Issued: 1:59 PM PST Monday, November 15, 2021
by Dallas Glass

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

Weather Synopsis

Welcome to the first mountain weather forecast for the 2021-2022 winter season! We will issue daily mountain weather forecasts at 2 pm until full operations begin. Make sure to check the General Avalanche Statements, issued Monday, Wednesday, and Friday at 6pm, for the latest on region-wide snow and avalanche conditions. 

A strong atmospheric river remains focused on the region this afternoon with very heavy rain, high snow levels, and extremely strong winds impacting the mountains. Early this evening, a fast-moving cold front will sweep over the area causing temperatures to plummet and snow levels to rapidly decrease. As they do, snow will return to most of our mountain trailheads. The question remains, how much precipitation will fall as snow following the cooldown? The answer largely depends on your location. A Puget Sound Convergence Zone will likely bring locally heavier amounts of precipitation to the Mountain Loop and Stevens Pass areas. As the upper airflow turns more northwesterly, this concentrated band of snow will drift further south towards Snoqualmie Pass. For the remainder of the mountain areas, more modest snow showers should continue overnight and into Tuesday, particularly for areas near and west of the Cascade Crest and close to the high volcanoes. Strong winds associated with this cold front will also continue to impact the mountains overnight and into Tuesday morning. Expect strong to very strong ridgetop winds combining with precipitation to produce very stormy conditions with low visibility. As the system pushes further east on Tuesday, winds should become more northwesterly and decrease for most areas. 

By late Tuesday afternoon/evening cold and dry northwesterly winds should allow the region a needed break from the recent stormy weather. A weak high-pressure ridge appears to move over the Pacific Northwest Tuesday night through Wednesday. Cool temperatures, mostly to partly cloudy skies, and light winds will prevail for the remainder of the short-term forecast. 

 

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
Monday Night Snow levels quickly dropping during the evening. Cloudy with snow showers. Very strong westerly winds gradually decreasing overnight.
Tuesday Mostly cloudy in the morning with some clearing in the afternoon. Isolated showers. Winds continuing to decrease.
Monday Night Snow levels quickly dropping during the evening. Cloudy with snow showers. Strong westerly winds gradually decreasing overnight.
Tuesday Moslty cloudy with snow showers. Light to moderate westerly winds.
Monday Night Snow levels quickly dropping during the evening. Puget sound convergence zone could bring periods of heavy precipitation. Very strong westerly winds gradually decreasing overnight.
Tuesday Cloudy with continued snow showers, heaviest in the morning. Moderate westerly winds continuing to decrease.
Monday Night Snow levels quickly dropping during the evening. Snow becoming more showery overnight. Storng westerly winds gradually decreasing.
Tuesday Cloudy with some sun breaks possible in the afternoon. Showers lingering especially in the morning and near the volcanoes. Moderate westerly winds continuing to decrease.
Monday Night Snow levels quickly dropping during the evening. Puget sound convergence zone could bring periods of heavy precipitation. Strong westerly winds gradually decreasing overnight.
Tuesday Cloudy with snow showers. Light to moderate westerly winds.
Monday Night Snow levels quickly dropping during the evening. Puget sound convergence zone could bring periods of heavy precipitation. Very strong westerly winds gradually decreasing overnight.
Tuesday Cloudy with snow showers, heaviest in the morning. Moderate westerly winds gradually decreasing.
Monday Night Snow levels quickly dropping during the evening. Cloudy with snow showers gradually decreasing. Very strong westerly winds gradually decreasing.
Tuesday Mostly cloudy with some clearing in the afternoon. Isolated snow showers. Moderate westerly winds.
Monday Night Snow levels quickly dropping during the evening. Cloudy with snow showers heaviest near the Cascade crest. Very strong westerly winds gradually decreasing.
Tuesday Mostly cloudy with some clearing in the afternoon. Isolated snow showers. Strong WNW winds gradually decreasing.
Monday Night Snow levels quickly dropping during the evening. Cloudy with snow showers heaviest near the Cascade crest. Very strong westerly winds gradually decreasing.
Tuesday Mostly cloudy with some clearing in the afternoon. Isolated snow showers. Strong WNW winds gradually decreasing.
Monday Night Snow levels quickly dropping during the evening. Cloudy with snow, moderate to heavy at times. Very strong westerly winds gradually decreasing.
Tuesday Cloudy with isolated snow showers. Moderate to strong NW winds gradually decreasing.

