Issued: 2:30 PM PDT Wednesday, April 7, 2021
by Dennis D'Amico

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

Weather Synopsis

A Pacific frontal system sagging south over the region this afternoon will pass through the Cascades between 12 am-2 am tonight. Behind the front, a Puget Sound Convergence zone will form, targeting the Mt Loop to Hwy2 corridor with the heaviest showers before sliding south towards Snoqualmie Pass round daybreak. Light to moderate showers in westerly post-frontal flow will impact the rest of the west slopes of the Cascades and Mt. Hood. Look for strong ridgeline winds, approaching extreme near Mt Hood tonight along with a sharp drop in snow levels. Look for 4-12" from this system through Thursday morning along the west slopes of the Cascades and Mt Hood area. 

Showers will begin to peter out by late morning or mid-day tomorrow. Shortwave ridging moving overhead and continued onshore flow should help lock in cloud cover for most of the mountains tomorrow. 

A system will a similar track and timing will begin to move into the Olympics and north Cascades on Friday afternoon, with increasing cloud cover over the south Cascades and Mt. Hood.  

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
Wednesday Night Moderate rain and snow becoming light to moderate snow showers after midnight. Strong ridgeline winds decreasing after midnight.
Thursday Partly cloudy in the morning becoming mostly cloudy in the afternoon. Chance of rain or snow showers.
Wednesday Night Moderate rain and snow becoming light to moderate snow showers after midnight. Strong ridgeline winds decreasing after midnight.
Thursday Cloudy with light to occasionally moderate snow showers in the morning, becoming mostly cloudy with scattered light showers mid-day.
Wednesday Night Moderate rain and snow becoming moderate showers after midnight. Strong ridgeline winds.
Thursday Cloudy with light to moderate snow showers in the morning, becoming scattered light showers mid-day. A few sunbreaks possible.
Wednesday Night Light to moderate rain and snow becoming light to moderate showers after midnight. Heaviest precipitation Paradise area. Strong ridgeline winds.
Thursday Cloudy with light to occasionally moderate snow showers in the morning, becoming mostly cloudy with scattered light showers mid-day.
Wednesday Night Light to moderate rain and snow becoming moderate showers after midnight. Strong ridgeline and Pass level winds.
Thursday Cloudy with light to occasionally moderate snow showers in the morning, becoming scattered light showers mid-day. Sunbreaks possible in the afternoon.
Wednesday Night Light to moderate rain and snow becoming moderate showers after midnight. Strong ridgeline and Pass level winds.
Thursday Moderate snow showers in the morning, becoming scattered light showers mid-day. Sunbreaks possible in the afternoon.
Wednesday Night Light to moderate rain and snow becoming light to occasionally modearte showers after midnight. Strong ridgeline winds decreasing after midnight.
Thursday Cloudy with light to occasionally moderate snow showers in the morning, becoming scattered light showers mid-day. Sunbreaks possible in the afternoon.
Wednesday Night Light to occasionally moderate rain and snow becoming showers after midnight. Heaviest showers near the Cascade crest. Strong ridgeline winds.
Thursday Mostly cloudy with light to occasionally moderate snow showers in the morning, becoming partly to mostly cloudy in the afternoon. Heaviest showers near the Cascade crest.
Wednesday Night Light to occasionally moderate rain and snow becoming light showers after midnight. Strong ridgeline winds.
Thursday Mostly cloudy with light snow showers in the morning, becoming partly to mostly cloudy in the afternoon.
Wednesday Night Light to moderate rain and snow becoming moderate after midnight. Strong to extreme winds.
Thursday Mostly cloudy with light to occasionally moderate snow showers in the morning, becoming partly to mostly cloudy in the afternoon. More sunbreaks east-side and in the alpine.

