Issued: 2:23 PM PST Monday, February 13, 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 cold, unstable fetch of post-frontal WNW flow continues Monday night. WNW flow will be strongest in the southern half of the Cascades and along the E slopes. These winds should remain in the moderate to strong range in many areas through the evening hours, but ease overnight. Shower activity and convergence (focused on the central Washington Cascades) picks up in the evening hours ahead of an upper low sliding down the coast, but this feature will ultimately cut off westerly flow from north to south. Convergence may shift between areas from just south of Snoqualmie Pass to just north of Stevens Pass before relenting overnight along with overall shower activity.The models seem to have the bulls-eye on Snoqualmie Pass, which could pick up 6-12" of snow overnight. Similar amounts of additional snow can be expected at Mt. Hood and Paradise, with 4-8" amounts for Stevens Pass and the southern Mountain Loop. Snow levels drop from below 2000 ft to near sea level, yielding high snow ratios.

Snow showers wind down very early Tuesday, with sunny skies expected across the region by the afternoon as an offshore ridge of high pressure works into the region. It will be a chilly day with freezing levels rising only to 1500-2500 ft by the afternoon.

Light N flow continues Tuesday night into Wednesday with clear weather and light winds contributing to a very chilly start to the day, particularly in deep valley locations. The ridge axis works into the region by the afternoon. Expect mostly sunny skies with high clouds moving in from the west associated with a stalled frontal system offshore.

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
Monday Night Light snow showers.
Tuesday A few snow flurries early in the northern Olympics with light upslope flow.
Monday Night Decreasing light snow showers ending by morning.
Tuesday Gradual clearing.
Monday Night Moderate snow showers (heavy southern part) and convergence in the evening, becoming light to moderate overnight.
Tuesday A few flurries early, then gradual clearing.
Monday Night Moderate to heavy snow showers in the evening (light to moderate at Crystal and White Pass), then becoming light overnight.
Tuesday A few flurries early, then gradual clearing.
Monday Night Moderate snow showers and convergence in the evening, becoming light overnight. Decreasing light to moderate ridgeline and W wind at the Pass.
Tuesday A few flurries early, then gradual clearing.
Monday Night Moderate to heavy snow showers and convergence in the evening, becoming light overnight. Decreasing moderate ridgeline and light to moderate W wind at the Pass.
Tuesday A few flurries early, then gradual clearing.
Monday Night Light snow showers tapering in the evening, with mostly cloudy skies overnight.
Tuesday Rapidly clearing skies.
Monday Night Light snow showers (moderate in convergence spillover) decreasing overnight. Moderate ridgeline winds decreasing overnight.
Tuesday Rapidly clearing skies.
Monday Night Decreasing light snow showers. Moderate ridgeline winds decreasing overnight.
Tuesday Rapidly clearing skies.
Monday Night Heavy snow showers becoming moderate overnight. Strong ridgeline winds decreasing in the early morning hours.
Tuesday Light snow showers early, then clearing skies in the afternoon.

Issued: 2:23 PM PST Monday, February 13, 2023

Precipitation (in)

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

Issued: 2:23 PM PST Monday, February 13, 2023

Snow Level (ft)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon Tuesday Evening Tuesday Night Wednesday Morning Wednesday Afternoon
Olympics 1000' 0 500' 2000' 2000' 1000' 1000' 2500'
West North 1000' 0 0 2000' 2000' 500' 500' 2000'
West Central 1000' 0 0 1500' 1500' 500' 500' 2000'
West South 1000' 0 0 2000' 1500' 500' 500' 2500'
Stevens Pass 1000' 0 0 1500' 2000' 500' 500' 2000'
Snoqualmie Pass 1000' 0 0 1500' 1500' 500' 500' 2500'
East North 500' 0 0 2500' 2000' 500' 0 2500'
East Central 1000' 0 0 2500' 2000' 1000' 500' 2500'
East South 1000' 0 500' 2500' 2000' 1000' 1000' 3000'
Mt. Hood 1000' 0 0 2000' 2000' 1000' 1000' 3000'
Olympics Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 500'
Tuesday Afternoon 2000'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1000'
Wednesday Afternoon 2500'
West North Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 2000'
Tuesday Evening 2000'
Tuesday Night 500'
Wednesday Morning 500'
Wednesday Afternoon 2000'
West Central Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 1500'
Tuesday Evening 1500'
Tuesday Night 500'
Wednesday Morning 500'
Wednesday Afternoon 2000'
West South Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 2000'
Tuesday Evening 1500'
Tuesday Night 500'
Wednesday Morning 500'
Wednesday Afternoon 2500'
Stevens Pass Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 1500'
Tuesday Evening 2000'
Tuesday Night 500'
Wednesday Morning 500'
Wednesday Afternoon 2000'
Snoqualmie Pass Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 1500'
Tuesday Evening 1500'
Tuesday Night 500'
Wednesday Morning 500'
Wednesday Afternoon 2500'
East North Elevation
Monday Evening 500'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 500'
Wednesday Morning 0'
Wednesday Afternoon 2500'
East Central Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 500'
Wednesday Afternoon 2500'
East South Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 500'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1000'
Wednesday Afternoon 3000'
Mt. Hood Elevation
Monday Evening 1000'
Monday Night 0'
Tuesday Morning 0'
Tuesday Afternoon 2000'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1000'
Wednesday Afternoon 3000'

Issued: 2:23 PM PST Monday, February 13, 2023

5000' Temperatures (°F)

