Issued: 2:09 PM PST Wednesday, January 13, 2021
by Robert Hahn

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

Weather Synopsis

A strong frontal system that ended a 48-hour atmospheric river event has pushed well to our east. The lingering showers in decreasing westerly flow should taper off over the central Washington Cascades on Wednesday evening. This leaves the region under partly clearing skies with cool temperatures. A ridge begins to build over the region, bringing milder temperatures to southern parts of the forecast region. This warming will accelerate Thursday as the ridge continues to amplify with the ridge axis over the region. A cold pool east of the Cascades below 4500 ft combined with E moderate E flow through the passes should keep the passes mostly cool on Thursday. Temperatures may rise just above freezing Thursday afternoon at locations such as Snoqualmie Pass. Meanwhile, freezing levels should be 10,500-12,000 ft in locations such as the Olympics and Mt. Hood.

A frontal system offshore will send most of its energy into British Columbia. Our region gets the weak tail end of the system late Thursday night as the ridge of high pressure slides eastward. The frontal passage should occur early Friday morning with light rain and snow from midnight Thursday night until post-frontal shower activity tapers off Friday afternoon. Snow levels should be in the 3500-8000 ft range with some lower snow levels east of the Cascade Crest and to the north, while milder air will be harder to displace further south.

Weather Forecast

Use dropdown to select your zone
Wednesday Night Partly to mostly clear in the evening, then becoming mostly cloudy.
Thursday Mostly cloudy early with increasing sunshine throughout the day.

Precipitation (in)

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

Snow Level (ft)

Wednesday Evening Wednesday Night * Thursday Morning * Thursday Afternoon * Thursday Evening * Thursday Night * Friday Morning Friday Afternoon
Olympics 2500' 3500' 5500' 10500' 8500' 7500' 5000' 5000'
West North 1500' 2000' 2500' 6500' 7000' 6500' 5000' 4500'
West Central 2000' 2000' 3500' 7000' 7000' 6500' 5500' 5000'
West South 2000' 2500' 5000' 10500' 8000' 7000' 6500' 6000'
Stevens Pass 2000' 2000' 3000' 4000' 4500' 5000' 4500' 5000'
Snoqualmie Pass 2000' 2500' 3500' 8000' 6500' 5500' 5500' 5500'
East North 1500' 1500' 2000' 3500' 3500' 3500' 4000' 5000'
East Central 2000' 2000' 3500' 4000' 5500' 5500' 4500' 5500'
East South 2500' 3000' 4500' 7000' 7000' 7000' 7000' 6500'
Mt. Hood 3500' 5000' 8500' 12000' 10000' 9500' 8000' 7500'
Olympics Elevation
Wednesday Evening 2500'
Wednesday Night * 3500'
Thursday Morning * 5500'
Thursday Afternoon * 10500'
Thursday Evening * 8500'
Thursday Night * 7500'
Friday Morning 5000'
Friday Afternoon 5000'
West North Elevation
Wednesday Evening 1500'
Wednesday Night * 2000'
Thursday Morning * 2500'
Thursday Afternoon * 6500'
Thursday Evening * 7000'
Thursday Night * 6500'
Friday Morning 5000'
Friday Afternoon 4500'
West Central Elevation
Wednesday Evening 2000'
Wednesday Night * 2000'
Thursday Morning * 3500'
Thursday Afternoon * 7000'
Thursday Evening * 7000'
Thursday Night * 6500'
Friday Morning 5500'
Friday Afternoon 5000'
West South Elevation
Wednesday Evening 2000'
Wednesday Night * 2500'
Thursday Morning * 5000'
Thursday Afternoon * 10500'
Thursday Evening * 8000'
Thursday Night * 7000'
Friday Morning 6500'
Friday Afternoon 6000'
Stevens Pass Elevation
Wednesday Evening 2000'
Wednesday Night * 2000'
Thursday Morning * 3000'
Thursday Afternoon * 4000'
Thursday Evening * 4500'
Thursday Night * 5000'
Friday Morning 4500'
Friday Afternoon 5000'
Snoqualmie Pass Elevation
Wednesday Evening 2000'
Wednesday Night * 2500'
Thursday Morning * 3500'
Thursday Afternoon * 8000'
Thursday Evening * 6500'
Thursday Night * 5500'
Friday Morning 5500'
Friday Afternoon 5500'
East North Elevation
Wednesday Evening 1500'
Wednesday Night * 1500'
Thursday Morning * 2000'
Thursday Afternoon * 3500'
Thursday Evening * 3500'
Thursday Night * 3500'
Friday Morning 4000'
Friday Afternoon 5000'
East Central Elevation
Wednesday Evening 2000'
Wednesday Night * 2000'
Thursday Morning * 3500'
Thursday Afternoon * 4000'
Thursday Evening * 5500'
Thursday Night * 5500'
Friday Morning 4500'
Friday Afternoon 5500'
East South Elevation
Wednesday Evening 2500'
Wednesday Night * 3000'
Thursday Morning * 4500'
Thursday Afternoon * 7000'
Thursday Evening * 7000'
Thursday Night * 7000'
Friday Morning 7000'
Friday Afternoon 6500'
Mt. Hood Elevation
Wednesday Evening 3500'
Wednesday Night * 5000'
Thursday Morning * 8500'
Thursday Afternoon * 12000'
Thursday Evening * 10000'
Thursday Night * 9500'
Friday Morning 8000'
Friday Afternoon 7500'

