the north and central Cascades.

Extended Snow/Freezing Levels

Mt. Baker Snoqualmie Pass Mt. Hood Easterly Flow *
Monday Snow Level 2000' - 4000' 2000' - 4000' 2000' - 4000'
Monday Night Snow Level 4000' - 5000' 4000' - 5000' 5000' - 6000'
Tuesday Snow Level 3500' - 5500' 4000' - 5000' 5000' - 6000'
Tuesday Night Snow Level 3000' - 4000' 4000' - 5000' 5000' - 6000'
Mt. Baker Elevation
Monday Snow Level
2000' - 4000'
Monday Night Snow Level
4000' - 5000'
Tuesday Snow Level
3500' - 5500'
Tuesday Night Snow Level
3000' - 4000'
Wednesday Snow Level
4000' - 5000'
Snoqualmie Pass Elevation
Monday Snow Level
2000' - 4000'
Monday Night Snow Level
4000' - 5000'
Tuesday Snow Level
4000' - 5000'
Tuesday Night Snow Level
4000' - 5000'
Wednesday Snow Level
4000' - 5000'
Mt. Hood Elevation
Monday Snow Level
2000' - 4000'
Monday Night Snow Level
5000' - 6000'
Tuesday Snow Level
5000' - 6000'
Tuesday Night Snow Level
5000' - 6000'
Wednesday Snow Level
5000' - 6000'

* 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 Mar 24, 2018

The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.