Issued: 2:04 PM PST Sunday, November 27, 2022
by Robert Hahn

Jump to: Weather Forecast I Precipitation I Snow Level I 5000' Temps I Ridgeline Winds I Extended Weather

Weather Synopsis

A cold trough has settled into our region and the cold air it has brought will stick around all week. Instability showers and convergence bands rotate around the trough with decreasing westerly flow behind this morning's frontal passage. Mt. Hood should be the biggest beneficiary with moderate winds continuing to drive mountain-enhanced snowfall and we expect an additional 6-12" of low-density snow through Monday. Most of the west slopes of the Washington Cascades can expect an additional 2-6" of snow before tapering as winds die down and flow aloft switches more northerly early Monday. A few locations in the Mountain Loop could pick up higher snow within anticipated convergence between Fraser outflow winds and air moving around the Olympic Mountains. The Fraser outflow could also induce some light snowfall along the northern slope of the Olympic mountains with snow levels close to sea level. Sunshine will start to make inroads on Monday in northern areas with clouds decreasing across the region.

Monday night should be clear, dry, and cold with light E flow developing. Clouds begin streaming into the region Tuesday morning ahead of the next major system, a deep low sliding down the BC coastline from the Gulf of Alaska. Light rain and snow should start up Tuesday afternoon with snow down to sea level in northern portions of Washington State.

 

Weather Forecast

Olympics
West North
West Central
West South
Stevens Pass
Snoqualmie Pass
East North
East Central
East South
Mt. Hood
Use dropdown to select your zone
Sunday Night Light, but locally intense snow showers in the evening, then light upslope snowfall could bring several inches of snow to the foothills overnight. Cold.
Monday Light upslope snowfall ending early. Skies mostly clear by the afternoon. Continued cold.
Sunday Night Light snow showers. Cold.
Monday Mostly clear. Continued cold.
Sunday Night Mododerate snow showers/convergence during the evening may be locally heavy with significant snow totals possible. Snow showers become light overnight. Cold.
Monday Partly cloudy to mostly clear skies. Continued cold.
Sunday Night Moderate snow showers becoming light overnight. Cold.
Monday Mostly cloudy with snow showers in the morning, then partial sunshine in the afternoon. Continued cold.
Sunday Night Light to moderate snow showers/convergence becoming light. Cold. Light ridgeline and W wind at the Pass.
Monday Mostly cloudy with snow showers in the morning, then partial sunshine in the afternoon. Continued cold. Light ridgeline winds with light W or variable winds at the Pass.
Sunday Night Light to moderate snow showers/convergence becoming light. Cold. Light ridgeline and W wind at the Pass.
Monday Mostly cloudy with snow showers in the morning, then partial sunshine in the afternoon. Continued cold. Light ridgeline winds with light W or variable winds at the Pass.
Sunday Night Light snow showers. Cold.
Monday Mostly sunny. Continued cold.
Sunday Night Light snow showers and convergence spillover. Cold.
Monday A few snow showers with mostly cloudy skies to start. Partly sunny skies by the afternoon. Continued cold.
Sunday Night Light to occasionally moderate snow showers. Cold.
Monday A few snow showers with mostly cloudy skies to start. Partly sunny skies by the afternoon. Continued cold.
Sunday Night Heavy snow showers. Cold. Moderate ridgeline winds.
Monday Tapering light to occasionally moderate snow showers tapering during the afternoon. Moderate ridgeline winds. Continued cold.

Issued: 2:04 PM PST Sunday, November 27, 2022

Precipitation (in)

