Issued: 2:13 PM PST Sunday, December 24, 2023
by Robert Hahn

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

Weather Synopsis

A very active weather pattern will impact the Pacific Northwest over the next 3-4 days.

A weakening trough brought light bands of snowfall as it passed over the area on Sunday afternoon along with a trace to a few inches of snow.  After a brief warm-up for the west slopes of the Cascades during the morning hours, cooler temperatures returned later in the day. Some flurries and extensive cloud cover linger over the area Sunday evening.

A ridge over the Rockies directs the storm track northward into British Columbia, allowing an atmospheric river Monday through early Tuesday to bring warm air into areas west of the Cascade Crest, while a strong cold air pool battles for precipitation type near the Cascade Crest. The warm front approaches from the southwest late Sunday night, spreading light snowfall into the Mt Hood and Olympics areas in the early morning hours.

Increasing light to moderate precipitation spreads from SW to NE across the region Monday morning. Southerly winds ahead of the system ramp up during the day, with moderate to locally strong winds impacting the Olympics and Mt Baker. Easterly flow also peaks Monday morning, bringing moderate to locally strong and cold east flow through the mountain gaps. As snow levels rise in areas further from the Cascade Crest, the passes likely remain all snow or freezing rain mix with moderate precipitation continuing to stream on Monday night.

A frontal passage in the early morning hours on Tuesday may result in a brief period of W flow with lighter rain and snow shower activity behind the front. Expect a changeover to rain at Snoqualmie Pass level. E flow returns Tuesday afternoon with the potential to lower snow levels to Snoqualmie Pass elevation.

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 Cloudy with light rain or snow developing in the early morning hours.
Monday Moderate rain and snow changing to all rain. Precipitation may be heavy in the southern Olympics.
Sunday Night Snow flurries in the evening hours, then cloudy skies.
Monday Light snow becomes moderate, then heavy, and changes to rain in the 10 AM to 1 PM time frame. Increasing moderate to strong ridgeline winds.
Sunday Night Snow flurries in the evening hours, then cloudy skies.
Monday Light snow becomes moderate in the afternoon and mixes with or changes to rain in areas away from the Cascade Crest.
Sunday Night Cloudy with snow flurries at times.
Monday Light snow becomes moderate in the afternoon and mixes with or changes to rain in areas away from the Cascade Crest.
Sunday Night Cloudy with snow flurries at times. Mostly light ridgeline and E winds at the Pass.
Monday Light snow becoming moderate in the afternoon. Moderate ridgeline winds and light to moderate E winds at the Pass.
Sunday Night Cloudy with snow flurries at times. Light to moderate ridgeline and E winds at the Pass.
Monday Light snow becoming moderate in the afternoon. Moderate to strong ridgeline winds and moderate E winds at the Pass.
Sunday Night A few snow flurries in the evening, then cloudy skies.
Monday Periods of light snow from late morning onwards.
Sunday Night A few snow flurries in the evening, then cloudy skies. Light to moderate ridgeline winds.
Monday Periods of light snow. Moderate ridgeline winds.
Sunday Night Snow flurries in the evening hours, then light snow develops in the early morning hours.
Monday Periods of light snow.
Sunday Night Cloudy with periods of light snow, mainly after midnight. Moderate ridgeline winds.
Monday Light snow possibly mixing with or changing to rain on the west side of Mt Hood. Moderate ridgeline winds with strong gusts.