5000' Temperatures (°F)

Wednesday Night Thursday
Max / Min Max / Min
Olympics 32 / 24 41 / 32
West North 26 / 21 37 / 26
West Central 29 / 21 35 / 29
West South 31 / 24 35 / 31
Stevens Pass 29 / 22 32 / 29
Snoqualmie Pass 31 / 23 33 / 31
East North 21 / 16 24 / 18
East Central 27 / 22 30 / 27
East South 30 / 22 32 / 30
Mt. Hood 40 / 29 46 / 40
Olympics 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 32 / 24
Thursday 4am - 4pm 41 / 32
West North 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 26 / 21
Thursday 4am - 4pm 37 / 26
West Central 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 29 / 21
Thursday 4am - 4pm 35 / 29
West South 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 31 / 24
Thursday 4am - 4pm 35 / 31
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 29 / 22
Thursday 4am - 4pm 32 / 29
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 31 / 23
Thursday 4am - 4pm 33 / 31
East North 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 21 / 16
Thursday 4am - 4pm 24 / 18
East Central 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 27 / 22
Thursday 4am - 4pm 30 / 27
East South 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 30 / 22
Thursday 4am - 4pm 32 / 30
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Wednesday 4pm - 4am 40 / 29
Thursday 4am - 4pm 46 / 40

Ridgeline Winds (mph)

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

Extended Weather Synopsis

Broad ridging across the western US amplifies Friday night and Saturday, centering along the west coast and bringing dry weather. Another tail end of a weakening frontal system moves through late Saturday night and Sunday morning with light rain and snow tapering to light post-frontal shower activity by Sunday afternoon.

Extended Snow Level (ft)

Friday Night Saturday * Saturday Night * Sunday
West North 3500' 3500' 5000' 2500'
Snoqualmie Pass 4000' 4500' 7000' 4500'
Mt. Hood 7000' 8500' 10500' 5500'
West North Elevation
Friday Night 3500'
Saturday * 3500'
Saturday Night * 5000'
Sunday 2500'
Snoqualmie Pass Elevation
Friday Night 4000'
Saturday * 4500'
Saturday Night * 7000'
Sunday 4500'
Mt. Hood Elevation
Friday Night 7000'
Saturday * 8500'
Saturday Night * 10500'
Sunday 5500'

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

Previous forecast from Jan 13, 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’.