Issued: 2:04 PM PST Friday, November 17, 2023
by Robert Hahn

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

Weather Synopsis

Following a mostly sunny workweek, the ridge responsible for these conditions shifts eastward on Saturday, making way for a storm system and the type of weather we typically associate with November - rain, snow, and some wind. Mostly clear skies remain Friday night with continued mild temperatures aloft and cooler air settling into valley locations. Increasing light to moderate E winds likely maintain below-freezing temperatures at Snoqualmie Pass. However, the next system should mix up the air mass, gradually decreasing the inverted atmospheric conditions on Saturday. A stationary low pressure off the California coast joins an approaching storm system ushering in a sharp change in the weather. Saturday should be mild but pleasant in the mountains with increasing SSW winds. The approaching frontal system will transition our skies from mostly sunny to mostly cloudy throughout the day. The southern Cascade Volcanoes and Olympics can expect light rain and snow to develop later in the afternoon before bands of moderate precipitation spread across the Cascades overnight. Snow levels start around 7000 ft in most areas, but lower to 4000-4500 ft after midnight.

Prepare for the elements if you head out on Sunday. Moderate to locally strong westerly ridgeline winds will keep post-frontal rain and snow showers going during the day, particularly along the west slopes of the Cascades. Snow levels hover around 3000-3500 ft. Most trailhead locations can expect 3-8” of relatively dense snow with this storm. Locally higher totals remain possible at elevations above 5000 ft, such as at Paradise. The north Cascades are not as favored by this storm as the winds circulating around the back side of the trough will be slightly weaker further north.

 

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
Friday Night Mostly clear. Temperatures remain above freezing near ridgelines and drop below freezing in valley locations. Light ridgeline winds.
Saturday Filtered sunshine gives way to obscured skies by the afternoon with light rain and snow developing. Mild with increasing light ridgeline winds.
Friday Night Mostly clear. Temperatures remain above freezing near ridgelines and drop below freezing in valley locations. Light to occasionally moderate ridgeline winds.
Saturday Mostly clear start to the day with high clouds lowering as the day progresses. Mild with increasing light to moderate ridgeline winds.
Friday Night Mostly clear. Temperatures remain above freezing near ridgelines and drop below freezing in valley locations. Light ridgeline winds.
Saturday Mostly clear start to the day with high clouds lowering as the day progresses. Mild with increasing light ridgeline winds.
Friday Night Mostly clear. Temperatures remain above freezing near ridgelines and drop below freezing in valley locations and near gaps in the Cascade Crest. Light ridgeline winds.
Saturday Filtered sunshine gives way to obscured skies by the afternoon with light rain and snow developing. Increasing light ridgeline winds.
Friday Night Mostly clear. Light ridgeline winds and light low-level E winds at the Pass will create multiple freezing levels. Temperatures will likely remain below freezing except at upper elevations where temperatures may be in the mid to upper 30s.
Saturday High clouds lower and thicken during the day. Light to occasionally moderate ridgeline and E wind at the Pass. Mild.
Friday Night Mostly clear. Light ridgeline winds and light to moderate low-level E winds at the Pass will create multiple freezing levels. Temperatures will likely remain below freezing except at upper elevations where temperatures may be in the mid to upper 30s.
Saturday High clouds lower and thicken during the day. Light to moderate ridgeline and E wind at the Pass. Mild with the inversion conditions remaining present, but weakening.
Friday Night Mostly clear. Light ridgeline winds and light low-level E winds at the Pass will create multiple freezing levels. Temperatures will likely remain well below freezing except at upper elevations where temperatures may be in the mid to upper 30s.
Saturday Mostly sunny in the morning with clouds increasing during the afternoon. Inversion conditions weaken slightly but continue to expect milder ridgeline conditions than at Pass level. Light ridgeline winds.
Friday Night Mostly clear. Gradually increasing light ridgeline winds. Temperatures will likely remain below freezing except at upper elevations where temperatures may be in the mid to upper 30s. Low-elevation stratus likely lingers in the valleys.
Saturday Filtered sunshine early, then clouds increase during the afternoon. Inversion conditions weaken slightly but continue to expect milder ridgeline conditions in valley locations. Increasing light ridgeline winds.
Friday Night Mostly clear. Light ridgeline winds. Multiple freezing levels are possible. Temperatures will likely remain below freezing except at upper elevations where temperatures may be in the mid to upper 30s. Low-elevation stratus likely lingers in the valleys.
Saturday Filtered sunshine early, then clouds increase during the afternoon. Inversion conditions weaken slightly but continue to expect milder ridgeline conditions in valley locations. Increasing light ridgeline winds.
Friday Night Mostly clear. Light to moderate ridgeline winds. Above freezing temperatures in most areas except deeper valley locations.
Saturday Filtered sunshine early, then clouds increase during the afternoon with a chance of rain and high elevation snow developing late in the day.

