Issued: 7:15 AM PST Sunday, January 3, 2021
by Robert Hahn

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

Weather Synopsis

Saturday night's strong frontal passage ushered in significantly colder air and a relative break amidst an unrelenting storm cycle. Temperatures are generally in the 20's and low 30's at NWAC stations on Sunday morning. A trough with an embedded shortwave feature should bring light to moderate snow showers to the region today.

Another storm develops off the Oregon coast, lifting a warm front over our region Sunday night with rising snow levels, ESE flow, and increasing moderate to heavy rain and snow. E flow is likely to keep Snoqualmie Pass as Snow until 7-10 AM on Monday morning. The system is progressive with the cold front moving through during the mid-day hours on Monday. This should bring the heaviest precipitation to the region Monday morning. Snow levels should drop behind the front and we're expecting moderate to strong convergence to develop late in the day somewhere in the central Cascades. Many regions of the Cascades can expect 6-18" of snowfall out of this event, with significant spillover onto the east slopes of the Cascades.

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 Light snow showers.
Sunday Night Cloudy in the evening with moderate rain and snow developing overnight.
Sunday Light to moderate snow showers.
Sunday Night Cloudy in the evening with moderate then heavy rain and snow developing after midnight.
Sunday Light to moderate snow showers.
Sunday Night Cloudy in the evening with moderate then heavy rain and snow developing after midnight.
Sunday Light snow showers.
Sunday Night Cloudy in the evening with moderate then heavy rain and snow developing overnight.
Sunday Light to occasionally moderate snow showers. Light W winds at pass level.
Sunday Night Cloudy in the evening with moderate rain and snow developing after midnight. Light E winds at pass level.
Sunday Light to moderate snow showers. Light W winds at pass level.
Sunday Night Cloudy in the evening with moderate rain and snow developing after midnight. Light E winds at pass level becoming moderate overnight.
Sunday Light to occasionally moderate snow showers.
Sunday Night Cloudy in the evening with light to moderate snow developing after midnight.
Sunday Light to occasionally moderate snow showers.
Sunday Night Cloudy in the evening with moderate snow developing after midnight.
Sunday Light snow showers near the Cascade Crest.
Sunday Night Cloudy in the evening with moderate rain and snow developing overnight.
Sunday Light snow showers in the morning, then partly cloudy in the afternoon.
Sunday Night Moderate to heavy rain and snow. Strong wind gusts in the alpine.

Issued: 7:15 AM PST Sunday, January 3, 2021

Precipitation (in)

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

Issued: 7:15 AM PST Sunday, January 3, 2021

Snow Level (ft)

Sunday Morning Sunday Afternoon Sunday Evening* Sunday Night* Monday Morning* Monday Afternoon
Olympics 2500' 3000' 3000' 4500' 4500' 3500'
West North 1500' 2000' 2500' 2000' 2500' 3000'
West Central 2000' 2500' 2500' 3000' 3000' 3000'
West South 2000' 3000' 3000' 3500' 4500' 4000'
Stevens Pass 2000' 2500' 2500' 2500' 2500' 3000'
Snoqualmie Pass 2000' 2500' 3000' 3000' 3500' 3500'
East North 1500' 2500' 2000' 2000' 2500' 3000'
East Central 2500' 2500' 2500' 3000' 3000' 3500'
East South 2500' 3000' 3000' 4000' 4500' 4000'
Mt. Hood 3500' 3500' 5000' 5000' 5500' 4500'
Olympics Elevation
Sunday Morning 2500'
Sunday Afternoon 3000'
Sunday Evening* 3000'
Sunday Night* 4500'
Monday Morning* 4500'
Monday Afternoon 3500'
West North Elevation
Sunday Morning 1500'
Sunday Afternoon 2000'
Sunday Evening* 2500'
Sunday Night* 2000'
Monday Morning* 2500'
Monday Afternoon 3000'
West Central Elevation
Sunday Morning 2000'
Sunday Afternoon 2500'
Sunday Evening* 2500'
Sunday Night* 3000'
Monday Morning* 3000'
Monday Afternoon 3000'
West South Elevation
Sunday Morning 2000'
Sunday Afternoon 3000'
Sunday Evening* 3000'
Sunday Night* 3500'
Monday Morning* 4500'
Monday Afternoon 4000'
Stevens Pass Elevation
Sunday Morning 2000'
Sunday Afternoon 2500'
Sunday Evening* 2500'
Sunday Night* 2500'
Monday Morning* 2500'
Monday Afternoon 3000'
Snoqualmie Pass Elevation
Sunday Morning 2000'
Sunday Afternoon 2500'
Sunday Evening* 3000'
Sunday Night* 3000'
Monday Morning* 3500'
Monday Afternoon 3500'
East North Elevation
Sunday Morning 1500'
Sunday Afternoon 2500'
Sunday Evening* 2000'
Sunday Night* 2000'
Monday Morning* 2500'
Monday Afternoon 3000'
East Central Elevation
Sunday Morning 2500'
Sunday Afternoon 2500'
Sunday Evening* 2500'
Sunday Night* 3000'
Monday Morning* 3000'
Monday Afternoon 3500'
East South Elevation
Sunday Morning 2500'
Sunday Afternoon 3000'
Sunday Evening* 3000'
Sunday Night* 4000'
Monday Morning* 4500'
Monday Afternoon 4000'
Mt. Hood Elevation
Sunday Morning 3500'
Sunday Afternoon 3500'
Sunday Evening* 5000'
Sunday Night* 5000'
Monday Morning* 5500'
Monday Afternoon 4500'

