Issued: 2:48 PM PDT Thursday, April 29, 2021
by Robert Hahn

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

Weather Synopsis

A modest frontal system approaches the Pacific Northwest Friday night, spreading light rain and snow into the Olympics, Mt. Baker, and Mountain Loop regions after midnight. Light to occasionally moderate precipitation shifts from NW to SE across Washington State as Friday progresses. Snow levels should start around 9000-10000 ft, but drop to 6000-8000 ft by late Friday. WSW winds with the system should be in the moderate range for exposed mountain gaps and locations east of the Cascade Crest. Mt. Hood could see a period of sustained moderate to strong winds Friday night, before winds ease Friday.

Light post-frontal showers and weak convergence continue Friday night and Saturday. Convergence likely shifts from the Mountain Loop Friday night to the central Cascades Passes on Saturday. A subtle shortwave may enhance post-frontal showers during the mid-day hours on Saturday. Snow levels lower Friday night to around 4000-5000 ft on Saturday.

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
Thursday Night Mostly cloudy in the evening with light rain showers likely in the early morning hours.
Friday Decreasing light rain and high elevation snow showers.
Thursday Night Mostly cloudy in the evening with light rain showers likely in the early morning hours.
Friday Decreasing light rain and high elevation snow showers.
Thursday Night Increasing clouds in the evening with light rain showers likely in the early morning hours.
Friday Light to moderate rain and high elevation snow showers.
Thursday Night Increasing high clouds, lowering and thickening toward morning.
Friday Increasing light rain and high elevation snow showers potentially becoming moderate at Paradise.
Thursday Night Increasing high clouds, lowering and thickening toward morning.
Friday Light rain and high elevation snow showers.
Thursday Night Increasing high clouds, lowering and thickening toward morning.
Friday Light rain and high elevation snow showers.
Thursday Night Increasing high clouds, lowering and thickening toward morning.
Friday Increasing light rain and high elevation snow showers.
Thursday Night Increasing high clouds, lowering and thickening toward morning.
Friday Increasing light rain and high elevation snow showers.
Thursday Night Increasing and thickening clouds.
Friday Mostly cloudy with light rain or high elevation snow showers developing as the day progresses.
Thursday Night Thickening high clouds.
Friday Mostly cloudy with a chance of rain or high elevation snow late in the day.

Precipitation (in)

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

Snow Level (ft)

Thursday Evening Thursday Night Friday Morning Friday Afternoon Friday Evening Friday Night Saturday Morning Saturday Afternoon
Olympics 10500' 9500' 7500' 7000' 6500' 6000' 4000' 4500'
West North 9500' 9000' 7500' 6500' 6000' 5500' 4000' 4500'
West Central 1100' 10000' 8000' 7000' 6500' 5500' 4000' 4500'
West South 12500' 12000' 9500' 8000' 7000' 7000' 4500' 5000'
Stevens Pass 11500' 11500' 8500' 7500' 6500' 6000' 4000' 4500'
Snoqualmie Pass 11500' 11500' 8500' 7500' 6500' 6000' 4000' 4500'
East North 10000' 11000' 8000' 7500' 7000' 6000' 5000' 5000'
East Central 12000' 12000' 10000' 8000' 7000' 6000' 5000' 5000'
East South 13000' 12500' 11500' 9000' 7500' 8500' 6500' 6500'
Mt. Hood 13500' 13000' 12000' 9500' 8500' 8000' 7500' 6500'
Olympics Elevation
Thursday Evening 10500'
Thursday Night 9500'
Friday Morning 7500'
Friday Afternoon 7000'
Friday Evening 6500'
Friday Night 6000'
Saturday Morning 4000'
Saturday Afternoon 4500'
West North Elevation
Thursday Evening 9500'
Thursday Night 9000'
Friday Morning 7500'
Friday Afternoon 6500'
Friday Evening 6000'
Friday Night 5500'
Saturday Morning 4000'
Saturday Afternoon 4500'
West Central Elevation
Thursday Evening 1100'
Thursday Night 10000'
Friday Morning 8000'
Friday Afternoon 7000'
Friday Evening 6500'
Friday Night 5500'
Saturday Morning 4000'
Saturday Afternoon 4500'
West South Elevation
Thursday Evening 12500'
Thursday Night 12000'
Friday Morning 9500'
Friday Afternoon 8000'
Friday Evening 7000'
Friday Night 7000'
Saturday Morning 4500'
Saturday Afternoon 5000'
Stevens Pass Elevation
Thursday Evening 11500'
Thursday Night 11500'
Friday Morning 8500'
Friday Afternoon 7500'
Friday Evening 6500'
Friday Night 6000'
Saturday Morning 4000'
Saturday Afternoon 4500'
Snoqualmie Pass Elevation
Thursday Evening 11500'
Thursday Night 11500'
Friday Morning 8500'
Friday Afternoon 7500'
Friday Evening 6500'
Friday Night 6000'
Saturday Morning 4000'
Saturday Afternoon 4500'
East North Elevation
Thursday Evening 10000'
Thursday Night 11000'
Friday Morning 8000'
Friday Afternoon 7500'
Friday Evening 7000'
Friday Night 6000'
Saturday Morning 5000'
Saturday Afternoon 5000'
East Central Elevation
Thursday Evening 12000'
Thursday Night 12000'
Friday Morning 10000'
Friday Afternoon 8000'
Friday Evening 7000'
Friday Night 6000'
Saturday Morning 5000'
Saturday Afternoon 5000'
East South Elevation
Thursday Evening 13000'
Thursday Night 12500'
Friday Morning 11500'
Friday Afternoon 9000'
Friday Evening 7500'
Friday Night 8500'
Saturday Morning 6500'
Saturday Afternoon 6500'
Mt. Hood Elevation
Thursday Evening 13500'
Thursday Night 13000'
Friday Morning 12000'
Friday Afternoon 9500'
Friday Evening 8500'
Friday Night 8000'
Saturday Morning 7500'
Saturday Afternoon 6500'

