Issued: 2:00 PM PST Monday, January 25, 2021
by Dennis D'Amico

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

Weather Synopsis

Scattered showers associated with a cold upper level trough that's positioned along the coast will fade quickly with the loss of daytime heating this evening. Cloud cover should diminish overnight as well.

An occluded front will rotate north towards our area on Tuesday but won't reach us until Tuesday night. This frontal boundary will extend from an upper low complex digging well of the California coast. While we wait for the frontal boundary to arrive, look for increasing offshore flow and easterly winds Tuesday afternoon. Strong SE winds will extend up to the Cascade crest level and affect a large swath of the south and central Cascades. Very light upslope snow and low clouds should develop along the east slopes of the Cascades during the day on Tuesday as well.

SE winds will land in the strong to even extreme category Tuesday evening as the occluded front lifts from south to north.This front should bring light to moderate snow to the east slopes of the Cascades with light amounts on the west side as the front stretches and weakens. A trailing shortwave feature should rotate north in a similar fashion during the day on Wednesday, providing a secondary burst of light snow along the east slopes. Scattered showers are likely along the west slopes. 

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 Partly cloudy in the evening becoming mostly cloudy after midnight.
Tuesday Mostly cloudy. Periods of filtered sunshine.
Monday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy after midnight.
Tuesday Partly cloudy. Periods of filtered sunshine.
Monday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy after midnight.
Tuesday Mostly cloudy in the morning with sunbreaks then cloudy in the afternoon. SE ridgeline winds becoming very strong in the afternoon.
Monday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy after midnight.
Tuesday Mostly cloudy in the morning with sunbreaks then cloudy in the afternoon. E-SE Pass level and ridgeline winds becoming strong in the afternoon.
Monday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy after midnight. Light east winds at Pass level.
Tuesday Mostly cloudy in the morning with sunbreaks then cloudy in the afternoon. E-SE Pass level and ridgeline winds becoming moderate to strong in the afternoon.
Monday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy after midnight. Light east winds at Pass level.
Tuesday Mostly cloudy in the morning with sunbreaks then cloudy in the afternoon. SE ridgeline winds becoming strong in the afternoon. Moderate east winds at Pass level becoming strong in the afternoon.
Monday Night Partly cloudy.
Tuesday Becoming cloudy in the morning with very light snow developing.
Monday Night Partly cloudy in the evening, becoming cloudy eastern foothills.
Tuesday Becoming cloudy in the morning with very light snow developing.
Monday Night Partly cloudy in the evening, becoming cloudy eastern foothills.
Tuesday Becoming cloudy in the morning with very light snow developing.
Monday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy after midnight.
Tuesday Partly cloudy in the morning. Becoming cloudy in the afternoon with a chance of light snow. SE ridgeline winds becoming strong in the afternoon.

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

Snow Level (ft)

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

5000' Temperatures (°F)

Monday Night Tuesday
Max / Min Max / Min
Olympics 16 / 12 22 / 13
West North 17 / 14 20 / 14
West Central 18 / 12 18 / 10
West South 18 / 13 21 / 15
Stevens Pass 16 / 11 18 / 10
Snoqualmie Pass 17 / 11 17 / 12
East North 14 / 8 15 / 9
East Central 16 / 12 16 / 10
East South 16 / 11 16 / 12
Mt. Hood 18 / 14 21 / 13
Olympics 5000' Temperature Forecast
(Max / Min)
Monday Night 16 / 12
Tuesday 22 / 13
West North 5000' Temperature Forecast
(Max / Min)
Monday Night 17 / 14
Tuesday 20 / 14
West Central 5000' Temperature Forecast
(Max / Min)
Monday Night 18 / 12
Tuesday 18 / 10
West South 5000' Temperature Forecast
(Max / Min)
Monday Night 18 / 13
Tuesday 21 / 15
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 16 / 11
Tuesday 18 / 10
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 17 / 11
Tuesday 17 / 12
East North 5000' Temperature Forecast
(Max / Min)
Monday Night 14 / 8
Tuesday 15 / 9
East Central 5000' Temperature Forecast
(Max / Min)
Monday Night 16 / 12
Tuesday 16 / 10
East South 5000' Temperature Forecast
(Max / Min)
Monday Night 16 / 11
Tuesday 16 / 12
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday Night 18 / 14
Tuesday 21 / 13