Precipitation (in)

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

Snow Level (ft)

Friday Evening* Friday Night* Saturday Morning* Saturday Afternoon* Saturday Evening* Saturday Night Sunday Morning Sunday Afternoon
Olympics 9500' 8500' 8000' 7000' 6500' 5000' 3500' 3000'
West North 8500' 6500' 6000' 7500' 6500' 5000' 3500' 3000'
West Central 8500' 7000' 6500' 7500' 6500' 4500' 3500' 3000'
West South 8500' 7000' 6500' 7000' 6000' 4000' 3500' 3000'
Stevens Pass 3000' 2500' 3000' 4000' 3500' 4000' 3500' 3000'
Snoqualmie Pass 3000' 2500' 3000' 5000' 4500' 4000' 3500' 3000'
East North 1000' 1000' 2000' 2500' 1000' 3500' 3500' 3500'
East Central 3000' 2500' 4000' 4000' 2500' 4000' 3500' 3500'
East South 4000' 3500' 4500' 7000' 4500' 4000' 3500' 3500'
Mt. Hood 8000' 7000' 6000' 7500' 6500' 4000' 3000' 3000'
Olympics Elevation
Friday Evening* 9500'
Friday Night* 8500'
Saturday Morning* 8000'
Saturday Afternoon* 7000'
Saturday Evening* 6500'
Saturday Night 5000'
Sunday Morning 3500'
Sunday Afternoon 3000'
West North Elevation
Friday Evening* 8500'
Friday Night* 6500'
Saturday Morning* 6000'
Saturday Afternoon* 7500'
Saturday Evening* 6500'
Saturday Night 5000'
Sunday Morning 3500'
Sunday Afternoon 3000'
West Central Elevation
Friday Evening* 8500'
Friday Night* 7000'
Saturday Morning* 6500'
Saturday Afternoon* 7500'
Saturday Evening* 6500'
Saturday Night 4500'
Sunday Morning 3500'
Sunday Afternoon 3000'
West South Elevation
Friday Evening* 8500'
Friday Night* 7000'
Saturday Morning* 6500'
Saturday Afternoon* 7000'
Saturday Evening* 6000'
Saturday Night 4000'
Sunday Morning 3500'
Sunday Afternoon 3000'
Stevens Pass Elevation
Friday Evening* 3000'
Friday Night* 2500'
Saturday Morning* 3000'
Saturday Afternoon* 4000'
Saturday Evening* 3500'
Saturday Night 4000'
Sunday Morning 3500'
Sunday Afternoon 3000'
Snoqualmie Pass Elevation
Friday Evening* 3000'
Friday Night* 2500'
Saturday Morning* 3000'
Saturday Afternoon* 5000'
Saturday Evening* 4500'
Saturday Night 4000'
Sunday Morning 3500'
Sunday Afternoon 3000'
East North Elevation
Friday Evening* 1000'
Friday Night* 1000'
Saturday Morning* 2000'
Saturday Afternoon* 2500'
Saturday Evening* 1000'
Saturday Night 3500'
Sunday Morning 3500'
Sunday Afternoon 3500'
East Central Elevation
Friday Evening* 3000'
Friday Night* 2500'
Saturday Morning* 4000'
Saturday Afternoon* 4000'
Saturday Evening* 2500'
Saturday Night 4000'
Sunday Morning 3500'
Sunday Afternoon 3500'
East South Elevation
Friday Evening* 4000'
Friday Night* 3500'
Saturday Morning* 4500'
Saturday Afternoon* 7000'
Saturday Evening* 4500'
Saturday Night 4000'
Sunday Morning 3500'
Sunday Afternoon 3500'
Mt. Hood Elevation
Friday Evening* 8000'
Friday Night* 7000'
Saturday Morning* 6000'
Saturday Afternoon* 7500'
Saturday Evening* 6500'
Saturday Night 4000'
Sunday Morning 3000'
Sunday Afternoon 3000'

5000' Temperatures (°F)