5000' Temperatures (°F)

Thursday Night Friday
Max / Min Max / Min
Olympics 43 / 38 40 / 37
West North 44 / 36 38 / 36
West Central 44 / 35 37 / 36
West South 50 / 36 40 / 35
Stevens Pass 49 / 35 40 / 35
Snoqualmie Pass 45 / 34 38 / 34
East North 48 / 37 41 / 38
East Central 48 / 37 41 / 38
East South 52 / 37 46 / 37
Mt. Hood 52 / 40 50 / 39
Olympics 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 43 / 38
Friday 5am - 5pm 40 / 37
West North 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 44 / 36
Friday 5am - 5pm 38 / 36
West Central 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 44 / 35
Friday 5am - 5pm 37 / 36
West South 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 50 / 36
Friday 5am - 5pm 40 / 35
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 49 / 35
Friday 5am - 5pm 40 / 35
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 45 / 34
Friday 5am - 5pm 38 / 34
East North 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 48 / 37
Friday 5am - 5pm 41 / 38
East Central 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 48 / 37
Friday 5am - 5pm 41 / 38
East South 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 52 / 37
Friday 5am - 5pm 46 / 37
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Thursday 5pm - 5am 52 / 40
Friday 5am - 5pm 50 / 39

Ridgeline Winds (mph)

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

Extended Weather Synopsis

Light post-frontal rain/snow showers and convergence decrease and end Saturday night. Moderate westerly ridgeline winds through the mountain gaps and along the east slopes of the Cascades may persist into early Sunday before decreasing as upper-level flow turns NWerly. Sunday and Sunday night should be mostly dry. A weak frontal system moves in during the day on Monday with another round of light rain/snow showers. Temperatures remain near seasonal norms with a warming trend into Sunday night and Monday.

Extended Snow Level (ft)

Saturday Night Sunday Sunday Night Monday
West North 5000' 4500' 5500' 5000'
Snoqualmie Pass 4500' 4500' 5500' 6000'
Mt. Hood 5000' 4500' 6500' 7000'
West North Elevation
Saturday Night 5000'
Sunday 4500'
Sunday Night 5500'
Monday 5000'
Snoqualmie Pass Elevation
Saturday Night 4500'
Sunday 4500'
Sunday Night 5500'
Monday 6000'
Mt. Hood Elevation
Saturday Night 5000'
Sunday 4500'
Sunday Night 6500'
Monday 7000'

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

Previous forecast from Apr 28, 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