Issued: 2:01 PM PST Tuesday, November 19, 2024
by Dennis D'Amico

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

Weather Synopsis

An exceptionally deep low pressure system positioned well offshore will bring windy conditions and locally heavy snowfall our mountains tonight through Wednesday morning. Warm frontal precipitation will lift from SW to NE tonight over the area. The heaviest precipitation will occur along the east slopes of the Cascades (and Olympics) thanks to some upsloping and closer to the Washington/Oregon border where the axis of heaviest precipitation will be aimed. Portions of the east slopes of the Cascades south of I-90 and near Mt Hood may exceed 1' of snow overnight. Precipitation will be lighter in the Passes and northwest and northcentral Cascades.  The cold front will stall along the Olympics and weaken as it washes out during the day.  The heaviest showers will linger over the Olympic peninsula with lighter showers elsewhere. 

The wind will be the other major story with strong to extreme winds in many areas starting late this afternoon through Wednesday morning.  E-SE winds will be the strongest near and west of the Cascade crest with those extreme southeasterlies reaching into the western Cascade foothills. Even for areas that aren't receiving heavy snow, the combination of snow and winds will severely impact visibility. 

We'll be inbetween the stronger jet stream over northern CA and the upper low still positioned a bit farther offshore Wednesday night and Thursday.  We won't completely dry out but showers and winds will be much lighter.  Snow levels will moderate a bit on Thursday as well into the 3000-4000' range. 

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
Tuesday Night Light to moderate rain and snow, heaviest E/SE slopes of the Olympics. Extreme winds.
Wednesday Light to occasionally moderate rain and snow showers, heaviest south slopes of the Olympics.
Tuesday Night Light to occasionally moderate rain and snow developing this evening. Strong winds.
Wednesday Light to occasionally moderate rain and snow becoming scattered rain and snow showers in the afternoon.
Tuesday Night Light to occasionally moderate rain and snow developing this evening. Strong to extreme winds.
Wednesday Light to occasionally moderate rain and snow becoming scattered rain and snow showers in the afternoon. Strong winds decreasing during the morning.
Tuesday Night Light to moderate rain and snow developing this evening. Strong to extreme winds.
Wednesday Light to occasionally moderate rain and snow becoming scattered rain and snow showers in the afternoon. Strong winds decreasing during the morning.
Tuesday Night Light snow developing this evening. Strong to extreme E-SE winds at ridgeline and Pass level.
Wednesday Light snow becoming scattered showers in the afternoon. Strong E-SE ridgeline and Pass level winds decreasing during the morning.
Tuesday Night Light snow developing this evening. Strong to extreme E-SE winds at ridgeline and Pass level.
Wednesday Light snow becoming scattered showers in the afternoon. Strong E-SE ridgeline and Pass level winds decreasing during the morning.
Tuesday Night Light to occasionally moderate snow developing later this evening. Strong winds.
Wednesday Light to moderate snow in the morning, becoming light rain and snow showers in the afternoon. Strong winds decreasing in the morning.
Tuesday Night Light to moderate snow developing later this evening. Strong winds.
Wednesday Light to moderate snow in the morning, becoming light rain and snow showers in the afternoon. Strong winds decreasing in the morning.
Tuesday Night Moderate snow developing later this evening. Strong winds.
Wednesday Light to moderate snow in the morning, becoming light rain and snow showers in the afternoon. Strong winds decreasing in the morning.
Tuesday Night Moderate rain and snow developing later this evening. Strong to extreme winds.
Wednesday Moderate rain and snow in the morning, becoming light to occasionally moderate snow showers in the afternoon. Strong winds decreasing in the morning.

Issued: 2:01 PM PST Tuesday, November 19, 2024

Precipitation (in)

