Issued: 7:07 AM PST Sunday, January 17, 2021
by Dennis D'Amico

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

Weather Synopsis

A weak front passed through this morning producing a few inches of snow above 4000' along the west slopes of the Cascades with lesser amounts elsewhere. Scattered showers this morning will peter out by mid-day but moderate to strong WNW ridgeline winds can be expected in most zones through the afternoon. More sunshine should break out for the south Washington Cascades, Mt Hood, and east slopes of the Cascades especially further from away the Cascade crest while cloudier conditions will be found from about Snoqualmie Pass and northward. 

Strong upper-level ridging will build offshore tonight and tomorrow leaving us with dry conditions. Low clouds trapped along the west slopes of the Cascades from I-90 and north will clear out on Monday with a sunny and pleasant day expected througout the region. Northerly winds in the alpine will kick up during the day tomorrow, mainly impacting higher terrain east of the Cascade crest and Mt. Hood.  

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 Partly cloudy with isolated light rain and snow showers this morning then mostly sunny.
Sunday Night Partly to mostly clear.
Sunday Cloudy with scattered light rain and snow showers this morning then mostly cloudy with sunbreaks in the afternoon.
Sunday Night Mostly cloudy.
Sunday Cloudy with scattered light rain and snow showers this morning then mostly cloudy with sunbreaks in the afternoon.
Sunday Night Mostly cloudy.
Sunday Mostly cloudy with scattered light rain and snow showers this morning then partly to mostly sunny in the afternoon. Strong ridgeline winds.
Sunday Night Partly to mostly clear.
Sunday Cloudy with scattered light rain and snow showers this morning then mostly cloudy with sunbreaks in the afternoon. Moderate west winds.
Sunday Night Partly to mostly cloudy. Light west winds at Pass level.
Sunday Cloudy with scattered light rain and snow showers this morning then mostly cloudy with sunbreaks in the afternoon. Strong ridgeline winds. Moderate west winds at Pass level.
Sunday Night Partly to mostly cloudy. Light west winds at Pass level.
Sunday Mostly cloudy with scattered light rain and snow showers this morning then partly to mostly sunny in the afternoon. Strong ridgeline winds.
Sunday Night Partly to mostly clear.
Sunday Mostly cloudy with isolated light rain and snow showers this morning then mostly sunny in the afternoon. Strong ridgeline winds.
Sunday Night Mostly clear.
Sunday Mostly cloudy with isolated light rain and snow showers this morning then mostly sunny in the afternoon. Strong ridgeline winds.
Sunday Night Mostly clear.
Sunday Mostly cloudy with scattered light rain and snow showers this morning then partly to mostly sunny in the afternoon with periods of high clouds. Strong winds.
Sunday Night Mostly clear.

Precipitation (in)

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

Snow Level (ft)

Sunday Morning Sunday Afternoon Sunday Evening Sunday Night Monday Morning Monday Afternoon
Olympics 4500' 4500' 4500' 4000' 4500' 6000'
West North 3500' 3000' 2500' 2500' 3500' 4500'
West Central 3500' 3500' 2500' 2500' 3500' 5000'
West South 4500' 4500' 2500' 2500' 4000' 6000'
Stevens Pass 3500' 3500' 2500' 2500' 3500' 4500'
Snoqualmie Pass 4000' 3500' 2500' 2500' 3500' 4500'
East North 4000' 4000' 2000' 2000' 2500' 3500'
East Central 4500' 4000' 3000' 2500' 3500' 4500'
East South 4500' 5500' 3500' 3500' 4000' 4500'
Mt. Hood 5500' 7000' 7000' 7000' 5500' 5000'
Olympics Elevation
Sunday Morning 4500'
Sunday Afternoon 4500'
Sunday Evening 4500'
Sunday Night 4000'
Monday Morning 4500'
Monday Afternoon 6000'
West North Elevation
Sunday Morning 3500'
Sunday Afternoon 3000'
Sunday Evening 2500'
Sunday Night 2500'
Monday Morning 3500'
Monday Afternoon 4500'
West Central Elevation
Sunday Morning 3500'
Sunday Afternoon 3500'
Sunday Evening 2500'
Sunday Night 2500'
Monday Morning 3500'
Monday Afternoon 5000'
West South Elevation
Sunday Morning 4500'
Sunday Afternoon 4500'
Sunday Evening 2500'
Sunday Night 2500'
Monday Morning 4000'
Monday Afternoon 6000'
Stevens Pass Elevation
Sunday Morning 3500'
Sunday Afternoon 3500'
Sunday Evening 2500'
Sunday Night 2500'
Monday Morning 3500'
Monday Afternoon 4500'
Snoqualmie Pass Elevation
Sunday Morning 4000'
Sunday Afternoon 3500'
Sunday Evening 2500'
Sunday Night 2500'
Monday Morning 3500'
Monday Afternoon 4500'
East North Elevation
Sunday Morning 4000'
Sunday Afternoon 4000'
Sunday Evening 2000'
Sunday Night 2000'
Monday Morning 2500'
Monday Afternoon 3500'
East Central Elevation
Sunday Morning 4500'
Sunday Afternoon 4000'
Sunday Evening 3000'
Sunday Night 2500'
Monday Morning 3500'
Monday Afternoon 4500'
East South Elevation
Sunday Morning 4500'
Sunday Afternoon 5500'
Sunday Evening 3500'
Sunday Night 3500'
Monday Morning 4000'
Monday Afternoon 4500'
Mt. Hood Elevation
Sunday Morning 5500'
Sunday Afternoon 7000'
Sunday Evening 7000'
Sunday Night 7000'
Monday Morning 5500'
Monday Afternoon 5000'

