Issued: 7:20 AM PST Monday, January 11, 2021
by Robert Hahn

Jump to: Weather Forecast I Snow Level I Precipitation I Ridgeline Winds I

Weather Synopsis

An impressive feed of increasingly subtropical moisture is approaching the Pacific Northwest from Monday through early Wednesday. The first wave in a series of three moves a frontal rain band eastward on Monday. Moderate to heavy rain has started in the Olympics and Mt. Baker area and should spread throughout the Washington Cascades by late morning. Light E flow at low levels should keep the passes cool today while mild air west of the Cascade Crest raises the snow level from 4000-5000 ft in areas not cooled by E flow. Mt Baker should expect a foot of snow today above 4500, but freezing levels are uncertain this morning (4000-4500) and should drop slightly during the afternoon. Paradise could see 8-12" while Snoqualmie and Stevens Passes can expect 3-6" of snow. Mt. Hood should stay mostly dry.

The second wave of precipitation arrives this evening from the SW, bringing even heavier moisture and another increase in winds. The precipitation should spread throughout the region in including Mt. Hood. Many locations can expect 1-2" of snow water equivalent Monday night. This round of precipitation and wind comes with moderate E flow keeping the central Cascades Passes mostly cold enough for snow. Snoqualmie Pass could see a changeover by Tuesday morning or shortly thereafter as the warm SW winds overcome the cooler E flow.

There's really no break as the moisture feed continues ahead of a third wave slated to arrive late Tuesday and Tuesday night. Snow levels continue to climb and most areas except Washington pass should see rain up to 5500-8000 ft while Washington Pass stays cold enough for snow. Moderate to occasionally strong winds should ramp up late in the day.

Weather Forecast

Use dropdown to select your zone
Monday Light to moderate rain and snow.
Monday Night Heavy rain and snow.

Precipitation (in)

Monday Monday Night Tuesday
4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0.25 - 0.50 1.00 0.25 - 0.50
Mt Baker Ski Area 1.00 1.50 - 2.00 1.00 - 1.50
Mt. Loop - Barlow Pass 0.75 -1.00 1.50 - 2.00 2.00
Stevens Pass 0.25 - 0.50 0.75 -1.00 1.00
Snoqualmie Pass 0.50 1.00 - 1.50 2.00
Crystal Mt 0.25 - 0.50 1.50 1.00 - 1.50
Paradise 1.00 2.00 2.50
White Pass 0.25 0.50 1.00 - 1.50
Washington Pass 0.25 - 0.50 0.75 -1.00 1.00
Mission Ridge LT 0.25 0.75 -1.00 0.50
Salmon la Sac - Gallagher Head 0.25 - 0.50 1.00 - 1.50 1.00
Tieton River - Darland Mt. LT 0.25 0.75 0.75 -1.00
Mt Hood Meadows LT 0.10 0.50 - 0.75 2.00 - 2.50
Timberline LT 0.10 0.50 - 0.75 2.00 - 2.50
Hurricane Ridge Precipitation (in)
Monday 0.25 - 0.50
Monday Night 1.00
Tuesday 0.25 - 0.50
Mt Baker Ski Area Precipitation (in)
Monday 1.00
Monday Night 1.50 - 2.00
Tuesday 1.00 - 1.50
Mt. Loop - Barlow Pass Precipitation (in)
Monday 0.75 -1.00
Monday Night 1.50 - 2.00
Tuesday 2.00
Stevens Pass Precipitation (in)
Monday 0.25 - 0.50
Monday Night 0.75 -1.00
Tuesday 1.00
Snoqualmie Pass Precipitation (in)
Monday 0.50
Monday Night 1.00 - 1.50
Tuesday 2.00
Crystal Mt Precipitation (in)
Monday 0.25 - 0.50
Monday Night 1.50
Tuesday 1.00 - 1.50
Paradise Precipitation (in)
Monday 1.00
Monday Night 2.00
Tuesday 2.50
White Pass Precipitation (in)
Monday 0.25
Monday Night 0.50
Tuesday 1.00 - 1.50
Washington Pass Precipitation (in)
Monday 0.25 - 0.50
Monday Night 0.75 -1.00
Tuesday 1.00
Mission Ridge Precipitation (in)
Monday LT 0.25
Monday Night 0.75 -1.00
Tuesday 0.50
Salmon la Sac - Gallagher Head Precipitation (in)
Monday 0.25 - 0.50
Monday Night 1.00 - 1.50
Tuesday 1.00
Tieton River - Darland Mt. Precipitation (in)
Monday LT 0.25
Monday Night 0.75
Tuesday 0.75 -1.00
Mt Hood Meadows Precipitation (in)
Monday LT 0.10
Monday Night 0.50 - 0.75
Tuesday 2.00 - 2.50
Timberline Precipitation (in)
Monday LT 0.10
Monday Night 0.50 - 0.75
Tuesday 2.00 - 2.50

