Issued: 2:14 PM PST Saturday, January 2, 2021
by Robert Hahn

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

Weather Synopsis

A strong front will move across the region tonight with heavy rain and snow, strong ridgeline winds, and rapid cooling at the tail end of the precipitation. The front is associated with a deep low moving into southeast Alaska. Snow levels should peak in the evening hours in the 4000-5000 ft range before dropping below Snoqualmie Pass level by morning. Following heavy rain and snow on Saturday, we're expecting another 1-2.5" of water equivalent for the west slopes of the Cascades and Washington Pass, with less for other locations along the east slopes of the Cascades and Hurricane Ridge.

Weak convergence activity may bring some light convergence activity after the front passes through the morning hours. A weak disturbance will enhance light snow showers for northern Washington from the mid-day onwards, with Mt. Baker likely to pick up 2-5" of colder snow. Temperatures on Sunday will be closer to seasonal norms with highs in the upper 20's at 5000 ft.

After a brief relative break on Sunday, light snow starts up by evening in the Mt. Hood area ahead of an Occluded system. In this case, the warm front, cold front, and occluded front attached to the low converge over W Washington as the package lifts NNE across the region Sunday night into Monday, bringing another round of moderate rain and snow which may be heavy for the volcanoes. Precipitation is likely to be heaviest on Monday through early afternoon before the cold front crosses the Cascades late in the day. East flow is likely to keep the passes cold enough for snow until a changeover is likely for Snoqualmie pass sometime in the late morning hours.

 

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
Saturday Night Heavy rain and snow in the evening, then light showers after midnight.
Sunday Light snow showers, heaviest in the morning hours.
Saturday Night Heavy rain and snow until midnight, then tapering to light showers in the early morning hours. Strong winds in the evening.
Sunday Light to occasionally moderate snow showers, heaviest in the middle of the day.
Saturday Night ModeHeavy rain and snow until after midnight, then tapering to light showers and convergence in the early morning hours. Moderate to strong winds in the evening.
Sunday Light snow showers heavier in the northern part of the region.
Saturday Night Heavy rain and snow becoming light by morning. Moderate to strong winds in the evening.
Sunday Decreasing light snow showers.
Saturday Night Heavy rain and snow until after midnight, then tapering to light showers and convergence in the early morning hours. Moderate to strong ridgeline winds in the evening. Light E wind becoming W after midnight at pass level.
Sunday Decreasing light snow showers.
Saturday Night Heavy rain and snow until after midnight, then tapering to light showers and convergence in the early morning hours. Moderate to strong winds in the evening. Light E wind becoming W after midnight at pass level.
Sunday Decreasing light snow showers.
Saturday Night Heavy rain and snow in the evening gradually decreasing throughout the night. Strong winds in the evening.
Sunday Light snow showers, heaviest in the middle of the day.
Saturday Night Heavy rain and snow decreasing after midnight. Strong winds in the evening. Moderate to strong winds in the evening.
Sunday Mostly cloudy with a chance of light snow showers near the Cascade Crest.
Saturday Night Moderate to heavy rain and snow decreasing in the early morning hours. Moderate to strong winds in the evening.
Sunday Mostly cloudy with a chance of light snow showers near the Cascade Crest in the morning.
Saturday Night Increasing heavy rain and snow becoming very heavy after midnight. Increasing strong winds with very strong to extreme gusts.
Sunday Mostly cloudy with a chance of snow flurries. Light snow developing at the end of the day.

Issued: 2:14 PM PST Saturday, January 2, 2021

Precipitation (in)

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

Issued: 2:14 PM PST Saturday, January 2, 2021

Snow Level (ft)

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

Issued: 2:14 PM PST Saturday, January 2, 2021

5000' Temperatures (°F)

Saturday Night Sunday
Max / Min Max / Min
Olympics 32 / 26 29 / 26
West North 30 / 25 27 / 24
West Central 31 / 25 28 / 24
West South 32 / 26 28 / 25
Stevens Pass 31 / 26 29 / 25
Snoqualmie Pass 32 / 26 29 / 25
East North 31 / 24 27 / 22
East Central 31 / 26 29 / 25
East South 33 / 27 29 / 26
Mt. Hood 33 / 31 32 / 27
Olympics 5000' Temperature Forecast
(Max / Min)
Saturday Night 32 / 26
Sunday 29 / 26
West North 5000' Temperature Forecast
(Max / Min)
Saturday Night 30 / 25
Sunday 27 / 24
West Central 5000' Temperature Forecast
(Max / Min)
Saturday Night 31 / 25
Sunday 28 / 24
West South 5000' Temperature Forecast
(Max / Min)
Saturday Night 32 / 26
Sunday 28 / 25
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Saturday Night 31 / 26
Sunday 29 / 25
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Saturday Night 32 / 26
Sunday 29 / 25
East North 5000' Temperature Forecast
(Max / Min)
Saturday Night 31 / 24
Sunday 27 / 22
East Central 5000' Temperature Forecast
(Max / Min)
Saturday Night 31 / 26
Sunday 29 / 25
East South 5000' Temperature Forecast
(Max / Min)
Saturday Night 33 / 27
Sunday 29 / 26
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Saturday Night 33 / 31
Sunday 32 / 27

