Issued: 7:06 AM PDT Monday, March 22, 2021
by Dennis D'Amico

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

Weather Synopsis

A front passed through the Cascades in the early morning hours, producing about 6-15 inches of snow along the west slopes of the Cascades and Mt Hood with lighter amounts along the east slopes and Olymipcs.  Showers will continue in earnest this morning with additional accumulations especially for the Mt Hood area and near a convergence zone currently along Hwy 2. The convergence zone should shift south later this morning towards the I-90 corridor and eventually down into the Crystal and Mt Rainier area by mid-day. A cool upper trough passing east of the Cascades will keep conditions cool, showery and cloudy elsewhere. Strong post-front west winds will slowly ease this afternoon and start to turn more northwesterly. 

We should dry out heading into tomorrow morning as strong upper level ridging builds offshore.  However, the ridge will quickly buckle on Tuesday, allowing high clouds to stream over much of Washington state and trapping low clouds from about Snoqualmie Pass and northward along the west slopes of the Cascades. Clearer conditions are likely south of I-90 to Mt. Hood on Tuesday. 

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 Partly to mostly cloudy with scattered light rain and snow showers.
Monday Night Partly to mostly cloudy.
Monday Cloudy with light rain and snow showers in the morning, becoming mostly cloudy with scattered light rain and snow showers in the afternoon.
Monday Night Mostly cloudy.
Monday Cloudy with light to occasionally moderate rain and snow showers in the morning. Light scattered showers in the afternoon.
Monday Night Partly to mostly cloudy.
Monday Mostly cloudy with scattered light rain and snow showers in the morning, becoming cloudy with light to occasionally moderate showers in the afternoon. Strong ridgeline winds decreasing in the afternoon.
Monday Night Mostly cloudy with scattered light showers in the evening ending after midnight.
Monday Cloudy with light to occasionally moderate rain and snow showers in the morning. Light scattered showers in the afternoon. Moderate to strong ridgeline and Pass level west winds decreasing in the afternoon.
Monday Night Partly to mostly cloudy.
Monday Cloudy with light to occasionally moderate rain and snow showers in the morning. Light scattered showers in the afternoon. Strong ridgeline and Pass level west winds decreasing in the afternoon.
Monday Night Partly to mostly cloudy. Chance of light showers in the evening.
Monday Cloudy with scattered light rain and snow showers in the morning, becoming mostly cloudy with isolated showers in the afternoon.
Monday Night Partly cloudy.
Monday Cloudy with light rain and snow showers in the morning, occasionally moderate near the Cascade crest. Mostly to partly cloudy with isolated light showers in the afternoon. Strong ridgeline winds.
Monday Night Partly to mostly clear.
Monday Cloudy with light rain and snow showers in the morning, occasionally moderate near the Cascade crest. Mostly to partly cloudy with isolated light showers in the afternoon. Strong ridgeline winds.
Monday Night Partly to mostly clear.
Monday Cloudy with light to moderate rain and snow showers in the morning, becoming mostly cloudy with scattered light showers in the afternoon. More sunbreaks east side of the mountain. Strong ridgeline winds.
Monday Night Mostly cloudy with scattered light showers in the evening ending after midnight.

Precipitation (in)

Monday Monday Night Tuesday
5 am - 5 pm 5 pm - 5 am 5 am - 5 pm
Hurricane Ridge LT 0.25 LT 0.10 0
Mt Baker Ski Area LT 0.25 0 0
Mt. Loop - Barlow Pass 0.25 0 0
Stevens Pass LT 0.25 0 0
Snoqualmie Pass 0.25 - 0.50 LT 0.10 0
Crystal Mt 0.25 - 0.50 LT 0.10 0
Paradise 0.25 - 0.50 LT 0.10 0
White Pass LT 0.25 LT 0.10 0
Washington Pass LT 0.10 0 0
Mission Ridge 0 0 0
Salmon la Sac - Gallagher Head LT 0.25 0 0
Tieton River - Darland Mt. LT 0.10 0 0
Mt Hood Meadows 0.50 LT 0.10 0
Timberline 0.50 - 0.75 LT 0.10 0
Hurricane Ridge Precipitation (in)
Monday LT 0.25
Monday Night LT 0.10
Tuesday 0
Mt Baker Ski Area Precipitation (in)
Monday LT 0.25
Monday Night 0
Tuesday 0
Mt. Loop - Barlow Pass Precipitation (in)
Monday 0.25
Monday Night 0
Tuesday 0
Stevens Pass Precipitation (in)
Monday LT 0.25
Monday Night 0
Tuesday 0
Snoqualmie Pass Precipitation (in)
Monday 0.25 - 0.50
Monday Night LT 0.10
Tuesday 0
Crystal Mt Precipitation (in)
Monday 0.25 - 0.50
Monday Night LT 0.10
Tuesday 0
Paradise Precipitation (in)
Monday 0.25 - 0.50
Monday Night LT 0.10
Tuesday 0
White Pass Precipitation (in)
Monday LT 0.25
Monday Night LT 0.10
Tuesday 0
Washington Pass Precipitation (in)
Monday LT 0.10
Monday Night 0
Tuesday 0
Mission Ridge Precipitation (in)
Monday 0
Monday Night 0
Tuesday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Monday LT 0.25
Monday Night 0
Tuesday 0
Tieton River - Darland Mt. Precipitation (in)
Monday LT 0.10
Monday Night 0
Tuesday 0
Mt Hood Meadows Precipitation (in)
Monday 0.50
Monday Night LT 0.10
Tuesday 0
Timberline Precipitation (in)
Monday 0.50 - 0.75
Monday Night LT 0.10
Tuesday 0