Precipitation (in)

Monday Night Tuesday Tuesday Night Wednesday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0.25 LT 0.10 0 0
Mt Baker Ski Area 0.50 LT 0.25 0 0
Mt. Loop - Barlow Pass 0.75 -1.00 0.25 - 0.50 0 0
Stevens Pass 0.75 -1.00 0.25 0 0
Snoqualmie Pass 0.50 - 0.75 0.25 0 0
Crystal Mt 0.25 - 0.50 LT 0.10 0 0
Paradise 0.75 LT 0.25 0 0
White Pass 0.50 LT 0.25 0 0
Washington Pass 0.25 LT 0.10 0 0
Mission Ridge LT 0.10 LT 0.10 0 0
Salmon la Sac - Gallagher Head 0.50 LT 0.25 0 0
Tieton River - Darland Mt. 0.25 LT 0.10 0 0
Mt Hood Meadows 0.50 LT 0.25 0 0
Timberline 0.50 - 0.75 LT 0.25 0 0
Hurricane Ridge Precipitation (in)
Monday Night 0.25
Tuesday LT 0.10
Tuesday Night 0
Wednesday 0
Mt Baker Ski Area Precipitation (in)
Monday Night 0.50
Tuesday LT 0.25
Tuesday Night 0
Wednesday 0
Mt. Loop - Barlow Pass Precipitation (in)
Monday Night 0.75 -1.00
Tuesday 0.25 - 0.50
Tuesday Night 0
Wednesday 0
Stevens Pass Precipitation (in)
Monday Night 0.75 -1.00
Tuesday 0.25
Tuesday Night 0
Wednesday 0
Snoqualmie Pass Precipitation (in)
Monday Night 0.50 - 0.75
Tuesday 0.25
Tuesday Night 0
Wednesday 0
Crystal Mt Precipitation (in)
Monday Night 0.25 - 0.50
Tuesday LT 0.10
Tuesday Night 0
Wednesday 0
Paradise Precipitation (in)
Monday Night 0.75
Tuesday LT 0.25
Tuesday Night 0
Wednesday 0
White Pass Precipitation (in)
Monday Night 0.50
Tuesday LT 0.25
Tuesday Night 0
Wednesday 0
Washington Pass Precipitation (in)
Monday Night 0.25
Tuesday LT 0.10
Tuesday Night 0
Wednesday 0
Mission Ridge Precipitation (in)
Monday Night LT 0.10
Tuesday LT 0.10
Tuesday Night 0
Wednesday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Monday Night 0.50
Tuesday LT 0.25
Tuesday Night 0
Wednesday 0
Tieton River - Darland Mt. Precipitation (in)
Monday Night 0.25
Tuesday LT 0.10
Tuesday Night 0
Wednesday 0
Mt Hood Meadows Precipitation (in)
Monday Night 0.50
Tuesday LT 0.25
Tuesday Night 0
Wednesday 0
Timberline Precipitation (in)
Monday Night 0.50 - 0.75
Tuesday LT 0.25
Tuesday Night 0
Wednesday 0

