Issued: 4:18 PM PST Wednesday, January 4, 2023
by Robert Hahn

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

Weather Synopsis

Forecast adjusted to reflect higher wind speeds in the Cascades West South zone Wednesday night and Thursday.

Satellite imagery depicts a deep low off the California-Oregon coastline Wednesday afternoon. A warm front draped NW to SE across Oregon spreads moderate snowfall that has just started up in the Mt. Hood area. This front will slow as it spreads a band of precipitation into Washington overnight with light to moderate snow enhanced on the eastern side of the Cascades and Olympics. Temperatures stay cold along the east slopes and through the mountain gaps (such as Snoqualmie and White Passes) as strong E flow peaks Wednesday night. The front weakens over the northern Cascades Thursday morning. Southern parts of the region should be milder and drier in the warm sector of the storm with more active weather returning with the trailing cold front later in the day, maintaining the windy conditions now out of the SSW. This will likely result in snow levels bumping above Snoqualmie Pass level through evening hours before cooling gradually kicks in.

A subtle upper trough transits the area Thursday night with SSW winds continuing the rain and snow and focusing it on the Cascades volcanoes. Mt. Baker in particularly could see heavy precipitation Thursday night before a slight easing of the precipitation as a subtle ridge moves through and another powerful system moves in to the PNW coastline.

Snow lines will fluctuate with each passing wave but the general trend will be warming on Wednesday night and Thursday, cooling Thursday night, and slight warming on Friday.

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
Wednesday Night Increasing light rain and snow (heavier southern and eastern sides of the range).
Thursday Increasing light rain and snow (heavier southern side of the range).
Wednesday Night Increasing light snow becoming moderate at times overnight.
Thursday Light to moderate rain and snow.
Wednesday Night Increasing light snow.
Thursday Light rain and snow at times.
Wednesday Night Light rain and snow. Strong ridgeline winds near the Cascade Crest.
Thursday Periods of light to moderate rain and snow, heaviest at Paradise.
Wednesday Night Periods of light snow. Moderate to strong ridgeline and E wind at the Pass. Strong winds west of the Cascade Crest.
Thursday Periods of light snow mixing with rain west of the Pass. Decreasing moderate to strong ridgeline and E wind at the Pass.
Wednesday Night Periods of light snow. Moderate to strong ridgeline and E wind at the Pass. Strong winds west of the Cascade Crest.
Thursday Periods of light snow mixing with rain from late morning onwards. Decreasing moderate to strong ridgeline and E wind at the Pass.
Wednesday Night Periods of light snow. Strong ridgeline wind gusts.
Thursday Periods of light snow. Strong ridgeline wind gusts.
Wednesday Night Periods of light to occasionally moderate snow. Strong ridgeline wind gusts.
Thursday Periods of light snow, mixing with rain at lower elevations in the afternoon. Strong ridgeline wind gusts.
Wednesday Night Moderate snow.
Thursday Periods of light to moderate rain and snow.
Wednesday Night Light to moderate rain and snow in the evening becoming light overnight. Moderate to strong ridgeline winds.
Thursday Mostly cloudy with a chance of light rain or snow.

Issued: 4:18 PM PST Wednesday, January 4, 2023

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

Issued: 4:18 PM PST Wednesday, January 4, 2023

Snow Level (ft)