Monday Night Tuesday
Max / Min Max / Min
Olympics 22 / 12 26 / 10
West North 23 / 11 26 / 10
West Central 23 / 11 26 / 10
West South 23 / 14 27 / 10
Stevens Pass 23 / 12 27 / 10
Snoqualmie Pass 23 / 14 26 / 11
East North 18 / 11 25 / 10
East Central 22 / 12 27 / 12
East South 23 / 15 28 / 12
Mt. Hood 24 / 17 26 / 15
Olympics 5000' Temperature Forecast
(Max / Min)
Monday Night 22 / 12
Tuesday 26 / 10
West North 5000' Temperature Forecast
(Max / Min)
Monday Night 23 / 11
Tuesday 26 / 10
West Central 5000' Temperature Forecast
(Max / Min)
Monday Night 23 / 11
Tuesday 26 / 10
West South 5000' Temperature Forecast
(Max / Min)
Monday Night 23 / 14
Tuesday 27 / 10
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 23 / 12
Tuesday 27 / 10
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 23 / 14
Tuesday 26 / 11
East North 5000' Temperature Forecast
(Max / Min)
Monday Night 18 / 11
Tuesday 25 / 10
East Central 5000' Temperature Forecast
(Max / Min)
Monday Night 22 / 12
Tuesday 27 / 12
East South 5000' Temperature Forecast
(Max / Min)
Monday Night 23 / 15
Tuesday 28 / 12
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday Night 24 / 17
Tuesday 26 / 15

Issued: 2:23 PM PST Monday, February 13, 2023

Ridgeline Winds (mph)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon
Olympics WNW 15-25 NNW 0-10 N 0-10 NNE 0-10
West North W 15-25 W 5-15 NNE 5-15 N 0-10
West Central WNW 15-25 NW 10-20 N 5-15 NW 0-10
West South WNW 20-30 WNW 10-20 NNW 5-15 NNW 0-10
Stevens Pass WNW 15-25 NW 10-20 NW 0-10 WNW 0-10
Snoqualmie Pass NW 20-30 WNW 15-25 NNW 5-15 NW 0-10
East North W 10-20 WNW 10-20 NNW 5-15 NW 5-15
East Central WNW 20-30 WNW 15-25 NNW 5-15 NNW 0-10
East South WNW 20-30 WNW 10-20 NNW 5-15 N 0-10
Mt. Hood WNW 30-40 WNW 20-30 WNW 10-20 N 0-10
Olympics Ridgeline Winds (mph)
Monday Evening WNW 15-25
Monday Night NNW 0-10
Tuesday Morning N 0-10
Tuesday Afternoon NNE 0-10
West North Ridgeline Winds (mph)
Monday Evening W 15-25
Monday Night W 5-15
Tuesday Morning NNE 5-15
Tuesday Afternoon N 0-10
West Central Ridgeline Winds (mph)
Monday Evening WNW 15-25
Monday Night NW 10-20
Tuesday Morning N 5-15
Tuesday Afternoon NW 0-10
West South Ridgeline Winds (mph)
Monday Evening WNW 20-30
Monday Night WNW 10-20
Tuesday Morning NNW 5-15
Tuesday Afternoon NNW 0-10
Stevens Pass Ridgeline Winds (mph)
Monday Evening WNW 15-25
Monday Night NW 10-20
Tuesday Morning NW 0-10
Tuesday Afternoon WNW 0-10
Snoqualmie Pass Ridgeline Winds (mph)
Monday Evening NW 20-30
Monday Night WNW 15-25
Tuesday Morning NNW 5-15
Tuesday Afternoon NW 0-10
East North Ridgeline Winds (mph)
Monday Evening W 10-20
Monday Night WNW 10-20
Tuesday Morning NNW 5-15
Tuesday Afternoon NW 5-15
East Central Ridgeline Winds (mph)
Monday Evening WNW 20-30
Monday Night WNW 15-25
Tuesday Morning NNW 5-15
Tuesday Afternoon NNW 0-10
East South Ridgeline Winds (mph)
Monday Evening WNW 20-30
Monday Night WNW 10-20
Tuesday Morning NNW 5-15
Tuesday Afternoon N 0-10
Mt. Hood Ridgeline Winds (mph)
Monday Evening WNW 30-40
Monday Night WNW 20-30
Tuesday Morning WNW 10-20
Tuesday Afternoon N 0-10

Issued: 2:23 PM PST Monday, February 13, 2023

Extended Weather Synopsis

The stalled front splits and with a subtle trough brushing NW Washington with some light snow showers Thursday on SW flow. The weak trough should pass over the area early Friday with light snow or weak convergence for the west slopes of the Cascades. Temperatures should be near seasonal norms.

Extended Snow Level (ft)

Wednesday Night* Thursday * Thursday Night Friday
West North 1000' 1500' 1500' 2000'
Snoqualmie Pass 1500' 2500' 3000' 2500'
Mt. Hood 2500' 3500' 3000' 3000'
West North Elevation
Wednesday Night* 1000'
Thursday * 1500'
Thursday Night 1500'
Friday 2000'
Snoqualmie Pass Elevation
Wednesday Night* 1500'
Thursday * 2500'
Thursday Night 3000'
Friday 2500'
Mt. Hood Elevation
Wednesday Night* 2500'
Thursday * 3500'
Thursday Night 3000'
Friday 3000'

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

Previous forecast from Feb 13, 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’.