Snow Level (ft)

Monday Morning Monday Afternoon Monday Evening Monday Night Tuesday Morning Tuesday Afternoon
Olympics 4500' 4500' 4500' 6000' 6500' 6500'
West North 4000' 3500' 3500' 3500' 4000' 5500'
West Central 3500' 3500' 4000' 3500' 4500' 6500'
West South 4000' 4500' 4500' 5000' 6500' 7000'
Stevens Pass 2500' 3000' 3000' 3000' 3500' 6000'
Snoqualmie Pass 3000' 3000' 3000' 3000' 5500' 6500'
East North 2500' 3000' 3000' 2500' 6500' 3500'
East Central 2500' 3000' 3000' 3000' 7500' 6000'
East South 3500' 4500' 5000' 4500' 6500' 7000'
Mt. Hood 5000' 6000' 6500' 7000' 7500' 8000'
Olympics Elevation
Monday Morning 4500'
Monday Afternoon 4500'
Monday Evening 4500'
Monday Night 6000'
Tuesday Morning 6500'
Tuesday Afternoon 6500'
West North Elevation
Monday Morning 4000'
Monday Afternoon 3500'
Monday Evening 3500'
Monday Night 3500'
Tuesday Morning 4000'
Tuesday Afternoon 5500'
West Central Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 4000'
Monday Night 3500'
Tuesday Morning 4500'
Tuesday Afternoon 6500'
West South Elevation
Monday Morning 4000'
Monday Afternoon 4500'
Monday Evening 4500'
Monday Night 5000'
Tuesday Morning 6500'
Tuesday Afternoon 7000'
Stevens Pass Elevation
Monday Morning 2500'
Monday Afternoon 3000'
Monday Evening 3000'
Monday Night 3000'
Tuesday Morning 3500'
Tuesday Afternoon 6000'
Snoqualmie Pass Elevation
Monday Morning 3000'
Monday Afternoon 3000'
Monday Evening 3000'
Monday Night 3000'
Tuesday Morning 5500'
Tuesday Afternoon 6500'
East North Elevation
Monday Morning 2500'
Monday Afternoon 3000'
Monday Evening 3000'
Monday Night 2500'
Tuesday Morning 6500'
Tuesday Afternoon 3500'
East Central Elevation
Monday Morning 2500'
Monday Afternoon 3000'
Monday Evening 3000'
Monday Night 3000'
Tuesday Morning 7500'
Tuesday Afternoon 6000'
East South Elevation
Monday Morning 3500'
Monday Afternoon 4500'
Monday Evening 5000'
Monday Night 4500'
Tuesday Morning 6500'
Tuesday Afternoon 7000'
Mt. Hood Elevation
Monday Morning 5000'
Monday Afternoon 6000'
Monday Evening 6500'
Monday Night 7000'
Tuesday Morning 7500'
Tuesday Afternoon 8000'

5000' Temperatures (°F)

Monday Monday Night
Max / Min Max / Min
Olympics 32 / 30 34 / 31
West North 31 / 29 31 / 29
West Central 31 / 27 31 / 29
West South 32 / 31 33 / 31
Stevens Pass 31 / 26 29 / 27
Snoqualmie Pass 31 / 27 31 / 28
East North 29 / 24 26 / 24
East Central 32 / 26 30 / 28
East South 32 / 29 33 / 30
Mt. Hood 37 / 30 37 / 33
Olympics 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 32 / 30
Monday 4pm - 4am 34 / 31
West North 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 31 / 29
Monday 4pm - 4am 31 / 29
West Central 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 31 / 27
Monday 4pm - 4am 31 / 29
West South 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 32 / 31
Monday 4pm - 4am 33 / 31
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 31 / 26
Monday 4pm - 4am 29 / 27
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 31 / 27
Monday 4pm - 4am 31 / 28
East North 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 29 / 24
Monday 4pm - 4am 26 / 24
East Central 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 32 / 26
Monday 4pm - 4am 30 / 28
East South 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 32 / 29
Monday 4pm - 4am 33 / 30
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday 4am - 4pm 37 / 30
Monday 4pm - 4am 37 / 33

Ridgeline Winds (mph)

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

Jump to: Weather Forecast I Snow Level I Precipitation I Ridgeline Winds I

Previous forecast from Jan 10, 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’.