Tuesday Night Wednesday Wednesday Night Thursday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0.25 - 0.50 0.50 LT 0.25 LT 0.10
Mt Baker Ski Area 0.50 0.25 - 0.50 0.25 LT 0.10
Mt. Loop - Barlow Pass 0.25 LT 0.25 LT 0.25 LT 0.10
Stevens Pass 0.25 LT 0.25 LT 0.10 LT 0.10
Snoqualmie Pass 0.25 LT 0.25 LT 0.10 LT 0.10
Crystal Mt 0.50 - 0.75 0.25 LT 0.10 LT 0.10
Paradise 0.50 - 0.75 0.25 - 0.50 LT 0.25 LT 0.10
White Pass 0.50 - 0.75 LT 0.25 LT 0.10 LT 0.10
Washington Pass 0.50 LT 0.25 LT 0.10 LT 0.10
Mission Ridge 0.50 - 0.75 0.25 LT 0.10 LT 0.10
Salmon la Sac - Gallagher Head 0.75 0.25 LT 0.25 LT 0.10
Tieton River - Darland Mt. 1.00 - 1.50 0.25 LT 0.10 LT 0.25
Mt Hood Meadows 1.00 - 1.50 0.25 - 0.50 LT 0.25 LT 0.25
Timberline 1.00 - 1.50 0.25 LT 0.25 LT 0.25
Hurricane Ridge Precipitation (in)
Tuesday Night 0.25 - 0.50
Wednesday 0.50
Wednesday Night LT 0.25
Thursday LT 0.10
Mt Baker Ski Area Precipitation (in)
Tuesday Night 0.50
Wednesday 0.25 - 0.50
Wednesday Night 0.25
Thursday LT 0.10
Mt. Loop - Barlow Pass Precipitation (in)
Tuesday Night 0.25
Wednesday LT 0.25
Wednesday Night LT 0.25
Thursday LT 0.10
Stevens Pass Precipitation (in)
Tuesday Night 0.25
Wednesday LT 0.25
Wednesday Night LT 0.10
Thursday LT 0.10
Snoqualmie Pass Precipitation (in)
Tuesday Night 0.25
Wednesday LT 0.25
Wednesday Night LT 0.10
Thursday LT 0.10
Crystal Mt Precipitation (in)
Tuesday Night 0.50 - 0.75
Wednesday 0.25
Wednesday Night LT 0.10
Thursday LT 0.10
Paradise Precipitation (in)
Tuesday Night 0.50 - 0.75
Wednesday 0.25 - 0.50
Wednesday Night LT 0.25
Thursday LT 0.10
White Pass Precipitation (in)
Tuesday Night 0.50 - 0.75
Wednesday LT 0.25
Wednesday Night LT 0.10
Thursday LT 0.10
Washington Pass Precipitation (in)
Tuesday Night 0.50
Wednesday LT 0.25
Wednesday Night LT 0.10
Thursday LT 0.10
Mission Ridge Precipitation (in)
Tuesday Night 0.50 - 0.75
Wednesday 0.25
Wednesday Night LT 0.10
Thursday LT 0.10
Salmon la Sac - Gallagher Head Precipitation (in)
Tuesday Night 0.75
Wednesday 0.25
Wednesday Night LT 0.25
Thursday LT 0.10
Tieton River - Darland Mt. Precipitation (in)
Tuesday Night 1.00 - 1.50
Wednesday 0.25
Wednesday Night LT 0.10
Thursday LT 0.25
Mt Hood Meadows Precipitation (in)
Tuesday Night 1.00 - 1.50
Wednesday 0.25 - 0.50
Wednesday Night LT 0.25
Thursday LT 0.25
Timberline Precipitation (in)
Tuesday Night 1.00 - 1.50
Wednesday 0.25
Wednesday Night LT 0.25
Thursday LT 0.25

Issued: 2:01 PM PST Tuesday, November 19, 2024

Snow Level (ft)