Wednesday Evening* Wednesday Night* Thursday Morning* Thursday Afternoon* Thursday Evening* Thursday Night* Friday Morning* Friday Afternoon*
Olympics 5000' 4500' 4500' 5500' 5000' 3500' 3500' 4500'
West North 2500' 3500' 4000' 4500' 4000' 3000' 3000' 3500'
West Central 2000' 3500' 3500' 4000' 4000' 3000' 3000' 4000'
West South 2500' 3500' 3500' 4500' 4000' 3500' 3000' 4000'
Stevens Pass 1500' 2000' 2500' 3500' 3000' 2500' 2500' 3500'
Snoqualmie Pass 2000' 2500' 2500' 3500' 3500' 3000' 3000' 3500'
East North 1500' 1000' 1500' 3000' 3000' 2500' 2000' 3000'
East Central 1500' 1500' 2000' 3000' 3000' 2500' 2000' 3000'
East South 2000' 2000' 3000' 3500' 3500' 3500' 2500' 4000'
Mt. Hood 4000' 4500' 4500' 4500' 4500' 3500' 3000' 4500'
Olympics Elevation
Wednesday Evening* 5000'
Wednesday Night* 4500'
Thursday Morning* 4500'
Thursday Afternoon* 5500'
Thursday Evening* 5000'
Thursday Night* 3500'
Friday Morning* 3500'
Friday Afternoon* 4500'
West North Elevation
Wednesday Evening* 2500'
Wednesday Night* 3500'
Thursday Morning* 4000'
Thursday Afternoon* 4500'
Thursday Evening* 4000'
Thursday Night* 3000'
Friday Morning* 3000'
Friday Afternoon* 3500'
West Central Elevation
Wednesday Evening* 2000'
Wednesday Night* 3500'
Thursday Morning* 3500'
Thursday Afternoon* 4000'
Thursday Evening* 4000'
Thursday Night* 3000'
Friday Morning* 3000'
Friday Afternoon* 4000'
West South Elevation
Wednesday Evening* 2500'
Wednesday Night* 3500'
Thursday Morning* 3500'
Thursday Afternoon* 4500'
Thursday Evening* 4000'
Thursday Night* 3500'
Friday Morning* 3000'
Friday Afternoon* 4000'
Stevens Pass Elevation
Wednesday Evening* 1500'
Wednesday Night* 2000'
Thursday Morning* 2500'
Thursday Afternoon* 3500'
Thursday Evening* 3000'
Thursday Night* 2500'
Friday Morning* 2500'
Friday Afternoon* 3500'
Snoqualmie Pass Elevation
Wednesday Evening* 2000'
Wednesday Night* 2500'
Thursday Morning* 2500'
Thursday Afternoon* 3500'
Thursday Evening* 3500'
Thursday Night* 3000'
Friday Morning* 3000'
Friday Afternoon* 3500'
East North Elevation
Wednesday Evening* 1500'
Wednesday Night* 1000'
Thursday Morning* 1500'
Thursday Afternoon* 3000'
Thursday Evening* 3000'
Thursday Night* 2500'
Friday Morning* 2000'
Friday Afternoon* 3000'
East Central Elevation
Wednesday Evening* 1500'
Wednesday Night* 1500'
Thursday Morning* 2000'
Thursday Afternoon* 3000'
Thursday Evening* 3000'
Thursday Night* 2500'
Friday Morning* 2000'
Friday Afternoon* 3000'
East South Elevation
Wednesday Evening* 2000'
Wednesday Night* 2000'
Thursday Morning* 3000'
Thursday Afternoon* 3500'
Thursday Evening* 3500'
Thursday Night* 3500'
Friday Morning* 2500'
Friday Afternoon* 4000'
Mt. Hood Elevation
Wednesday Evening* 4000'
Wednesday Night* 4500'
Thursday Morning* 4500'
Thursday Afternoon* 4500'
Thursday Evening* 4500'
Thursday Night* 3500'
Friday Morning* 3000'
Friday Afternoon* 4500'

Issued: 4:18 PM PST Wednesday, January 4, 2023

5000' Temperatures (°F)

Wednesday Night Thursday
Max / Min Max / Min
Olympics 34 / 30 33 / 31
West North 30 / 28 34 / 30
West Central 27 / 23 30 / 27
West South 30 / 25 34 / 29
Stevens Pass 26 / 20 30 / 25
Snoqualmie Pass 27 / 21 30 / 27
East North 21 / 17 27 / 22
East Central 26 / 20 31 / 26
East South 25 / 20 31 / 25
Mt. Hood 32 / 28 34 / 32
Olympics 5000' Temperature Forecast
(Max / Min)
Wednesday Night 34 / 30
Thursday 33 / 31
West North 5000' Temperature Forecast
(Max / Min)
Wednesday Night 30 / 28
Thursday 34 / 30
West Central 5000' Temperature Forecast
(Max / Min)
Wednesday Night 27 / 23
Thursday 30 / 27
West South 5000' Temperature Forecast
(Max / Min)
Wednesday Night 30 / 25
Thursday 34 / 29
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Wednesday Night 26 / 20
Thursday 30 / 25
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Wednesday Night 27 / 21
Thursday 30 / 27
East North 5000' Temperature Forecast
(Max / Min)
Wednesday Night 21 / 17
Thursday 27 / 22
East Central 5000' Temperature Forecast
(Max / Min)
Wednesday Night 26 / 20
Thursday 31 / 26
East South 5000' Temperature Forecast
(Max / Min)
Wednesday Night 25 / 20
Thursday 31 / 25
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Wednesday Night 32 / 28
Thursday 34 / 32