Precipitation (in)

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

Snow Level (ft)

Wednesday Evening Wednesday Night Thursday Morning Thursday Afternoon Thursday Evening Thursday Night Friday Morning Friday Afternoon
Olympics 2500' 1500' 2000' 3000' 2000' 1500' 2000' 3000'
West North 2500' 2000' 1500' 3000' 2000' 1500' 2000' 2500'
West Central 2500' 2000' 1500' 3000' 2000' 1500' 2500' 3500'
West South 3500' 2500' 1500' 3500' 2500' 1500' 3000' 4000'
Stevens Pass 3000' 2000' 1500' 3000' 2000' 1500' 2500' 3500'
Snoqualmie Pass 3000' 2000' 1500' 3000' 2000' 1500' 2500' 3500'
East North 3500' 2000' 2000' 3500' 2500' 1500' 3000' 4000'
East Central 3500' 2500' 2000' 3500' 2500' 1500' 3000' 4500'
East South 3500' 2500' 2500' 3500' 2500' 1500' 3000' 4500'
Mt. Hood 4000' 3500' 2500' 3500' 2500' 2500' 3500' 5000'
Olympics Elevation
Wednesday Evening 2500'
Wednesday Night 1500'
Thursday Morning 2000'
Thursday Afternoon 3000'
Thursday Evening 2000'
Thursday Night 1500'
Friday Morning 2000'
Friday Afternoon 3000'
West North Elevation
Wednesday Evening 2500'
Wednesday Night 2000'
Thursday Morning 1500'
Thursday Afternoon 3000'
Thursday Evening 2000'
Thursday Night 1500'
Friday Morning 2000'
Friday Afternoon 2500'
West Central Elevation
Wednesday Evening 2500'
Wednesday Night 2000'
Thursday Morning 1500'
Thursday Afternoon 3000'
Thursday Evening 2000'
Thursday Night 1500'
Friday Morning 2500'
Friday Afternoon 3500'
West South Elevation
Wednesday Evening 3500'
Wednesday Night 2500'
Thursday Morning 1500'
Thursday Afternoon 3500'
Thursday Evening 2500'
Thursday Night 1500'
Friday Morning 3000'
Friday Afternoon 4000'
Stevens Pass Elevation
Wednesday Evening 3000'
Wednesday Night 2000'
Thursday Morning 1500'
Thursday Afternoon 3000'
Thursday Evening 2000'
Thursday Night 1500'
Friday Morning 2500'
Friday Afternoon 3500'
Snoqualmie Pass Elevation
Wednesday Evening 3000'
Wednesday Night 2000'
Thursday Morning 1500'
Thursday Afternoon 3000'
Thursday Evening 2000'
Thursday Night 1500'
Friday Morning 2500'
Friday Afternoon 3500'
East North Elevation
Wednesday Evening 3500'
Wednesday Night 2000'
Thursday Morning 2000'
Thursday Afternoon 3500'
Thursday Evening 2500'
Thursday Night 1500'
Friday Morning 3000'
Friday Afternoon 4000'
East Central Elevation
Wednesday Evening 3500'
Wednesday Night 2500'
Thursday Morning 2000'
Thursday Afternoon 3500'
Thursday Evening 2500'
Thursday Night 1500'
Friday Morning 3000'
Friday Afternoon 4500'
East South Elevation
Wednesday Evening 3500'
Wednesday Night 2500'
Thursday Morning 2500'
Thursday Afternoon 3500'
Thursday Evening 2500'
Thursday Night 1500'
Friday Morning 3000'
Friday Afternoon 4500'
Mt. Hood Elevation
Wednesday Evening 4000'
Wednesday Night 3500'
Thursday Morning 2500'
Thursday Afternoon 3500'
Thursday Evening 2500'
Thursday Night 2500'
Friday Morning 3500'
Friday Afternoon 5000'

5000' Temperatures (°F)

Wednesday Night Thursday
Max / Min Max / Min
Olympics 27 / 19 27 / 18
West North 27 / 20 26 / 20
West Central 27 / 19 26 / 19
West South 28 / 20 28 / 20
Stevens Pass 28 / 19 28 / 19
Snoqualmie Pass 27 / 19 27 / 20
East North 29 / 18 28 / 19
East Central 29 / 21 29 / 18
East South 29 / 22 30 / 19
Mt. Hood 29 / 23 31 / 22
Olympics 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 27 / 19
Thursday 5am - 5pm 27 / 18
West North 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 27 / 20
Thursday 5am - 5pm 26 / 20
West Central 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 27 / 19
Thursday 5am - 5pm 26 / 19
West South 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 28 / 20
Thursday 5am - 5pm 28 / 20
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 28 / 19
Thursday 5am - 5pm 28 / 19
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 27 / 19
Thursday 5am - 5pm 27 / 20
East North 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 29 / 18
Thursday 5am - 5pm 28 / 19
East Central 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 29 / 21
Thursday 5am - 5pm 29 / 18
East South 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 29 / 22
Thursday 5am - 5pm 30 / 19
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 29 / 23
Thursday 5am - 5pm 31 / 22