Snow Level (ft)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon Tuesday Evening Tuesday Night* Wednesday Morning* Wednesday Afternoon*
Olympics 3000' 2500' 2500' 2500' 1500' 1500' 2000' 3000'
West North 2500' 1500' 2000' 2000' 1000' 1000' 1500' 3000'
West Central 2500' 2000' 2000' 2500' 1500' 1500' 2000' 3500'
West South 2500' 2000' 2000' 2500' 1500' 1500' 2500' 4000'
Stevens Pass 2500' 2000' 2000' 2500' 1500' 1500' 2000' 3000'
Snoqualmie Pass 2500' 2000' 2000' 2500' 1500' 1500' 2000' 3500'
East North 2500' 1500' 1500' 2000' 1000' 1000' 1500' 2500'
East Central 2500' 2000' 2000' 2500' 1000' 1000' 2000' 3000'
East South 3000' 2000' 2000' 2500' 1500' 1500' 2500' 4000'
Mt. Hood 3500' 2500' 2500' 3000' 2500' 2000' 3000' 4000'
Olympics Elevation
Monday Evening 3000'
Monday Night 2500'
Tuesday Morning 2500'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night* 1500'
Wednesday Morning* 2000'
Wednesday Afternoon* 3000'
West North Elevation
Monday Evening 2500'
Monday Night 1500'
Tuesday Morning 2000'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night* 1000'
Wednesday Morning* 1500'
Wednesday Afternoon* 3000'
West Central Elevation
Monday Evening 2500'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night* 1500'
Wednesday Morning* 2000'
Wednesday Afternoon* 3500'
West South Elevation
Monday Evening 2500'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night* 1500'
Wednesday Morning* 2500'
Wednesday Afternoon* 4000'
Stevens Pass Elevation
Monday Evening 2500'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night* 1500'
Wednesday Morning* 2000'
Wednesday Afternoon* 3000'
Snoqualmie Pass Elevation
Monday Evening 2500'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night* 1500'
Wednesday Morning* 2000'
Wednesday Afternoon* 3500'
East North Elevation
Monday Evening 2500'
Monday Night 1500'
Tuesday Morning 1500'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night* 1000'
Wednesday Morning* 1500'
Wednesday Afternoon* 2500'
East Central Elevation
Monday Evening 2500'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1000'
Tuesday Night* 1000'
Wednesday Morning* 2000'
Wednesday Afternoon* 3000'
East South Elevation
Monday Evening 3000'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night* 1500'
Wednesday Morning* 2500'
Wednesday Afternoon* 4000'
Mt. Hood Elevation
Monday Evening 3500'
Monday Night 2500'
Tuesday Morning 2500'
Tuesday Afternoon 3000'
Tuesday Evening 2500'
Tuesday Night* 2000'
Wednesday Morning* 3000'
Wednesday Afternoon* 4000'

5000' Temperatures (°F)

Monday Night Tuesday
Max / Min Max / Min
Olympics 32 / 21 23 / 19
West North 31 / 21 22 / 20
West Central 33 / 23 22 / 21
West South 34 / 23 26 / 21
Stevens Pass 33 / 22 23 / 20
Snoqualmie Pass 34 / 23 23 / 21
East North 33 / 20 22 / 17
East Central 34 / 22 24 / 20
East South 35 / 23 25 / 19
Mt. Hood 33 / 25 27 / 21
Olympics 5000' Temperature Forecast
(Max / Min)
Monday Night 32 / 21
Tuesday 23 / 19
West North 5000' Temperature Forecast
(Max / Min)
Monday Night 31 / 21
Tuesday 22 / 20
West Central 5000' Temperature Forecast
(Max / Min)
Monday Night 33 / 23
Tuesday 22 / 21
West South 5000' Temperature Forecast
(Max / Min)
Monday Night 34 / 23
Tuesday 26 / 21
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 33 / 22
Tuesday 23 / 20
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 34 / 23
Tuesday 23 / 21
East North 5000' Temperature Forecast
(Max / Min)
Monday Night 33 / 20
Tuesday 22 / 17
East Central 5000' Temperature Forecast
(Max / Min)
Monday Night 34 / 22
Tuesday 24 / 20
East South 5000' Temperature Forecast
(Max / Min)
Monday Night 35 / 23
Tuesday 25 / 19
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday Night 33 / 25
Tuesday 27 / 21