Friday Night Saturday
Max / Min Max / Min
Olympics 37 / 35 45 / 41
West North 37 / 34 40 / 36
West Central 36 / 34 41 / 37
West South 37 / 35 42 / 38
Stevens Pass 31 / 29 33 / 30
Snoqualmie Pass 34 / 32 35 / 31
East North 30 / 28 27 / 20
East Central 32 / 30 35 / 31
East South 34 / 33 37 / 32
Mt. Hood 39 / 38 41 / 35
Olympics 5000' Temperature Forecast
(Max / Min)
Friday Night 37 / 35
Saturday 45 / 41
West North 5000' Temperature Forecast
(Max / Min)
Friday Night 37 / 34
Saturday 40 / 36
West Central 5000' Temperature Forecast
(Max / Min)
Friday Night 36 / 34
Saturday 41 / 37
West South 5000' Temperature Forecast
(Max / Min)
Friday Night 37 / 35
Saturday 42 / 38
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Friday Night 31 / 29
Saturday 33 / 30
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Friday Night 34 / 32
Saturday 35 / 31
East North 5000' Temperature Forecast
(Max / Min)
Friday Night 30 / 28
Saturday 27 / 20
East Central 5000' Temperature Forecast
(Max / Min)
Friday Night 32 / 30
Saturday 35 / 31
East South 5000' Temperature Forecast
(Max / Min)
Friday Night 34 / 33
Saturday 37 / 32
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Friday Night 39 / 38
Saturday 41 / 35

Ridgeline Winds (mph)

Friday Evening Friday Night Saturday Morning Saturday Afternoon
Olympics SSW 0-10 S 0-10 S 0-10 S 5-15
West North S 5-15 SSW 5-15 SSE 5-15 S 10-20
West Central SSW 0-10 SSW 0-10 SSE 0-10 S 5-15
West South SSE 0-10 SSW 0-10 SSE 0-10 S 5-15
Stevens Pass SSE 0-10 ESE 5-15 ESE 5-15 SE 5-15
Snoqualmie Pass ESE 5-15 ESE 10-20 ESE 10-20 ESE 5-15
East North S 0-10 SE 0-10 SE 5-15 ESE 5-15
East Central SSE 0-10 S 5-15 S 5-15 S 5-15
East South SSE 0-10 S 5-15 S 5-15 S 5-15
Mt. Hood SSE 5-15 S 5-15 S 5-15 S 5-15
Olympics Ridgeline Winds (mph)
Friday Evening SSW 0-10
Friday Night S 0-10
Saturday Morning S 0-10
Saturday Afternoon S 5-15
West North Ridgeline Winds (mph)
Friday Evening S 5-15
Friday Night SSW 5-15
Saturday Morning SSE 5-15
Saturday Afternoon S 10-20
West Central Ridgeline Winds (mph)
Friday Evening SSW 0-10
Friday Night SSW 0-10
Saturday Morning SSE 0-10
Saturday Afternoon S 5-15
West South Ridgeline Winds (mph)
Friday Evening SSE 0-10
Friday Night SSW 0-10
Saturday Morning SSE 0-10
Saturday Afternoon S 5-15
Stevens Pass Ridgeline Winds (mph)
Friday Evening SSE 0-10
Friday Night ESE 5-15
Saturday Morning ESE 5-15
Saturday Afternoon SE 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Friday Evening ESE 5-15
Friday Night ESE 10-20
Saturday Morning ESE 10-20
Saturday Afternoon ESE 5-15
East North Ridgeline Winds (mph)
Friday Evening S 0-10
Friday Night SE 0-10
Saturday Morning SE 5-15
Saturday Afternoon ESE 5-15
East Central Ridgeline Winds (mph)
Friday Evening SSE 0-10
Friday Night S 5-15
Saturday Morning S 5-15
Saturday Afternoon S 5-15
East South Ridgeline Winds (mph)
Friday Evening SSE 0-10
Friday Night S 5-15
Saturday Morning S 5-15
Saturday Afternoon S 5-15
Mt. Hood Ridgeline Winds (mph)
Friday Evening SSE 5-15
Friday Night S 5-15
Saturday Morning S 5-15
Saturday Afternoon S 5-15

Extended Weather Synopsis

A ridge of high pressure rapidly rebounding offshore should bring an end to the precipitation Sunday evening. The very strong ridge moves over the Pacific Northwest, bringing unusually mild and sunny conditions. Freezing levels may rise to 11,000 or 12,000 ft west of the Cascade Crest on Monday and Tuesday afternoons, but expect inversions and colder temperatures overnight, in the morning hours, and in deep valley locations, particularly in the northern and eastern Cascades. Note the dramatic departure between the forecast conditions and the endless parade of storms we typically associate with November.

Extended Snow Level (ft)

Sunday Night Monday * Monday Night* Tuesday *
West North 2500' 5500' 8000' 9500'
Snoqualmie Pass 2500' 7000' 8000' 10000'
Mt. Hood 2500' 8000' 11500' 12000'
West North Elevation
Sunday Night 2500'
Monday * 5500'
Monday Night* 8000'
Tuesday * 9500'
Snoqualmie Pass Elevation
Sunday Night 2500'
Monday * 7000'
Monday Night* 8000'
Tuesday * 10000'
Mt. Hood Elevation
Sunday Night 2500'
Monday * 8000'
Monday Night* 11500'
Tuesday * 12000'

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

Previous forecast from Nov 16, 2023

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’.