Tuesday Evening* Tuesday Night* Wednesday Morning* Wednesday Afternoon* Wednesday Evening* Wednesday Night* Thursday Morning* Thursday Afternoon*
Olympics 2000' 2500' 3000' 3500' 3000' 3000' 3500' 4500'
West North 1500' 1500' 1500' 3500' 3000' 2500' 3000' 4000'
West Central 1500' 1500' 1500' 3500' 3000' 2000' 3000' 4000'
West South 1500' 1500' 1500' 4000' 3000' 2000' 3000' 4500'
Stevens Pass 1000' 1000' 1000' 3000' 2500' 1500' 2500' 3500'
Snoqualmie Pass 1500' 1000' 1500' 3000' 2500' 2000' 2500' 3500'
East North 1000' 1000' 1000' 2500' 2000' 1000' 1500' 2000'
East Central 1000' 1000' 1000' 2500' 2000' 1500' 2000' 2500'
East South 1000' 1000' 1000' 3000' 2500' 1500' 2500' 4000'
Mt. Hood 3000' 3500' 4000' 4500' 4000' 4000' 4000' 4000'
Olympics Elevation
Tuesday Evening* 2000'
Tuesday Night* 2500'
Wednesday Morning* 3000'
Wednesday Afternoon* 3500'
Wednesday Evening* 3000'
Wednesday Night* 3000'
Thursday Morning* 3500'
Thursday Afternoon* 4500'
West North Elevation
Tuesday Evening* 1500'
Tuesday Night* 1500'
Wednesday Morning* 1500'
Wednesday Afternoon* 3500'
Wednesday Evening* 3000'
Wednesday Night* 2500'
Thursday Morning* 3000'
Thursday Afternoon* 4000'
West Central Elevation
Tuesday Evening* 1500'
Tuesday Night* 1500'
Wednesday Morning* 1500'
Wednesday Afternoon* 3500'
Wednesday Evening* 3000'
Wednesday Night* 2000'
Thursday Morning* 3000'
Thursday Afternoon* 4000'
West South Elevation
Tuesday Evening* 1500'
Tuesday Night* 1500'
Wednesday Morning* 1500'
Wednesday Afternoon* 4000'
Wednesday Evening* 3000'
Wednesday Night* 2000'
Thursday Morning* 3000'
Thursday Afternoon* 4500'
Stevens Pass Elevation
Tuesday Evening* 1000'
Tuesday Night* 1000'
Wednesday Morning* 1000'
Wednesday Afternoon* 3000'
Wednesday Evening* 2500'
Wednesday Night* 1500'
Thursday Morning* 2500'
Thursday Afternoon* 3500'
Snoqualmie Pass Elevation
Tuesday Evening* 1500'
Tuesday Night* 1000'
Wednesday Morning* 1500'
Wednesday Afternoon* 3000'
Wednesday Evening* 2500'
Wednesday Night* 2000'
Thursday Morning* 2500'
Thursday Afternoon* 3500'
East North Elevation
Tuesday Evening* 1000'
Tuesday Night* 1000'
Wednesday Morning* 1000'
Wednesday Afternoon* 2500'
Wednesday Evening* 2000'
Wednesday Night* 1000'
Thursday Morning* 1500'
Thursday Afternoon* 2000'
East Central Elevation
Tuesday Evening* 1000'
Tuesday Night* 1000'
Wednesday Morning* 1000'
Wednesday Afternoon* 2500'
Wednesday Evening* 2000'
Wednesday Night* 1500'
Thursday Morning* 2000'
Thursday Afternoon* 2500'
East South Elevation
Tuesday Evening* 1000'
Tuesday Night* 1000'
Wednesday Morning* 1000'
Wednesday Afternoon* 3000'
Wednesday Evening* 2500'
Wednesday Night* 1500'
Thursday Morning* 2500'
Thursday Afternoon* 4000'
Mt. Hood Elevation
Tuesday Evening* 3000'
Tuesday Night* 3500'
Wednesday Morning* 4000'
Wednesday Afternoon* 4500'
Wednesday Evening* 4000'
Wednesday Night* 4000'
Thursday Morning* 4000'
Thursday Afternoon* 4000'

Issued: 2:01 PM PST Tuesday, November 19, 2024

5000' Temperatures (°F)

Tuesday Night Wednesday
Max / Min Max / Min
Olympics 28 / 25 27 / 26
West North 25 / 23 29 / 24
West Central 23 / 21 30 / 23
West South 27 / 23 30 / 26
Stevens Pass 25 / 21 30 / 24
Snoqualmie Pass 24 / 22 30 / 25
East North 20 / 19 27 / 20
East Central 25 / 21 29 / 25
East South 25 / 21 30 / 26
Mt. Hood 30 / 27 32 / 29
Olympics 5000' Temperature Forecast
(Max / Min)
Tuesday Night 28 / 25
Wednesday 27 / 26
West North 5000' Temperature Forecast
(Max / Min)
Tuesday Night 25 / 23
Wednesday 29 / 24
West Central 5000' Temperature Forecast
(Max / Min)
Tuesday Night 23 / 21
Wednesday 30 / 23
West South 5000' Temperature Forecast
(Max / Min)
Tuesday Night 27 / 23
Wednesday 30 / 26
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Tuesday Night 25 / 21
Wednesday 30 / 24
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Tuesday Night 24 / 22
Wednesday 30 / 25
East North 5000' Temperature Forecast
(Max / Min)
Tuesday Night 20 / 19
Wednesday 27 / 20
East Central 5000' Temperature Forecast
(Max / Min)
Tuesday Night 25 / 21
Wednesday 29 / 25
East South 5000' Temperature Forecast
(Max / Min)
Tuesday Night 25 / 21
Wednesday 30 / 26
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Tuesday Night 30 / 27
Wednesday 32 / 29