Ridgeline Winds (mph)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon
Olympics W 35-50 W 20-30 W 15-25 WNW 5-15
West North W 30-40 W 20-30 W 15-25 WNW 5-15
West Central W 35-50 W 25-35 W 20-30 NW 10-20
West South W 30-40 W 25-35 W 20-30 WNW 10-20
Stevens Pass W 30-40 W 25-35 W 15-25 WNW 10-20
Snoqualmie Pass W 35-50 W 30-40 WNW 20-30 NW 15-25
East North W 40-55 W 35-50 W 20-30 WNW 10-20
East Central W 45-65 WNW 40-55 WNW 35-50 WNW 25-35
East South W 40-55 WNW 40-55 NW 35-50 WNW 20-30
Mt. Hood W 40-55 WNW 35-50 WNW 30-40 NW 20-30
Olympics Ridgeline Winds (mph)
Monday Evening W 35-50
Monday Night W 20-30
Tuesday Morning W 15-25
Tuesday Afternoon WNW 5-15
West North Ridgeline Winds (mph)
Monday Evening W 30-40
Monday Night W 20-30
Tuesday Morning W 15-25
Tuesday Afternoon WNW 5-15
West Central Ridgeline Winds (mph)
Monday Evening W 35-50
Monday Night W 25-35
Tuesday Morning W 20-30
Tuesday Afternoon NW 10-20
West South Ridgeline Winds (mph)
Monday Evening W 30-40
Monday Night W 25-35
Tuesday Morning W 20-30
Tuesday Afternoon WNW 10-20
Stevens Pass Ridgeline Winds (mph)
Monday Evening W 30-40
Monday Night W 25-35
Tuesday Morning W 15-25
Tuesday Afternoon WNW 10-20
Snoqualmie Pass Ridgeline Winds (mph)
Monday Evening W 35-50
Monday Night W 30-40
Tuesday Morning WNW 20-30
Tuesday Afternoon NW 15-25
East North Ridgeline Winds (mph)
Monday Evening W 40-55
Monday Night W 35-50
Tuesday Morning W 20-30
Tuesday Afternoon WNW 10-20
East Central Ridgeline Winds (mph)
Monday Evening W 45-65
Monday Night WNW 40-55
Tuesday Morning WNW 35-50
Tuesday Afternoon WNW 25-35
East South Ridgeline Winds (mph)
Monday Evening W 40-55
Monday Night WNW 40-55
Tuesday Morning NW 35-50
Tuesday Afternoon WNW 20-30
Mt. Hood Ridgeline Winds (mph)
Monday Evening W 40-55
Monday Night WNW 35-50
Tuesday Morning WNW 30-40
Tuesday Afternoon NW 20-30

Extended Weather Synopsis

While the area should begin the extended forecast period cool and dry, increasing clouds Wednesday afternoon and evening will hint at the weather changes to come. A storm system appears to approach the coast on Thursday, spreading precipitation from SW to NE as it draws nearer. A warm front associated with the initial precipitation may bring rain to many of our mountain areas before a trailing cold front returns snow to the region. At the moment the bulk of the stormy weather appears to impact the mountains Thursday night with showers lingering into Friday. 

Extended Snow Level (ft)

Wednesday Night* Thursday * Thursday Night* Friday *
West North 1500' 3000' 3000' 2500'
Snoqualmie Pass 2000' 3000' 3500' 3000'
Mt. Hood 2500' 4500' 4500' 4000'
West North Elevation
Wednesday Night* 1500'
Thursday * 3000'
Thursday Night* 3000'
Friday * 2500'
Snoqualmie Pass Elevation
Wednesday Night* 2000'
Thursday * 3000'
Thursday Night* 3500'
Friday * 3000'
Mt. Hood Elevation
Wednesday Night* 2500'
Thursday * 4500'
Thursday Night* 4500'
Friday * 4000'

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

Previous forecast from May 2, 2021

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’.