Snow Level (ft)

Monday Morning Monday Afternoon Monday Evening Monday Night Tuesday Morning Tuesday Afternoon
Olympics 2000' 3500' 2500' 2000' 2500' 4000'
West North 2000' 3000' 2000' 1000' 2500' 3500'
West Central 2500' 3000' 2000' 1500' 2500' 3500'
West South 2500' 3500' 2000' 1500' 2500' 3500'
Stevens Pass 2500' 3000' 2000' 1500' 2500' 3500'
Snoqualmie Pass 2500' 3000' 2000' 1500' 2500' 4000'
East North 2500' 4000' 2000' 1000' 2500' 4000'
East Central 3000' 4500' 3000' 2000' 2500' 4500'
East South 3000' 4500' 3000' 2000' 2500' 4500'
Mt. Hood 3500' 3500' 3000' 2500' 2500' 4000'
Olympics Elevation
Monday Morning 2000'
Monday Afternoon 3500'
Monday Evening 2500'
Monday Night 2000'
Tuesday Morning 2500'
Tuesday Afternoon 4000'
West North Elevation
Monday Morning 2000'
Monday Afternoon 3000'
Monday Evening 2000'
Monday Night 1000'
Tuesday Morning 2500'
Tuesday Afternoon 3500'
West Central Elevation
Monday Morning 2500'
Monday Afternoon 3000'
Monday Evening 2000'
Monday Night 1500'
Tuesday Morning 2500'
Tuesday Afternoon 3500'
West South Elevation
Monday Morning 2500'
Monday Afternoon 3500'
Monday Evening 2000'
Monday Night 1500'
Tuesday Morning 2500'
Tuesday Afternoon 3500'
Stevens Pass Elevation
Monday Morning 2500'
Monday Afternoon 3000'
Monday Evening 2000'
Monday Night 1500'
Tuesday Morning 2500'
Tuesday Afternoon 3500'
Snoqualmie Pass Elevation
Monday Morning 2500'
Monday Afternoon 3000'
Monday Evening 2000'
Monday Night 1500'
Tuesday Morning 2500'
Tuesday Afternoon 4000'
East North Elevation
Monday Morning 2500'
Monday Afternoon 4000'
Monday Evening 2000'
Monday Night 1000'
Tuesday Morning 2500'
Tuesday Afternoon 4000'
East Central Elevation
Monday Morning 3000'
Monday Afternoon 4500'
Monday Evening 3000'
Monday Night 2000'
Tuesday Morning 2500'
Tuesday Afternoon 4500'
East South Elevation
Monday Morning 3000'
Monday Afternoon 4500'
Monday Evening 3000'
Monday Night 2000'
Tuesday Morning 2500'
Tuesday Afternoon 4500'
Mt. Hood Elevation
Monday Morning 3500'
Monday Afternoon 3500'
Monday Evening 3000'
Monday Night 2500'
Tuesday Morning 2500'
Tuesday Afternoon 4000'

5000' Temperatures (°F)

Monday Monday Night
Max / Min Max / Min
Olympics 32 / 24 25 / 19
West North 30 / 23 23 / 17
West Central 28 / 24 23 / 17
West South 29 / 23 25 / 16
Stevens Pass 28 / 24 24 / 17
Snoqualmie Pass 29 / 24 23 / 17
East North 31 / 22 25 / 17
East Central 32 / 25 23 / 18
East South 32 / 25 25 / 19
Mt. Hood 30 / 27 25 / 20
Olympics 5000' Temperature Forecast
(Max / Min)
Monday 32 / 24
Monday Night 25 / 19
West North 5000' Temperature Forecast
(Max / Min)
Monday 30 / 23
Monday Night 23 / 17
West Central 5000' Temperature Forecast
(Max / Min)
Monday 28 / 24
Monday Night 23 / 17
West South 5000' Temperature Forecast
(Max / Min)
Monday 29 / 23
Monday Night 25 / 16
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday 28 / 24
Monday Night 24 / 17
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday 29 / 24
Monday Night 23 / 17
East North 5000' Temperature Forecast
(Max / Min)
Monday 31 / 22
Monday Night 25 / 17
East Central 5000' Temperature Forecast
(Max / Min)
Monday 32 / 25
Monday Night 23 / 18
East South 5000' Temperature Forecast
(Max / Min)
Monday 32 / 25
Monday Night 25 / 19
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday 30 / 27
Monday Night 25 / 20

Ridgeline Winds (mph)

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

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

Previous forecast from Mar 21, 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’.