Issued: 2:14 PM PST Saturday, January 2, 2021

Ridgeline Winds (mph)

Saturday Evening Saturday Night Sunday Morning Sunday Afternoon
Olympics WSW 15-25 W 10-20 WSW 15-25 SW 10-20
West North SW 20-30 W 10-20 SSW 15-25 SW 10-20
West Central SW 25-35 W 10-20 WSW 15-25 WSW 10-20
West South SW 25-35 WSW 20-30 WSW 10-20 WSW 10-20
Stevens Pass SW 20-30 W 15-25 WSW 10-20 WSW 10-20
Snoqualmie Pass SW 30-40 W 15-25 WSW 10-20 WSW 10-20
East North SW 20-30 W 15-25 WSW 10-20 WSW 15-25
East Central WSW 25-35 W 15-25 WSW 15-25 WSW 10-20
East South WSW 25-35 W 25-35 W 15-25 WSW 0-10
Mt. Hood SW 30-40 WSW 35-50 W 15-25 W 15-25
Olympics Ridgeline Winds (mph)
Saturday Evening WSW 15-25
Saturday Night W 10-20
Sunday Morning WSW 15-25
Sunday Afternoon SW 10-20
West North Ridgeline Winds (mph)
Saturday Evening SW 20-30
Saturday Night W 10-20
Sunday Morning SSW 15-25
Sunday Afternoon SW 10-20
West Central Ridgeline Winds (mph)
Saturday Evening SW 25-35
Saturday Night W 10-20
Sunday Morning WSW 15-25
Sunday Afternoon WSW 10-20
West South Ridgeline Winds (mph)
Saturday Evening SW 25-35
Saturday Night WSW 20-30
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
Stevens Pass Ridgeline Winds (mph)
Saturday Evening SW 20-30
Saturday Night W 15-25
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
Snoqualmie Pass Ridgeline Winds (mph)
Saturday Evening SW 30-40
Saturday Night W 15-25
Sunday Morning WSW 10-20
Sunday Afternoon WSW 10-20
East North Ridgeline Winds (mph)
Saturday Evening SW 20-30
Saturday Night W 15-25
Sunday Morning WSW 10-20
Sunday Afternoon WSW 15-25
East Central Ridgeline Winds (mph)
Saturday Evening WSW 25-35
Saturday Night W 15-25
Sunday Morning WSW 15-25
Sunday Afternoon WSW 10-20
East South Ridgeline Winds (mph)
Saturday Evening WSW 25-35
Saturday Night W 25-35
Sunday Morning W 15-25
Sunday Afternoon WSW 0-10
Mt. Hood Ridgeline Winds (mph)
Saturday Evening SW 30-40
Saturday Night WSW 35-50
Sunday Morning W 15-25
Sunday Afternoon W 15-25

Issued: 2:14 PM PST Saturday, January 2, 2021

Extended Weather Synopsis

A quick-moving trough passes over the region bringing light rain/snow showers and cooler temperatures on a westerly flow Monday night. A shallow ridge gives the region a drier day on Tuesday. A N-S oriented front brings SSW flow, significant warming west of the Cascade Crest, and moderate to heavy rain and snow from late Tuesday night into early Wednesday with a weak trough and light showers to follow by mid-day Wednesday.

Extended Snow Level (ft)

Monday Night Tuesday Tuesday Night* Wednesday *
West North 2500' 1500' 2000' 2000'
Snoqualmie Pass 2500' 2000' 2000' 2500'
Mt. Hood 3000' 2500' 3500' 5000'
West North Elevation
Monday Night 2500'
Tuesday 1500'
Tuesday Night* 2000'
Wednesday * 2000'
Snoqualmie Pass Elevation
Monday Night 2500'
Tuesday 2000'
Tuesday Night* 2000'
Wednesday * 2500'
Mt. Hood Elevation
Monday Night 3000'
Tuesday 2500'
Tuesday Night* 3500'
Wednesday * 5000'

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

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’.