Issued: 7:09 AM PST Tuesday, February 23, 2021
by Dennis D'Amico

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

Weather Synopsis

We'll remain in cool NW flow today with an upper-level feature enhancing shower activity and winds in the afternoon. Mountain temperatures have dropped precipitously following the passage of a frontal boundary and atmospheric river event overnight. Snow levels this morning are between 1500-2000' and upper mountain station temperatures have plummeted into the teens. Along with scattered showers this morning, convergence zone activity will be focused into the central Cascades today, first around the Mountain Loop to Snoqualmie Pass area and then focusing more on the I-90 corridor in the afternoon and early evening.  Shower activity will increase for all areas this afternoon. Westerly ridgeline winds will be strong for most areas today, pushing to extreme along the central and south east slopes of the Cascades and in alpine areas south of Mt Rainier to Mt Hood. 

The flow will begin to turn northerly tonight, cutting off the shower activity from north to south.  A clearing trend will begin later tonight with upper-level ridging building offshore. Tomorrow should be partly to mostly sunny with much lighter winds and cool freezing levels for late February. High clouds will begin to create filtered sunshine in the afternoon as the next Pacific frontal system in NW flow aloft approaches. 

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
Tuesday Mostly cloudy with scattered light snow showers becoming cloudy with light to occasionally moderate snow showers in the afternoon. Increasing ridgeline winds.
Tuesday Night Mostly cloudy in the evening with isolated light snow showers becoming partly cloudy overnight.
Tuesday Mostly cloudy with scattered light snow showers becoming cloudy with light to moderate snow showers in the afternoon. Increasing ridgeline winds.
Tuesday Night Mostly cloudy in the evening with scattered light snow showers becoming partly cloudy overnight.
Tuesday Cloudy with moderate snow showers. Strong ridgeline winds.
Tuesday Night Cloudy in the evening with scattered light to occasionally moderate snow showers becoming partly cloudy overnight. Ridgeline winds decreasing overnight.
Tuesday Cloudy with light to occasionally moderate snow showers increasing to moderate in the afternoon. Heaviest showers Paradise and White Pass areas. Strong ridgeline winds.
Tuesday Night Cloudy in the evening light to occasionally moderate snow showers becoming mostly cloudy late. Ridgeline winds decreasing overnight.
Tuesday Cloudy with moderate snow showers. Strong west wind at ridgeline and Pass level.
Tuesday Night Cloudy in the evening with scattered light to occasionally moderate snow showers becoming partly cloudy overnight. Ridgeline and Pass winds decreasing overnight.
Tuesday Cloudy with light to moderate snow showers in the morning increasing to moderate to occasionally heavy in the afternoon. Strong west wind at ridgeline and Pass level.
Tuesday Night Cloudy in the evening with light to moderate snow showers becoming mostly cloudy late. Ridgeline and Pass winds decreasing overnight.
Tuesday Cloudy with scattered light snow showers in the morning increasing to light to occasionally moderate in the afternoon. Strong ridgeline winds decreasing in the afternoon.
Tuesday Night Mostly cloudy in the evening with scattered light snow showers becoming partly cloudy overnight.
Tuesday Cloudy with light snow showers, occasionally moderate near the Cascade crest in the morning increasing in the afternoon. Strong to extreme ridgeline winds.
Tuesday Night Cloudy in the evening with light snow showers, occasionally moderate near the Cascade crest, becoming partly cloudy overnight. Ridgeline winds decreasing overnight.
Tuesday Cloudy with light snow showers, occasionally moderate near the Cascade crest in the morning increasing in the afternoon. Strong to extreme ridgeline winds.
Tuesday Night Cloudy in the evening with light snow showers, occasionally moderate near the Cascade crest, becoming partly cloudy overnight. Ridgeline winds decreasing overnight.
Tuesday Mostly cloudy with scattered light rain and snow showers in the morning, becoming cloudy with light to occasionally moderate snow showers in the afternoon. Fewer clouds east-side of the mountain. Strong to extreme winds.
Tuesday Night Cloudy in the evening with light to moderate snow showers, becoming mostly cloudy late. Ridgeline winds decreasing overnight.

Precipitation (in)

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

Snow Level (ft)

Tuesday Morning Tuesday Afternoon Tuesday Evening Tuesday Night Wednesday Morning Wednesday Afternoon
Olympics 2000' 2000' 1500' 500' 1500' 2500'
West North 1500' 1500' 1000' 0 1500' 2500'
West Central 1500' 2000' 1000' 0 1500' 3000'
West South 2000' 2500' 1000' 0 1500' 3500'
Stevens Pass 1500' 2000' 1000' 0 1500' 3000'
Snoqualmie Pass 2000' 2000' 1000' 0 1500' 3000'
East North 2000' 2000' 1000' 0 1500' 3000'
East Central 2000' 2000' 1000' 0 1500' 3500'
East South 2000' 2000' 1000' 0 1500' 3500'
Mt. Hood 2500' 2500' 1500' 1000' 1500' 3500'
Olympics Elevation
Tuesday Morning 2000'
Tuesday Afternoon 2000'
Tuesday Evening 1500'
Tuesday Night 500'
Wednesday Morning 1500'
Wednesday Afternoon 2500'
West North Elevation
Tuesday Morning 1500'
Tuesday Afternoon 1500'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 2500'
West Central Elevation
Tuesday Morning 1500'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3000'
West South Elevation
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3500'
Stevens Pass Elevation
Tuesday Morning 1500'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3000'
Snoqualmie Pass Elevation
Tuesday Morning 2000'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3000'
East North Elevation
Tuesday Morning 2000'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3000'
East Central Elevation
Tuesday Morning 2000'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3500'
East South Elevation
Tuesday Morning 2000'
Tuesday Afternoon 2000'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 3500'
Mt. Hood Elevation
Tuesday Morning 2500'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 3500'