Sunday Night Monday Monday Night Tuesday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge LT 0.25 LT 0.10 0 LT 0.10
Mt Baker Ski Area LT 0.10 0 0 LT 0.10
Mt. Loop - Barlow Pass 0.25 - 0.50 0 0 LT 0.10
Stevens Pass 0.25 LT 0.10 0 LT 0.10
Snoqualmie Pass 0.25 - 0.50 LT 0.10 0 LT 0.10
Crystal Mt LT 0.25 LT 0.10 0 LT 0.10
Paradise 0.25 - 0.50 LT 0.10 0 LT 0.10
White Pass 0.25 - 0.50 LT 0.10 0 LT 0.10
Washington Pass LT 0.10 0 0 LT 0.10
Mission Ridge LT 0.10 LT 0.10 0 0
Salmon la Sac - Gallagher Head 0.25 LT 0.10 0 LT 0.10
Tieton River - Darland Mt. LT 0.25 LT 0.10 0 LT 0.10
Mt Hood Meadows 0.50 - 0.75 LT 0.25 LT 0.10 LT 0.10
Timberline 0.50 - 0.75 LT 0.25 LT 0.10 LT 0.10
Hurricane Ridge Precipitation (in)
Sunday Night LT 0.25
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Mt Baker Ski Area Precipitation (in)
Sunday Night LT 0.10
Monday 0
Monday Night 0
Tuesday LT 0.10
Mt. Loop - Barlow Pass Precipitation (in)
Sunday Night 0.25 - 0.50
Monday 0
Monday Night 0
Tuesday LT 0.10
Stevens Pass Precipitation (in)
Sunday Night 0.25
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Snoqualmie Pass Precipitation (in)
Sunday Night 0.25 - 0.50
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Crystal Mt Precipitation (in)
Sunday Night LT 0.25
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Paradise Precipitation (in)
Sunday Night 0.25 - 0.50
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
White Pass Precipitation (in)
Sunday Night 0.25 - 0.50
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Washington Pass Precipitation (in)
Sunday Night LT 0.10
Monday 0
Monday Night 0
Tuesday LT 0.10
Mission Ridge Precipitation (in)
Sunday Night LT 0.10
Monday LT 0.10
Monday Night 0
Tuesday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Sunday Night 0.25
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Tieton River - Darland Mt. Precipitation (in)
Sunday Night LT 0.25
Monday LT 0.10
Monday Night 0
Tuesday LT 0.10
Mt Hood Meadows Precipitation (in)
Sunday Night 0.50 - 0.75
Monday LT 0.25
Monday Night LT 0.10
Tuesday LT 0.10
Timberline Precipitation (in)
Sunday Night 0.50 - 0.75
Monday LT 0.25
Monday Night LT 0.10
Tuesday LT 0.10

Issued: 2:04 PM PST Sunday, November 27, 2022

Snow Level (ft)

Sunday Evening Sunday Night Monday Morning Monday Afternoon Monday Evening* Monday Night* Tuesday Morning* Tuesday Afternoon*
Olympics 1500' 1000' 500' 500' 500' 0 0 500'
West North 0 0 0 500' 0 0 0 0
West Central 500' 500' 1000' 1000' 0 0 0 0
West South 1000' 1000' 500' 1000' 500' 0 0 0
Stevens Pass 500' 0 0 1000' 500' 0 0 0
Snoqualmie Pass 1000' 500' 0 1500' 500' 0 0 0
East North 0 0 0 0 0 0 0 0
East Central 500' 0 0 1000' 500' 0 0 0
East South 1500' 0 0 1500' 1000' 0 0 0
Mt. Hood 2500' 2000' 1500' 1500' 1000' 500' 500' 1000'
Olympics Elevation
Sunday Evening 1500'
Sunday Night 1000'
Monday Morning 500'
Monday Afternoon 500'
Monday Evening* 500'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 500'
West North Elevation
Sunday Evening 0'
Sunday Night 0'
Monday Morning 0'
Monday Afternoon 500'
Monday Evening* 0'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
West Central Elevation
Sunday Evening 500'
Sunday Night 500'
Monday Morning 1000'
Monday Afternoon 1000'
Monday Evening* 0'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
West South Elevation
Sunday Evening 1000'
Sunday Night 1000'
Monday Morning 500'
Monday Afternoon 1000'
Monday Evening* 500'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
Stevens Pass Elevation
Sunday Evening 500'
Sunday Night 0'
Monday Morning 0'
Monday Afternoon 1000'
Monday Evening* 500'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
Snoqualmie Pass Elevation
Sunday Evening 1000'
Sunday Night 500'
Monday Morning 0'
Monday Afternoon 1500'
Monday Evening* 500'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
East North Elevation
Sunday Evening 0'
Sunday Night 0'
Monday Morning 0'
Monday Afternoon 0'
Monday Evening* 0'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
East Central Elevation
Sunday Evening 500'
Sunday Night 0'
Monday Morning 0'
Monday Afternoon 1000'
Monday Evening* 500'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
East South Elevation
Sunday Evening 1500'
Sunday Night 0'
Monday Morning 0'
Monday Afternoon 1500'
Monday Evening* 1000'
Monday Night* 0'
Tuesday Morning* 0'
Tuesday Afternoon* 0'
Mt. Hood Elevation
Sunday Evening 2500'
Sunday Night 2000'
Monday Morning 1500'
Monday Afternoon 1500'
Monday Evening* 1000'
Monday Night* 500'
Tuesday Morning* 500'
Tuesday Afternoon* 1000'

