Issued: 5:01 PM PST Sunday, January 9, 2022
by Dennis D'Amico

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

Weather Synopsis

Updated weather forecast Monday for Stevens, Snoqualmie and White Pass: Freezing rain possible Cascade Passes Monday afternoon-Tuesday and along east slopes of Cascades Tuesday - Tuesday night. 

After a beautiful day across the region, we'll have a mostly clear evening as a weak frontal system approaches the coast. High clouds will start to spread inland overnight and then thicken rapidly as the front approaches the Olympics around daybreak and the Cascades by mid/late morning. Valley fog will likely develop in many areas where the high clouds are slow to increase. This afternoon temperatures have warmed well above freezing west of the Cascade Pass while many stations are near or below freezing in the Cascade Passes or along the east slopes of the Cascades as the milder air battles out cool E-SE winds and offshore flow. 

A similar temperature/freezing level trend will continue until the frontal passage Monday afternoon and the air mass becomes more mixed during a period of post-frontal westerly flow.  With this frontal system, look for more moderate precipitation and stronger winds along the Olympics and northwest Cascades on Monday.  Light post-frontal showers Monday night will give way to a juicier warm frontal system on Tuesday. Most forecast models take the bulk of the moisture into southern B.C., clipping the Olympics and north Cascades with the heaviest totals, but it's worth watching how far south the frontal boundary extends into our neck of the woods as we get closer.  We'll be on the warm side of the jet stream and snow levels should stay elevated in the 4000-6000' on Tuesday. Mixed precipitation is possible in the Cascade Passes as east flow continues to be a factor. 

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 Night Mostly clear in the evening, then mostly cloudy after midnight with increasing high clouds.
Monday Light to occasionally moderate rain and snow becoming showers in the afternoon. Strong winds.
Sunday Night Mostly clear with increasing high clouds after midnight.
Monday Light to moderate rain and snow developing in the morning. Strong winds.
Sunday Night Mostly clear with increasing high clouds after midnight.
Monday Cloudy, then light to occasionally moderate rain and snow developing in the morning.
Sunday Night Mostly clear with increasing high clouds after midnight.
Monday Partly cloudy in the morning, becoming cloudy with light to occasionally moderate rain and snow in the morning. Precipitation may mix with light freezing rain at times near White Pass. Moderate to strong ridgeline winds.
Sunday Night Mostly clear with increasing high clouds after midnight. Moderate E-SE winds both at ridgeline and Pass level.
Monday Partly cloudy in the morning, becoming cloudy with light to occasionally moderate rain and snow mid-morning. Precipitation may mix with light freezing rain at times. Moderate ridgeline winds. Moderate east winds at Pass level becoming variable in the afternoon.
Sunday Night Mostly clear with increasing high clouds after midnight. Moderate to strong E-SE winds both at ridgeline and Pass level.
Monday Partly cloudy in the morning, becoming cloudy with light to occasionally moderate rain and snow developing mid-morning. Precipitation may mix with light freezing rain at times. Moderate to strong ridgeline winds. Moderate east winds at Pass level becoming variable in the afternoon.
Sunday Night Mostly clear with increasing high clouds late.
Monday Partly cloudy in the morning, becoming cloudy with light rain and snow mid-day. Ridgeline winds increasing during the day.
Sunday Night Mostly clear with increasing high clouds late.
Monday Partly cloudy in the morning, becoming cloudy with light rain and snow mid-day. Ridgeline winds increasing during the day.
Sunday Night Mostly clear with increasing high clouds late.
Monday Partly cloudy in the morning, becoming cloudy with light rain and snow mid-day. Ridgeline winds increasing during the day.
Sunday Night Mostly clear.
Monday Mostly clear in the morning, then becoming cloudy with light rain and snow developing late.

Issued: 5:01 PM PST Sunday, January 9, 2022

Precipitation (in)