Ridgeline Winds (mph)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon
Olympics SW 0-10 SSW 5-15 S 10-20 SE 15-25
West North S 5-15 S 10-20 S 10-20 SE 10-20
West Central SSW 5-15 S 5-15 S 10-20 SE 25-35
West South SW 0-10 SSW 5-15 SSE 10-20 SE 25-35
Stevens Pass W 0-10 SE 0-10 SE 5-15 SE 20-30
Snoqualmie Pass W 0-10 SE 0-10 SE 10-20 SE 25-35
East North SW 0-10 SW 5-15 SSE 5-15 SSE 10-20
East Central W 0-10 SSE 5-15 SSE 5-15 SE 15-25
East South W 0-10 S 5-15 SSE 5-15 SE 10-20
Mt. Hood W 0-10 SW 5-15 S 5-15 SE 20-30
Olympics Ridgeline Winds (mph)
Monday Evening SW 0-10
Monday Night SSW 5-15
Tuesday Morning S 10-20
Tuesday Afternoon SE 15-25
West North Ridgeline Winds (mph)
Monday Evening S 5-15
Monday Night S 10-20
Tuesday Morning S 10-20
Tuesday Afternoon SE 10-20
West Central Ridgeline Winds (mph)
Monday Evening SSW 5-15
Monday Night S 5-15
Tuesday Morning S 10-20
Tuesday Afternoon SE 25-35
West South Ridgeline Winds (mph)
Monday Evening SW 0-10
Monday Night SSW 5-15
Tuesday Morning SSE 10-20
Tuesday Afternoon SE 25-35
Stevens Pass Ridgeline Winds (mph)
Monday Evening W 0-10
Monday Night SE 0-10
Tuesday Morning SE 5-15
Tuesday Afternoon SE 20-30
Snoqualmie Pass Ridgeline Winds (mph)
Monday Evening W 0-10
Monday Night SE 0-10
Tuesday Morning SE 10-20
Tuesday Afternoon SE 25-35
East North Ridgeline Winds (mph)
Monday Evening SW 0-10
Monday Night SW 5-15
Tuesday Morning SSE 5-15
Tuesday Afternoon SSE 10-20
East Central Ridgeline Winds (mph)
Monday Evening W 0-10
Monday Night SSE 5-15
Tuesday Morning SSE 5-15
Tuesday Afternoon SE 15-25
East South Ridgeline Winds (mph)
Monday Evening W 0-10
Monday Night S 5-15
Tuesday Morning SSE 5-15
Tuesday Afternoon SE 10-20
Mt. Hood Ridgeline Winds (mph)
Monday Evening W 0-10
Monday Night SW 5-15
Tuesday Morning S 5-15
Tuesday Afternoon SE 20-30

Extended Weather Synopsis

General cool upper level troughing will stay anchored offshore Thursday and Friday. There aren't any organized systems but scattered showers will stay in each 12 hr forecast period. Temperatures and freezing levels will remain on the cooler side through the extended. We may see more organized frontal systems arrive over the weekend. 

Extended Snow Level (ft)

Wednesday Night Thursday Thursday Night Friday
West North 500' 2500' 500' 2000'
Snoqualmie Pass 1000' 2500' 500' 2000'
Mt. Hood 1500' 2500' 1000' 2000'
West North Elevation
Wednesday Night 500'
Thursday 2500'
Thursday Night 500'
Friday 2000'
Snoqualmie Pass Elevation
Wednesday Night 1000'
Thursday 2500'
Thursday Night 500'
Friday 2000'
Mt. Hood Elevation
Wednesday Night 1500'
Thursday 2500'
Thursday Night 1000'
Friday 2000'

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

Previous forecast from Jan 25, 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’.