Issued: 2:13 PM PST Sunday, December 24, 2023

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 LT 0.10 0.50 1.00 - 1.50 LT 0.10
Mt Baker Ski Area LT 0.25 1.00 2.00 - 2.50 0.50
Mt. Loop - Barlow Pass LT 0.10 0.50 - 0.75 1.00 - 1.50 LT 0.25
Stevens Pass LT 0.10 0.25 - 0.50 0.50 LT 0.25
Snoqualmie Pass LT 0.10 0.50 0.25 - 0.50 0.25
Crystal Mt LT 0.10 0.25 0.75 LT 0.10
Paradise LT 0.10 0.75 -1.00 1.00 0.25
White Pass LT 0.10 0.25 - 0.50 0.25 - 0.50 LT 0.25
Washington Pass LT 0.10 LT 0.10 0.25 - 0.50 0.25
Mission Ridge 0 0.25 0.50 LT 0.10
Salmon la Sac - Gallagher Head LT 0.10 0.25 - 0.50 0.25 - 0.50 LT 0.25
Tieton River - Darland Mt. LT 0.10 0.25 0.25 - 0.50 LT 0.10
Mt Hood Meadows LT 0.25 0.50 - 0.75 0.25 - 0.50 LT 0.10
Timberline LT 0.25 0.50 - 0.75 0.25 - 0.50 LT 0.10
Hurricane Ridge Precipitation (in)
Sunday Night LT 0.10
Monday 0.50
Monday Night 1.00 - 1.50
Tuesday LT 0.10
Mt Baker Ski Area Precipitation (in)
Sunday Night LT 0.25
Monday 1.00
Monday Night 2.00 - 2.50
Tuesday 0.50
Mt. Loop - Barlow Pass Precipitation (in)
Sunday Night LT 0.10
Monday 0.50 - 0.75
Monday Night 1.00 - 1.50
Tuesday LT 0.25
Stevens Pass Precipitation (in)
Sunday Night LT 0.10
Monday 0.25 - 0.50
Monday Night 0.50
Tuesday LT 0.25
Snoqualmie Pass Precipitation (in)
Sunday Night LT 0.10
Monday 0.50
Monday Night 0.25 - 0.50
Tuesday 0.25
Crystal Mt Precipitation (in)
Sunday Night LT 0.10
Monday 0.25
Monday Night 0.75
Tuesday LT 0.10
Paradise Precipitation (in)
Sunday Night LT 0.10
Monday 0.75 -1.00
Monday Night 1.00
Tuesday 0.25
White Pass Precipitation (in)
Sunday Night LT 0.10
Monday 0.25 - 0.50
Monday Night 0.25 - 0.50
Tuesday LT 0.25
Washington Pass Precipitation (in)
Sunday Night LT 0.10
Monday LT 0.10
Monday Night 0.25 - 0.50
Tuesday 0.25
Mission Ridge Precipitation (in)
Sunday Night 0
Monday 0.25
Monday Night 0.50
Tuesday LT 0.10
Salmon la Sac - Gallagher Head Precipitation (in)
Sunday Night LT 0.10
Monday 0.25 - 0.50
Monday Night 0.25 - 0.50
Tuesday LT 0.25
Tieton River - Darland Mt. Precipitation (in)
Sunday Night LT 0.10
Monday 0.25
Monday Night 0.25 - 0.50
Tuesday LT 0.10
Mt Hood Meadows Precipitation (in)
Sunday Night LT 0.25
Monday 0.50 - 0.75
Monday Night 0.25 - 0.50
Tuesday LT 0.10
Timberline Precipitation (in)
Sunday Night LT 0.25
Monday 0.50 - 0.75
Monday Night 0.25 - 0.50
Tuesday LT 0.10

Issued: 2:13 PM PST Sunday, December 24, 2023

Snow Level (ft)