Sunday Night Monday Monday Night Tuesday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0 0.25 LT 0.25 0.50
Mt Baker Ski Area 0 0.25 - 0.50 0.25 0.75
Mt. Loop - Barlow Pass 0 0.25 LT 0.25 0.75
Stevens Pass 0 LT 0.25 LT 0.25 0.50
Snoqualmie Pass 0 0.25 LT 0.25 0.50 - 0.75
Crystal Mt 0 LT 0.25 LT 0.10 0.25 - 0.50
Paradise 0 0.25 LT 0.25 0.50 - 0.75
White Pass 0 LT 0.10 LT 0.10 0.25
Washington Pass 0 LT 0.25 LT 0.10 0.25 - 0.50
Mission Ridge 0 LT 0.10 LT 0.10 LT 0.25
Salmon la Sac - Gallagher Head 0 LT 0.10 LT 0.10 0.25 - 0.50
Tieton River - Darland Mt. 0 LT 0.10 LT 0.10 LT 0.25
Mt Hood Meadows 0 LT 0.25 0 LT 0.10
Timberline 0 0.25 0 LT 0.10
Hurricane Ridge Precipitation (in)
Sunday Night 0
Monday 0.25
Monday Night LT 0.25
Tuesday 0.50
Mt Baker Ski Area Precipitation (in)
Sunday Night 0
Monday 0.25 - 0.50
Monday Night 0.25
Tuesday 0.75
Mt. Loop - Barlow Pass Precipitation (in)
Sunday Night 0
Monday 0.25
Monday Night LT 0.25
Tuesday 0.75
Stevens Pass Precipitation (in)
Sunday Night 0
Monday LT 0.25
Monday Night LT 0.25
Tuesday 0.50
Snoqualmie Pass Precipitation (in)
Sunday Night 0
Monday 0.25
Monday Night LT 0.25
Tuesday 0.50 - 0.75
Crystal Mt Precipitation (in)
Sunday Night 0
Monday LT 0.25
Monday Night LT 0.10
Tuesday 0.25 - 0.50
Paradise Precipitation (in)
Sunday Night 0
Monday 0.25
Monday Night LT 0.25
Tuesday 0.50 - 0.75
White Pass Precipitation (in)
Sunday Night 0
Monday LT 0.10
Monday Night LT 0.10
Tuesday 0.25
Washington Pass Precipitation (in)
Sunday Night 0
Monday LT 0.25
Monday Night LT 0.10
Tuesday 0.25 - 0.50
Mission Ridge Precipitation (in)
Sunday Night 0
Monday LT 0.10
Monday Night LT 0.10
Tuesday LT 0.25
Salmon la Sac - Gallagher Head Precipitation (in)
Sunday Night 0
Monday LT 0.10
Monday Night LT 0.10
Tuesday 0.25 - 0.50
Tieton River - Darland Mt. Precipitation (in)
Sunday Night 0
Monday LT 0.10
Monday Night LT 0.10
Tuesday LT 0.25
Mt Hood Meadows Precipitation (in)
Sunday Night 0
Monday LT 0.25
Monday Night 0
Tuesday LT 0.10
Timberline Precipitation (in)
Sunday Night 0
Monday 0.25
Monday Night 0
Tuesday LT 0.10

Issued: 5:01 PM PST Sunday, January 9, 2022

Snow Level (ft)

Sunday Evening* Sunday Night* Monday Morning* Monday Afternoon* Monday Evening Monday Night* Tuesday Morning* Tuesday Afternoon*
Olympics 8000' 6500' 5000' 5000' 5500' 5500' 6000' 6500'
West North 7500' 7000' 6000' 3500' 4500' 5000' 4500' 5000'
West Central 8000' 7000' 6500' 4000' 5000' 5000' 4500' 5000'
West South 8500' 7500' 7000' 4500' 5000' 6000' 6000' 6500'
Stevens Pass 6000' 6000' 6000' 4500' 5000' 4500' 3500' 4000'
Snoqualmie Pass 7000' 7000' 6500' 5000' 5000' 4500' 4500' 5500'
East North 2000' 1000' 1000' 3000' 2500' 2000' 3000' 4000'
East Central 2000' 2000' 2000' 3000' 4000' 3000' 3000' 4000'
East South 6500' 6500' 5000' 4500' 4500' 4500' 4500' 5000'
Mt. Hood 9000' 7000' 7000' 6000' 5500' 6000' 7000' 7500'
Olympics Elevation
Sunday Evening* 8000'
Sunday Night* 6500'
Monday Morning* 5000'
Monday Afternoon* 5000'
Monday Evening 5500'
Monday Night* 5500'
Tuesday Morning* 6000'
Tuesday Afternoon* 6500'
West North Elevation
Sunday Evening* 7500'
Sunday Night* 7000'
Monday Morning* 6000'
Monday Afternoon* 3500'
Monday Evening 4500'
Monday Night* 5000'
Tuesday Morning* 4500'
Tuesday Afternoon* 5000'
West Central Elevation
Sunday Evening* 8000'
Sunday Night* 7000'
Monday Morning* 6500'
Monday Afternoon* 4000'
Monday Evening 5000'
Monday Night* 5000'
Tuesday Morning* 4500'
Tuesday Afternoon* 5000'
West South Elevation
Sunday Evening* 8500'
Sunday Night* 7500'
Monday Morning* 7000'
Monday Afternoon* 4500'
Monday Evening 5000'
Monday Night* 6000'
Tuesday Morning* 6000'
Tuesday Afternoon* 6500'
Stevens Pass Elevation
Sunday Evening* 6000'
Sunday Night* 6000'
Monday Morning* 6000'
Monday Afternoon* 4500'
Monday Evening 5000'
Monday Night* 4500'
Tuesday Morning* 3500'
Tuesday Afternoon* 4000'
Snoqualmie Pass Elevation
Sunday Evening* 7000'
Sunday Night* 7000'
Monday Morning* 6500'
Monday Afternoon* 5000'
Monday Evening 5000'
Monday Night* 4500'
Tuesday Morning* 4500'
Tuesday Afternoon* 5500'
East North Elevation
Sunday Evening* 2000'
Sunday Night* 1000'
Monday Morning* 1000'
Monday Afternoon* 3000'
Monday Evening 2500'
Monday Night* 2000'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
East Central Elevation
Sunday Evening* 2000'
Sunday Night* 2000'
Monday Morning* 2000'
Monday Afternoon* 3000'
Monday Evening 4000'
Monday Night* 3000'
Tuesday Morning* 3000'
Tuesday Afternoon* 4000'
East South Elevation
Sunday Evening* 6500'
Sunday Night* 6500'
Monday Morning* 5000'
Monday Afternoon* 4500'
Monday Evening 4500'
Monday Night* 4500'
Tuesday Morning* 4500'
Tuesday Afternoon* 5000'
Mt. Hood Elevation
Sunday Evening* 9000'
Sunday Night* 7000'
Monday Morning* 7000'
Monday Afternoon* 6000'
Monday Evening 5500'
Monday Night* 6000'
Tuesday Morning* 7000'
Tuesday Afternoon* 7500'