Ridgeline Winds (mph)

Wednesday Evening Wednesday Night Thursday Morning Thursday Afternoon
Olympics WSW 20-30 WNW 15-25 WNW 10-20 W 5-15
West North SW 25-35 W 15-25 W 5-15 SW 5-15
West Central WSW 25-35 W 20-30 W 15-25 W 5-15
West South WSW 30-40 W 30-40 W 20-30 WNW 10-20
Stevens Pass WSW 20-30 W 15-25 W 20-30 NW 10-20
Snoqualmie Pass WSW 25-35 W 30-40 WNW 20-30 NW 10-20
East North WSW 20-30 W 15-25 W 15-25 NW 5-15
East Central W 30-40 W 30-40 W 25-35 NW 10-20
East South W 20-30 W 20-30 W 25-35 NW 5-15
Mt. Hood WSW 30-40 W 35-50 WNW 30-40 WNW 15-25
Olympics Ridgeline Winds (mph)
Wednesday Evening WSW 20-30
Wednesday Night WNW 15-25
Thursday Morning WNW 10-20
Thursday Afternoon W 5-15
West North Ridgeline Winds (mph)
Wednesday Evening SW 25-35
Wednesday Night W 15-25
Thursday Morning W 5-15
Thursday Afternoon SW 5-15
West Central Ridgeline Winds (mph)
Wednesday Evening WSW 25-35
Wednesday Night W 20-30
Thursday Morning W 15-25
Thursday Afternoon W 5-15
West South Ridgeline Winds (mph)
Wednesday Evening WSW 30-40
Wednesday Night W 30-40
Thursday Morning W 20-30
Thursday Afternoon WNW 10-20
Stevens Pass Ridgeline Winds (mph)
Wednesday Evening WSW 20-30
Wednesday Night W 15-25
Thursday Morning W 20-30
Thursday Afternoon NW 10-20
Snoqualmie Pass Ridgeline Winds (mph)
Wednesday Evening WSW 25-35
Wednesday Night W 30-40
Thursday Morning WNW 20-30
Thursday Afternoon NW 10-20
East North Ridgeline Winds (mph)
Wednesday Evening WSW 20-30
Wednesday Night W 15-25
Thursday Morning W 15-25
Thursday Afternoon NW 5-15
East Central Ridgeline Winds (mph)
Wednesday Evening W 30-40
Wednesday Night W 30-40
Thursday Morning W 25-35
Thursday Afternoon NW 10-20
East South Ridgeline Winds (mph)
Wednesday Evening W 20-30
Wednesday Night W 20-30
Thursday Morning W 25-35
Thursday Afternoon NW 5-15
Mt. Hood Ridgeline Winds (mph)
Wednesday Evening WSW 30-40
Wednesday Night W 35-50
Thursday Morning WNW 30-40
Thursday Afternoon WNW 15-25

Extended Weather Synopsis

The front will move through Friday night with another round of cool post-frontal snow showers and blustery winds on Saturday. Ridging will build offshore Saturday night, helping to dry us out, but we'll still be on the cool side Sunday as we sit on the backside of the upper level trough. 

Extended Snow Level (ft)

Friday Night Saturday Saturday Night Sunday
West North 2000' 2000' 1000' 4000'
Snoqualmie Pass 2000' 2500' 1000' 4000'
Mt. Hood 2500' 2500' 1000' 5000'
West North Elevation
Friday Night 2000'
Saturday 2000'
Saturday Night 1000'
Sunday 4000'
Snoqualmie Pass Elevation
Friday Night 2000'
Saturday 2500'
Saturday Night 1000'
Sunday 4000'
Mt. Hood Elevation
Friday Night 2500'
Saturday 2500'
Saturday Night 1000'
Sunday 5000'

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

Previous forecast from Apr 7, 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’.

Updated Mountain Weather Zone Name Changes – December 2020