Issued: 7:15 AM PST Sunday, January 3, 2021

5000' Temperatures (°F)

Sunday Sunday Night
Max / Min Max / Min
Olympics 28 / 25 31 / 28
West North 27 / 25 29 / 27
West Central 27 / 25 30 / 27
West South 30 / 25 31 / 29
Stevens Pass 28 / 25 29 / 28
Snoqualmie Pass 29 / 25 31 / 29
East North 27 / 21 27 / 21
East Central 28 / 25 29 / 27
East South 29 / 26 30 / 27
Mt. Hood 34 / 27 34 / 32
Olympics 5000' Temperature Forecast
(Max / Min)
Sunday 28 / 25
Sunday Night 31 / 28
West North 5000' Temperature Forecast
(Max / Min)
Sunday 27 / 25
Sunday Night 29 / 27
West Central 5000' Temperature Forecast
(Max / Min)
Sunday 27 / 25
Sunday Night 30 / 27
West South 5000' Temperature Forecast
(Max / Min)
Sunday 30 / 25
Sunday Night 31 / 29
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Sunday 28 / 25
Sunday Night 29 / 28
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Sunday 29 / 25
Sunday Night 31 / 29
East North 5000' Temperature Forecast
(Max / Min)
Sunday 27 / 21
Sunday Night 27 / 21
East Central 5000' Temperature Forecast
(Max / Min)
Sunday 28 / 25
Sunday Night 29 / 27
East South 5000' Temperature Forecast
(Max / Min)
Sunday 29 / 26
Sunday Night 30 / 27
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Sunday 34 / 27
Sunday Night 34 / 32

Issued: 7:15 AM PST Sunday, January 3, 2021

Ridgeline Winds (mph)

Sunday Morning Sunday Afternoon Sunday Evening Sunday Night
Olympics WSW 5-15 SW 10-20 SSE 5-15 SSE 15-25
West North S 5-15 SW 10-20 SSE 5-15 SE 10-20
West Central SW 5-15 SW 10-20 SE 0-10 SE 10-20
West South WSW 10-20 SW 10-20 SE 5-15 SSE 15-25
Stevens Pass WSW 0-10 WSW 10-20 VAR 0-10 E 0-10
Snoqualmie Pass WSW 10-20 WSW 10-20 ESE 5-15 E 10-20
East North WSW 0-10 WSW 10-20 ESE 0-10 ESE 5-15
East Central WSW 10-20 WSW 10-20 SE 5-15 ESE 5-15
East South WSW 10-20 WSW 10-20 SE 5-15 SSE 10-20
Mt. Hood WSW 10-20 WSW 10-20 SW 15-25 S 20-30
Olympics Ridgeline Winds (mph)
Sunday Morning WSW 5-15
Sunday Afternoon SW 10-20
Sunday Evening SSE 5-15
Sunday Night SSE 15-25
West North Ridgeline Winds (mph)
Sunday Morning S 5-15
Sunday Afternoon SW 10-20
Sunday Evening SSE 5-15
Sunday Night SE 10-20
West Central Ridgeline Winds (mph)
Sunday Morning SW 5-15
Sunday Afternoon SW 10-20
Sunday Evening SE 0-10
Sunday Night SE 10-20
West South Ridgeline Winds (mph)
Sunday Morning WSW 10-20
Sunday Afternoon SW 10-20
Sunday Evening SE 5-15
Sunday Night SSE 15-25
Stevens Pass Ridgeline Winds (mph)
Sunday Morning WSW 0-10
Sunday Afternoon WSW 10-20
Sunday Evening VAR 0-10
Sunday Night E 0-10
Snoqualmie Pass Ridgeline Winds (mph)
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
Sunday Evening ESE 5-15
Sunday Night E 10-20
East North Ridgeline Winds (mph)
Sunday Morning WSW 0-10
Sunday Afternoon WSW 10-20
Sunday Evening ESE 0-10
Sunday Night ESE 5-15
East Central Ridgeline Winds (mph)
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
Sunday Evening SE 5-15
Sunday Night ESE 5-15
East South Ridgeline Winds (mph)
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
Sunday Evening SE 5-15
Sunday Night SSE 10-20
Mt. Hood Ridgeline Winds (mph)
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
Sunday Evening SW 15-25
Sunday Night S 20-30

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

Previous forecast from Jan 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’.