Issued: 5:01 PM PST Sunday, January 9, 2022

5000' Temperatures (°F)

Sunday Night Monday
Max / Min Max / Min
Olympics 34 / 31 34 / 30
West North 34 / 30 33 / 30
West Central 32 / 27 33 / 28
West South 34 / 28 33 / 30
Stevens Pass 30 / 23 33 / 25
Snoqualmie Pass 30 / 26 33 / 26
East North 21 / 16 32 / 17
East Central 28 / 22 33 / 20
East South 30 / 24 33 / 27
Mt. Hood 32 / 25 35 / 28
Olympics 5000' Temperature Forecast
(Max / Min)
Sunday Night 34 / 31
Monday 34 / 30
West North 5000' Temperature Forecast
(Max / Min)
Sunday Night 34 / 30
Monday 33 / 30
West Central 5000' Temperature Forecast
(Max / Min)
Sunday Night 32 / 27
Monday 33 / 28
West South 5000' Temperature Forecast
(Max / Min)
Sunday Night 34 / 28
Monday 33 / 30
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Sunday Night 30 / 23
Monday 33 / 25
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Sunday Night 30 / 26
Monday 33 / 26
East North 5000' Temperature Forecast
(Max / Min)
Sunday Night 21 / 16
Monday 32 / 17
East Central 5000' Temperature Forecast
(Max / Min)
Sunday Night 28 / 22
Monday 33 / 20
East South 5000' Temperature Forecast
(Max / Min)
Sunday Night 30 / 24
Monday 33 / 27
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Sunday Night 32 / 25
Monday 35 / 28

Issued: 5:01 PM PST Sunday, January 9, 2022

Ridgeline Winds (mph)

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

Issued: 5:01 PM PST Sunday, January 9, 2022

Extended Weather Synopsis

A similar pattern will continue Tuesday night through at least Wednesday night with several waves developing along a frontal boundary and slamming into southern/central British Columbia and clipping our northern mountains with more moderate rain and snow that tapers further south. There's fair agreement on the axis of heavier precipitation with this likely atmospheric river event, but again, slight changes could bring much heavier precipitation further south into the Washington Cascades. Snow levels stay on the mild side and strong westerly ridgeline winds should eventually overwhelm cool low-level easterlies in the Passes during this stretch.  We may get a brief cool down with some measurable snow at lower elevations late Thursday or Thursday night as the trailing cold front passes through.  

Extended Snow Level (ft)

Tuesday Night* Wednesday * Wednesday Night* Thursday
West North 6000' 7500' 6500' 6000'
Snoqualmie Pass 6500' 7500' 7000' 6000'
Mt. Hood 8000' 11000' 10000' 7500'
West North Elevation
Tuesday Night* 6000'
Wednesday * 7500'
Wednesday Night* 6500'
Thursday 6000'
Snoqualmie Pass Elevation
Tuesday Night* 6500'
Wednesday * 7500'
Wednesday Night* 7000'
Thursday 6000'
Mt. Hood Elevation
Tuesday Night* 8000'
Wednesday * 11000'
Wednesday Night* 10000'
Thursday 7500'

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

Previous forecast from Jan 9, 2022

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’.