Issued: 4:18 PM PST Wednesday, January 4, 2023

Ridgeline Winds (mph)

Wednesday Evening Wednesday Night Thursday Morning Thursday Afternoon
Olympics SSE 15-25 S 20-30 SSE 20-30 SSE 25-35
West North SSE 20-30 SSE 20-30 SSE 20-30 SSE 20-30
West Central ESE 25-35 ESE 20-30 ESE 15-25 SE 15-25
West South SE 30-40 SE 30-40 SSE 25-35 SSE 20-30
Stevens Pass ESE 25-35 ESE 20-30 ESE 20-30 SE 15-25
Snoqualmie Pass SE 25-35 SE 20-30 SE 20-30 SE 20-30
East North SE 15-25 SE 15-25 SE 10-20 SE 10-20
East Central ESE 20-30 SE 15-25 SE 15-25 SSE 20-30
East South SE 10-20 SE 10-20 SE 10-20 SSE 10-20
Mt. Hood SE 25-35 SE 25-35 SSE 20-30 SSW 25-35
Olympics Ridgeline Winds (mph)
Wednesday Evening SSE 15-25
Wednesday Night S 20-30
Thursday Morning SSE 20-30
Thursday Afternoon SSE 25-35
West North Ridgeline Winds (mph)
Wednesday Evening SSE 20-30
Wednesday Night SSE 20-30
Thursday Morning SSE 20-30
Thursday Afternoon SSE 20-30
West Central Ridgeline Winds (mph)
Wednesday Evening ESE 25-35
Wednesday Night ESE 20-30
Thursday Morning ESE 15-25
Thursday Afternoon SE 15-25
West South Ridgeline Winds (mph)
Wednesday Evening SE 30-40
Wednesday Night SE 30-40
Thursday Morning SSE 25-35
Thursday Afternoon SSE 20-30
Stevens Pass Ridgeline Winds (mph)
Wednesday Evening ESE 25-35
Wednesday Night ESE 20-30
Thursday Morning ESE 20-30
Thursday Afternoon SE 15-25
Snoqualmie Pass Ridgeline Winds (mph)
Wednesday Evening SE 25-35
Wednesday Night SE 20-30
Thursday Morning SE 20-30
Thursday Afternoon SE 20-30
East North Ridgeline Winds (mph)
Wednesday Evening SE 15-25
Wednesday Night SE 15-25
Thursday Morning SE 10-20
Thursday Afternoon SE 10-20
East Central Ridgeline Winds (mph)
Wednesday Evening ESE 20-30
Wednesday Night SE 15-25
Thursday Morning SE 15-25
Thursday Afternoon SSE 20-30
East South Ridgeline Winds (mph)
Wednesday Evening SE 10-20
Wednesday Night SE 10-20
Thursday Morning SE 10-20
Thursday Afternoon SSE 10-20
Mt. Hood Ridgeline Winds (mph)
Wednesday Evening SE 25-35
Wednesday Night SE 25-35
Thursday Morning SSE 20-30
Thursday Afternoon SSW 25-35

Issued: 4:18 PM PST Wednesday, January 4, 2023

Extended Weather Synopsis

Active weather continues with snow levels near pass level through the weekend. A deep low passes north of Vancouver Island Friday night with a frontal passage over our region. Several more waves move up from the southwest on Saturday and Sunday and it is too early to discern the timing.

Extended Snow Level (ft)

Friday Night* Saturday * Saturday Night* Sunday *
West North 3500' 3500' 2000' 2500'
Snoqualmie Pass 3000' 3000' 2500' 3500'
Mt. Hood 4000' 3500' 4000' 4000'
West North Elevation
Friday Night* 3500'
Saturday * 3500'
Saturday Night* 2000'
Sunday * 2500'
Snoqualmie Pass Elevation
Friday Night* 3000'
Saturday * 3000'
Saturday Night* 2500'
Sunday * 3500'
Mt. Hood Elevation
Friday Night* 4000'
Saturday * 3500'
Saturday Night* 4000'
Sunday * 4000'

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

Previous forecast from Jan 4, 2023

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’.