5000' Temperatures (°F)

Tuesday Tuesday Night
Max / Min Max / Min
Olympics 22 / 19 18 / 10
West North 21 / 17 18 / 11
West Central 21 / 19 19 / 11
West South 23 / 20 21 / 12
Stevens Pass 23 / 19 19 / 12
Snoqualmie Pass 22 / 18 19 / 14
East North 23 / 14 17 / 11
East Central 23 / 17 18 / 11
East South 24 / 18 21 / 12
Mt. Hood 25 / 19 23 / 14
Olympics 5000' Temperature Forecast
(Max / Min)
Tuesday 22 / 19
Tuesday Night 18 / 10
West North 5000' Temperature Forecast
(Max / Min)
Tuesday 21 / 17
Tuesday Night 18 / 11
West Central 5000' Temperature Forecast
(Max / Min)
Tuesday 21 / 19
Tuesday Night 19 / 11
West South 5000' Temperature Forecast
(Max / Min)
Tuesday 23 / 20
Tuesday Night 21 / 12
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Tuesday 23 / 19
Tuesday Night 19 / 12
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Tuesday 22 / 18
Tuesday Night 19 / 14
East North 5000' Temperature Forecast
(Max / Min)
Tuesday 23 / 14
Tuesday Night 17 / 11
East Central 5000' Temperature Forecast
(Max / Min)
Tuesday 23 / 17
Tuesday Night 18 / 11
East South 5000' Temperature Forecast
(Max / Min)
Tuesday 24 / 18
Tuesday Night 21 / 12
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Tuesday 25 / 19
Tuesday Night 23 / 14

Ridgeline Winds (mph)

Tuesday Morning Tuesday Afternoon Tuesday Evening Tuesday Night
Olympics W 15-25 W 20-30 WNW 10-20 N 0-10
West North W 10-20 W 15-25 WNW 5-15 NNE 0-10
West Central W 20-30 W 20-30 NW 15-25 NW 5-15
West South W 20-30 W 25-35 WNW 20-30 NW 5-15
Stevens Pass W 20-30 W 20-30 WNW 15-25 NW 5-15
Snoqualmie Pass W 20-30 W 25-35 WNW 20-30 NW 10-20
East North WNW 25-35 W 15-25 WNW 15-25 NNW 10-20
East Central W 30-40 W 35-50 WNW 25-35 NW 10-20
East South W 30-40 W 30-40 WNW 20-30 WNW 10-20
Mt. Hood W 20-30 W 30-40 W 30-40 NW 20-30
Olympics Ridgeline Winds (mph)
Tuesday Morning W 15-25
Tuesday Afternoon W 20-30
Tuesday Evening WNW 10-20
Tuesday Night N 0-10
West North Ridgeline Winds (mph)
Tuesday Morning W 10-20
Tuesday Afternoon W 15-25
Tuesday Evening WNW 5-15
Tuesday Night NNE 0-10
West Central Ridgeline Winds (mph)
Tuesday Morning W 20-30
Tuesday Afternoon W 20-30
Tuesday Evening NW 15-25
Tuesday Night NW 5-15
West South Ridgeline Winds (mph)
Tuesday Morning W 20-30
Tuesday Afternoon W 25-35
Tuesday Evening WNW 20-30
Tuesday Night NW 5-15
Stevens Pass Ridgeline Winds (mph)
Tuesday Morning W 20-30
Tuesday Afternoon W 20-30
Tuesday Evening WNW 15-25
Tuesday Night NW 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Tuesday Morning W 20-30
Tuesday Afternoon W 25-35
Tuesday Evening WNW 20-30
Tuesday Night NW 10-20
East North Ridgeline Winds (mph)
Tuesday Morning WNW 25-35
Tuesday Afternoon W 15-25
Tuesday Evening WNW 15-25
Tuesday Night NNW 10-20
East Central Ridgeline Winds (mph)
Tuesday Morning W 30-40
Tuesday Afternoon W 35-50
Tuesday Evening WNW 25-35
Tuesday Night NW 10-20
East South Ridgeline Winds (mph)
Tuesday Morning W 30-40
Tuesday Afternoon W 30-40
Tuesday Evening WNW 20-30
Tuesday Night WNW 10-20
Mt. Hood Ridgeline Winds (mph)
Tuesday Morning W 20-30
Tuesday Afternoon W 30-40
Tuesday Evening W 30-40
Tuesday Night NW 20-30

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

Previous forecast from Feb 22, 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’.