Issued: 2:04 PM PST Sunday, November 27, 2022

5000' Temperatures (°F)

Sunday Night Monday
Max / Min Max / Min
Olympics 20 / 14 14 / 6
West North 16 / 9 14 / 6
West Central 19 / 15 20 / 11
West South 21 / 18 22 / 14
Stevens Pass 19 / 16 18 / 15
Snoqualmie Pass 21 / 16 21 / 10
East North 14 / 8 13 / 2
East Central 18 / 15 18 / 14
East South 20 / 17 23 / 16
Mt. Hood 25 / 22 23 / 18
Olympics 5000' Temperature Forecast
(Max / Min)
Sunday Night 20 / 14
Monday 14 / 6
West North 5000' Temperature Forecast
(Max / Min)
Sunday Night 16 / 9
Monday 14 / 6
West Central 5000' Temperature Forecast
(Max / Min)
Sunday Night 19 / 15
Monday 20 / 11
West South 5000' Temperature Forecast
(Max / Min)
Sunday Night 21 / 18
Monday 22 / 14
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Sunday Night 19 / 16
Monday 18 / 15
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Sunday Night 21 / 16
Monday 21 / 10
East North 5000' Temperature Forecast
(Max / Min)
Sunday Night 14 / 8
Monday 13 / 2
East Central 5000' Temperature Forecast
(Max / Min)
Sunday Night 18 / 15
Monday 18 / 14
East South 5000' Temperature Forecast
(Max / Min)
Sunday Night 20 / 17
Monday 23 / 16
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Sunday Night 25 / 22
Monday 23 / 18

Issued: 2:04 PM PST Sunday, November 27, 2022

Ridgeline Winds (mph)

Sunday Evening Sunday Night Monday Morning Monday Afternoon
Olympics WSW 5-15 NW 5-15 NE 5-15 NNE 0-10
West North W 5-15 NE 0-10 NE 5-15 NE 5-15
West Central W 5-15 SW 5-15 SE 0-10 NW 0-10
West South W 5-15 WSW 5-15 NW 5-15 NW 5-15
Stevens Pass W 5-15 SW 0-10 S 0-10 WNW 0-10
Snoqualmie Pass WNW 10-20 W 5-15 WNW 5-15 WNW 5-15
East North WNW 5-15 ENE 0-10 NNW 0-10 NNW 5-15
East Central WNW 10-20 W 5-15 W 0-10 WNW 5-15
East South W 5-15 W 5-15 NW 5-15 WNW 5-15
Mt. Hood W 15-25 W 15-25 WNW 10-20 WNW 15-25
Olympics Ridgeline Winds (mph)
Sunday Evening WSW 5-15
Sunday Night NW 5-15
Monday Morning NE 5-15
Monday Afternoon NNE 0-10
West North Ridgeline Winds (mph)
Sunday Evening W 5-15
Sunday Night NE 0-10
Monday Morning NE 5-15
Monday Afternoon NE 5-15
West Central Ridgeline Winds (mph)
Sunday Evening W 5-15
Sunday Night SW 5-15
Monday Morning SE 0-10
Monday Afternoon NW 0-10
West South Ridgeline Winds (mph)
Sunday Evening W 5-15
Sunday Night WSW 5-15
Monday Morning NW 5-15
Monday Afternoon NW 5-15
Stevens Pass Ridgeline Winds (mph)
Sunday Evening W 5-15
Sunday Night SW 0-10
Monday Morning S 0-10
Monday Afternoon WNW 0-10
Snoqualmie Pass Ridgeline Winds (mph)
Sunday Evening WNW 10-20
Sunday Night W 5-15
Monday Morning WNW 5-15
Monday Afternoon WNW 5-15
East North Ridgeline Winds (mph)
Sunday Evening WNW 5-15
Sunday Night ENE 0-10
Monday Morning NNW 0-10
Monday Afternoon NNW 5-15
East Central Ridgeline Winds (mph)
Sunday Evening WNW 10-20
Sunday Night W 5-15
Monday Morning W 0-10
Monday Afternoon WNW 5-15
East South Ridgeline Winds (mph)
Sunday Evening W 5-15
Sunday Night W 5-15
Monday Morning NW 5-15
Monday Afternoon WNW 5-15
Mt. Hood Ridgeline Winds (mph)
Sunday Evening W 15-25
Sunday Night W 15-25
Monday Morning WNW 10-20
Monday Afternoon WNW 15-25