Issued: 2:01 PM PST Tuesday, November 19, 2024

Ridgeline Winds (mph)

Tuesday Evening Tuesday Night Wednesday Morning Wednesday Afternoon
Olympics SSE 35-50 S 30-40 S 15-25 SSW 5-15
West North SE 20-30 SE 15-25 SSE 5-15 S 10-20
West Central ESE 30-40 SE 20-30 ESE 5-15 SSE 5-15
West South SE 35-50 SSE 15-25 SE 5-15 SW 5-15
Stevens Pass ESE 30-40 ESE 20-30 SSE 10-20 SSE 5-15
Snoqualmie Pass ESE 35-50 SE 30-40 SE 10-20 SE 10-20
East North ESE 25-35 ESE 25-35 SE 10-20 SSE 5-15
East Central ESE 25-35 SE 20-30 SSE 10-20 S 15-25
East South ESE 20-30 SSE 20-30 S 10-20 SSW 5-15
Mt. Hood SSE 30-40 S 30-40 SSW 10-20 SSW 15-25
Olympics Ridgeline Winds (mph)
Tuesday Evening SSE 35-50
Tuesday Night S 30-40
Wednesday Morning S 15-25
Wednesday Afternoon SSW 5-15
West North Ridgeline Winds (mph)
Tuesday Evening SE 20-30
Tuesday Night SE 15-25
Wednesday Morning SSE 5-15
Wednesday Afternoon S 10-20
West Central Ridgeline Winds (mph)
Tuesday Evening ESE 30-40
Tuesday Night SE 20-30
Wednesday Morning ESE 5-15
Wednesday Afternoon SSE 5-15
West South Ridgeline Winds (mph)
Tuesday Evening SE 35-50
Tuesday Night SSE 15-25
Wednesday Morning SE 5-15
Wednesday Afternoon SW 5-15
Stevens Pass Ridgeline Winds (mph)
Tuesday Evening ESE 30-40
Tuesday Night ESE 20-30
Wednesday Morning SSE 10-20
Wednesday Afternoon SSE 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Tuesday Evening ESE 35-50
Tuesday Night SE 30-40
Wednesday Morning SE 10-20
Wednesday Afternoon SE 10-20
East North Ridgeline Winds (mph)
Tuesday Evening ESE 25-35
Tuesday Night ESE 25-35
Wednesday Morning SE 10-20
Wednesday Afternoon SSE 5-15
East Central Ridgeline Winds (mph)
Tuesday Evening ESE 25-35
Tuesday Night SE 20-30
Wednesday Morning SSE 10-20
Wednesday Afternoon S 15-25
East South Ridgeline Winds (mph)
Tuesday Evening ESE 20-30
Tuesday Night SSE 20-30
Wednesday Morning S 10-20
Wednesday Afternoon SSW 5-15
Mt. Hood Ridgeline Winds (mph)
Tuesday Evening SSE 30-40
Tuesday Night S 30-40
Wednesday Morning SSW 10-20
Wednesday Afternoon SSW 15-25

Issued: 2:01 PM PST Tuesday, November 19, 2024

Extended Weather Synopsis

Another frontal system will approach form the south Thursday night and Friday.  This system could be messing with a warming trend leading to mixed precipitation types (freezing rain) for the Passes and the central/south WA Cascades, or it could just be a milder storm with snow levels pushing above 5-7000'.  A more low key and light showery pattern looks likely for Saturday with snow levels pegged between 3000-4000'. 

Extended Snow Level (ft)

Thursday Night* Friday * Friday Night* Saturday *
West North 3500' 4000' 3500' 3500'
Snoqualmie Pass 3000' 4000' 3500' 3500'
Mt. Hood 7000' 4500' 4000' 4000'
West North Elevation
Thursday Night* 3500'
Friday * 4000'
Friday Night* 3500'
Saturday * 3500'
Snoqualmie Pass Elevation
Thursday Night* 3000'
Friday * 4000'
Friday Night* 3500'
Saturday * 3500'
Mt. Hood Elevation
Thursday Night* 7000'
Friday * 4500'
Friday Night* 4000'
Saturday * 4000'

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

Previous forecast from Nov 18, 2024

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’.