Sunday Evening* Sunday Night* Monday Morning* Monday Afternoon* Monday Evening* Monday Night* Tuesday Morning* Tuesday Afternoon*
Olympics 5000' 2000' 5500' 7500' 7000' 5500' 4000' 3500'
West North 1000' 1000' 2000' 4500' 4500' 4000' 3000' 3000'
West Central 1000' 500' 1500' 4500' 4500' 4000' 3000' 3000'
West South 1500' 1500' 3000' 4000' 4000' 4500' 3500' 4000'
Stevens Pass 500' 0 500' 1000' 1500' 2000' 2000' 3500'
Snoqualmie Pass 500' 0 1000' 2000' 3000' 3000' 3000' 3500'
East North 0 0 0 1000' 1500' 1500' 1500' 3000'
East Central 500' 0 500' 1000' 2000' 2500' 2000' 3500'
East South 1000' 500' 1500' 2000' 3500' 3500' 4000' 4000'
Mt. Hood 2000' 2500' 3500' 3500' 4500' 5000' 4500' 5000'
Olympics Elevation
Sunday Evening* 5000'
Sunday Night* 2000'
Monday Morning* 5500'
Monday Afternoon* 7500'
Monday Evening* 7000'
Monday Night* 5500'
Tuesday Morning* 4000'
Tuesday Afternoon* 3500'
West North Elevation
Sunday Evening* 1000'
Sunday Night* 1000'
Monday Morning* 2000'
Monday Afternoon* 4500'
Monday Evening* 4500'
Monday Night* 4000'
Tuesday Morning* 3000'
Tuesday Afternoon* 3000'
West Central Elevation
Sunday Evening* 1000'
Sunday Night* 500'
Monday Morning* 1500'
Monday Afternoon* 4500'
Monday Evening* 4500'
Monday Night* 4000'
Tuesday Morning* 3000'
Tuesday Afternoon* 3000'
West South Elevation
Sunday Evening* 1500'
Sunday Night* 1500'
Monday Morning* 3000'
Monday Afternoon* 4000'
Monday Evening* 4000'
Monday Night* 4500'
Tuesday Morning* 3500'
Tuesday Afternoon* 4000'
Stevens Pass Elevation
Sunday Evening* 500'
Sunday Night* 0'
Monday Morning* 500'
Monday Afternoon* 1000'
Monday Evening* 1500'
Monday Night* 2000'
Tuesday Morning* 2000'
Tuesday Afternoon* 3500'
Snoqualmie Pass Elevation
Sunday Evening* 500'
Sunday Night* 0'
Monday Morning* 1000'
Monday Afternoon* 2000'
Monday Evening* 3000'
Monday Night* 3000'
Tuesday Morning* 3000'
Tuesday Afternoon* 3500'
East North Elevation
Sunday Evening* 0'
Sunday Night* 0'
Monday Morning* 0'
Monday Afternoon* 1000'
Monday Evening* 1500'
Monday Night* 1500'
Tuesday Morning* 1500'
Tuesday Afternoon* 3000'
East Central Elevation
Sunday Evening* 500'
Sunday Night* 0'
Monday Morning* 500'
Monday Afternoon* 1000'
Monday Evening* 2000'
Monday Night* 2500'
Tuesday Morning* 2000'
Tuesday Afternoon* 3500'
East South Elevation
Sunday Evening* 1000'
Sunday Night* 500'
Monday Morning* 1500'
Monday Afternoon* 2000'
Monday Evening* 3500'
Monday Night* 3500'
Tuesday Morning* 4000'
Tuesday Afternoon* 4000'
Mt. Hood Elevation
Sunday Evening* 2000'
Sunday Night* 2500'
Monday Morning* 3500'
Monday Afternoon* 3500'
Monday Evening* 4500'
Monday Night* 5000'
Tuesday Morning* 4500'
Tuesday Afternoon* 5000'

Issued: 2:13 PM PST Sunday, December 24, 2023

5000' Temperatures (°F)

Sunday Night Monday
Max / Min Max / Min
Olympics 30 / 27 38 / 33
West North 29 / 26 35 / 29
West Central 27 / 24 33 / 26
West South 30 / 27 35 / 30
Stevens Pass 22 / 19 27 / 20
Snoqualmie Pass 23 / 20 29 / 23
East North 17 / 14 23 / 16
East Central 22 / 20 29 / 22
East South 26 / 21 32 / 27
Mt. Hood 31 / 29 34 / 30
Olympics 5000' Temperature Forecast
(Max / Min)
Sunday Night 30 / 27
Monday 38 / 33
West North 5000' Temperature Forecast
(Max / Min)
Sunday Night 29 / 26
Monday 35 / 29
West Central 5000' Temperature Forecast
(Max / Min)
Sunday Night 27 / 24
Monday 33 / 26
West South 5000' Temperature Forecast
(Max / Min)
Sunday Night 30 / 27
Monday 35 / 30
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Sunday Night 22 / 19
Monday 27 / 20
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Sunday Night 23 / 20
Monday 29 / 23
East North 5000' Temperature Forecast
(Max / Min)
Sunday Night 17 / 14
Monday 23 / 16
East Central 5000' Temperature Forecast
(Max / Min)
Sunday Night 22 / 20
Monday 29 / 22
East South 5000' Temperature Forecast
(Max / Min)
Sunday Night 26 / 21
Monday 32 / 27
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Sunday Night 31 / 29
Monday 34 / 30