Issued: 2:04 PM PST Sunday, November 27, 2022

Extended Weather Synopsis

With cold air in place and a potent low moving toward our region, expect the snow to pile up. Easterly gradients and winds increase as the system spreads moderate to heavy snowfall into the Western Olympics Tuesday evening with moderate snow reaching the Cascades overnight. We'll have to watch the potential for a significant upslope event on the east side of the Cascade. Shower activity continues on SW flow on Wednesday as the low moves near the northern tip of Vancouver Island. Snow showers ease by Thursday morning with the low positioned just off the Oregon Coast.

Extended Snow Level (ft)

Tuesday Night* Wednesday * Wednesday Night* Thursday
West North 0 0 0 0
Snoqualmie Pass 0 0 500' 500'
Mt. Hood 1000' 2500' 2500' 1500'
West North Elevation
Tuesday Night* 0'
Wednesday * 0'
Wednesday Night* 0'
Thursday 0'
Snoqualmie Pass Elevation
Tuesday Night* 0'
Wednesday * 0'
Wednesday Night* 500'
Thursday 500'
Mt. Hood Elevation
Tuesday Night* 1000'
Wednesday * 2500'
Wednesday Night* 2500'
Thursday 1500'

Jump to: Weather Forecast I Precipitation I Snow Level I 5000' Temps I Ridgeline Winds I Extended Weather

Previous forecast from Nov 27, 2022

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.

The 5000’ temperature forecast does not imply a trend over the 12 hr period and only represents the max and min temperatures within a 12 hr period in the zone. The 6-hr snow level forecast, the forecast discussion, and weather forecast sections may add detail regarding temperature trends.

The snow level forecast represents the general snow level over a 6 hr time period. Freezing levels are forecast when precipitation is not expected.

*Easterly or offshore flow is highlighted with an asterisk when we expect relatively cool east winds in the major Cascade Passes. Easterly flow will often lead to temperature inversions and is a key variable for forecasting precipitation type in the Cascade Passes. Strong easterly flow events can affect terrain on a more regional scale.

Ridgeline winds are the average wind speed and direction over a 6 hr time period.

The wind forecast represents an elevation range instead of a single elevation slice. The elevation range overlaps with the near and above treeline elevation bands in the avalanche forecast and differs per zone.

Wind direction indicates the direction the wind originates or comes from on the 16-point compass rose.

Water Equivalent (WE) is the liquid water equivalent of all precipitation types; rain, snow, ice pellets, etc., forecast to the hundredth of an inch at specific locations. To use WE as a proxy for snowfall amounts, start with a snow to water ratio of 10:1 (10 inches of snow = 1 inch WE). Temperatures at or near freezing will generally have a lower ratio (heavy wet snow) and very cold temperatures can have a much higher ratio (dry fluffy snow).

The label LT, is shorthand for ‘less than’.