5000' Temperatures (°F)

Sunday Sunday Night
Max / Min Max / Min
Olympics 31 / 27 25 / 23
West North 29 / 27 25 / 20
West Central 29 / 28 27 / 20
West South 32 / 29 27 / 23
Stevens Pass 29 / 28 27 / 23
Snoqualmie Pass 30 / 28 27 / 22
East North 30 / 27 26 / 21
East Central 31 / 27 26 / 23
East South 33 / 29 27 / 25
Mt. Hood 35 / 31 31 / 28
Olympics 5000' Temperature Forecast
(Max / Min)
Sunday 31 / 27
Sunday Night 25 / 23
West North 5000' Temperature Forecast
(Max / Min)
Sunday 29 / 27
Sunday Night 25 / 20
West Central 5000' Temperature Forecast
(Max / Min)
Sunday 29 / 28
Sunday Night 27 / 20
West South 5000' Temperature Forecast
(Max / Min)
Sunday 32 / 29
Sunday Night 27 / 23
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Sunday 29 / 28
Sunday Night 27 / 23
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Sunday 30 / 28
Sunday Night 27 / 22
East North 5000' Temperature Forecast
(Max / Min)
Sunday 30 / 27
Sunday Night 26 / 21
East Central 5000' Temperature Forecast
(Max / Min)
Sunday 31 / 27
Sunday Night 26 / 23
East South 5000' Temperature Forecast
(Max / Min)
Sunday 33 / 29
Sunday Night 27 / 25
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Sunday 35 / 31
Sunday Night 31 / 28

Ridgeline Winds (mph)

Sunday Morning Sunday Afternoon Sunday Evening Sunday Night
Olympics WNW 15-25 NW 5-15 NW 5-15 NNW 5-15
West North W 10-20 WNW 5-15 W 0-10 WNW 0-10
West Central W 15-25 NW 15-25 NW 10-20 WNW 10-20
West South WNW 20-30 NW 15-25 NNW 15-25 NNW 10-20
Stevens Pass WNW 15-25 NW 10-20 WNW 10-20 NW 5-15
Snoqualmie Pass WNW 20-30 NW 15-25 NW 15-25 NW 10-20
East North WNW 25-35 WNW 20-30 NW 10-20 NW 10-20
East Central WNW 30-40 WNW 20-30 NW 15-25 NW 10-20
East South WNW 20-30 NW 15-25 NW 10-20 NNW 10-20
Mt. Hood WNW 25-35 NW 20-30 NNW 10-20 NNW 10-20
Olympics Ridgeline Winds (mph)
Sunday Morning WNW 15-25
Sunday Afternoon NW 5-15
Sunday Evening NW 5-15
Sunday Night NNW 5-15
West North Ridgeline Winds (mph)
Sunday Morning W 10-20
Sunday Afternoon WNW 5-15
Sunday Evening W 0-10
Sunday Night WNW 0-10
West Central Ridgeline Winds (mph)
Sunday Morning W 15-25
Sunday Afternoon NW 15-25
Sunday Evening NW 10-20
Sunday Night WNW 10-20
West South Ridgeline Winds (mph)
Sunday Morning WNW 20-30
Sunday Afternoon NW 15-25
Sunday Evening NNW 15-25
Sunday Night NNW 10-20
Stevens Pass Ridgeline Winds (mph)
Sunday Morning WNW 15-25
Sunday Afternoon NW 10-20
Sunday Evening WNW 10-20
Sunday Night NW 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Sunday Morning WNW 20-30
Sunday Afternoon NW 15-25
Sunday Evening NW 15-25
Sunday Night NW 10-20
East North Ridgeline Winds (mph)
Sunday Morning WNW 25-35
Sunday Afternoon WNW 20-30
Sunday Evening NW 10-20
Sunday Night NW 10-20
East Central Ridgeline Winds (mph)
Sunday Morning WNW 30-40
Sunday Afternoon WNW 20-30
Sunday Evening NW 15-25
Sunday Night NW 10-20
East South Ridgeline Winds (mph)
Sunday Morning WNW 20-30
Sunday Afternoon NW 15-25
Sunday Evening NW 10-20
Sunday Night NNW 10-20
Mt. Hood Ridgeline Winds (mph)
Sunday Morning WNW 25-35
Sunday Afternoon NW 20-30
Sunday Evening NNW 10-20
Sunday Night NNW 10-20

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

Previous forecast from Jan 16, 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’.