Issued: 2:13 PM PST Sunday, December 24, 2023

Ridgeline Winds (mph)

Sunday Evening Sunday Night Monday Morning Monday Afternoon
Olympics SSW 10-20 S 15-25 SSW 20-30 SSW 20-30
West North S 15-25 S 15-25 S 15-25 S 20-30
West Central S 5-15 SSE 10-20 SE 15-25 SE 15-25
West South SSW 5-15 S 5-15 SSE 5-15 S 5-15
Stevens Pass SSW 0-10 SSE 5-15 SE 10-20 SSE 10-20
Snoqualmie Pass SSE 10-20 SE 10-20 ESE 25-35 ESE 20-30
East North SSW 5-15 S 5-15 SSE 10-20 SSE 10-20
East Central WSW 10-20 SSW 10-20 S 15-25 S 15-25
East South WSW 5-15 S 5-15 SSE 5-15 S 5-15
Mt. Hood SW 15-25 SW 15-25 SW 20-30 SW 20-30
Olympics Ridgeline Winds (mph)
Sunday Evening SSW 10-20
Sunday Night S 15-25
Monday Morning SSW 20-30
Monday Afternoon SSW 20-30
West North Ridgeline Winds (mph)
Sunday Evening S 15-25
Sunday Night S 15-25
Monday Morning S 15-25
Monday Afternoon S 20-30
West Central Ridgeline Winds (mph)
Sunday Evening S 5-15
Sunday Night SSE 10-20
Monday Morning SE 15-25
Monday Afternoon SE 15-25
West South Ridgeline Winds (mph)
Sunday Evening SSW 5-15
Sunday Night S 5-15
Monday Morning SSE 5-15
Monday Afternoon S 5-15
Stevens Pass Ridgeline Winds (mph)
Sunday Evening SSW 0-10
Sunday Night SSE 5-15
Monday Morning SE 10-20
Monday Afternoon SSE 10-20
Snoqualmie Pass Ridgeline Winds (mph)
Sunday Evening SSE 10-20
Sunday Night SE 10-20
Monday Morning ESE 25-35
Monday Afternoon ESE 20-30
East North Ridgeline Winds (mph)
Sunday Evening SSW 5-15
Sunday Night S 5-15
Monday Morning SSE 10-20
Monday Afternoon SSE 10-20
East Central Ridgeline Winds (mph)
Sunday Evening WSW 10-20
Sunday Night SSW 10-20
Monday Morning S 15-25
Monday Afternoon S 15-25
East South Ridgeline Winds (mph)
Sunday Evening WSW 5-15
Sunday Night S 5-15
Monday Morning SSE 5-15
Monday Afternoon S 5-15
Mt. Hood Ridgeline Winds (mph)
Sunday Evening SW 15-25
Sunday Night SW 15-25
Monday Morning SW 20-30
Monday Afternoon SW 20-30

Issued: 2:13 PM PST Sunday, December 24, 2023

Extended Weather Synopsis

Tuesday night brings a relative break in the action with continued moderate southerly winds and E winds increasing once again. Light to moderate pulses of rain and snow arrive through Wednesday night with the E slopes and passes remaining mostly frozen precipitation. Another system offshore winds up with precipitation mostly impacting the Olympics and Baker areas on Thursday.

Extended Snow Level (ft)

Tuesday Night* Wednesday * Wednesday Night* Thursday *
West North 3000' 4000' 3500' 3500'
Snoqualmie Pass 3000' 3000' 3000' 3000'
Mt. Hood 5000' 4500' 5000' 5000'
West North Elevation
Tuesday Night* 3000'
Wednesday * 4000'
Wednesday Night* 3500'
Thursday * 3500'
Snoqualmie Pass Elevation
Tuesday Night* 3000'
Wednesday * 3000'
Wednesday Night* 3000'
Thursday * 3000'
Mt. Hood Elevation
Tuesday Night* 5000'
Wednesday * 4500'
Wednesday Night* 5000'
Thursday * 5000'

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

Previous forecast from Dec 24, 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’.