Issued: 2:34 PM PDT Wednesday, April 28, 2021
by Dennis D'Amico

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

Weather Synopsis

A ridge of high pressure along the coast continues to direct the storm track into central British Columba this afternoon while allowing a significant amount of high clouds to drape over the region. This pattern of dry weather but thicker high clouds near the Canadian border and more of a patchwork for areas further south will continue into Thursday morning as the ridge axis shifts inland. Temperatures will be quite mild overnight as warmer air moves into the region.

As the ridge axis amplifies on Thursday, cloud cover will shift north and most areas should transition to mostly sunny skies. Temperatures and freezing levels will soar Thursday afternoon for what will be the warmest day this week. 

A weak frontal system will begin to break down the ridge late Thursday night into Friday. Light rain should reach the Olympics and northwest Cascades by daybreak and light to locally moderate precipitation will slowly move inland during the day. Precipitation won't likely make it as far south as Mt Hood area during the daylight hours. Cloud cover and ridgeline winds will increase as snow levels slowly fall during the day. 

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 Cloudy in the evening then mostly cloudy after midnight.
Thursday Mostly cloudy in the morning then partly sunny in the afternoon with periods of high clouds.
Wednesday Night Cloudy in the evening then mostly cloudy after midnight.
Thursday Mostly cloudy in the morning then partly sunny in the afternoon with periods of high clouds.
Wednesday Night Cloudy in the evening then mostly cloudy after midnight.
Thursday Mostly cloudy in the morning with periods of high clouds then partly to mostly sunny in the afternoon.
Wednesday Night Partly to mostly cloudy with periods of high clouds.
Thursday Mostly cloudy in the morning with periods of high clouds then mostly sunny in the afternoon.
Wednesday Night Mostly cloudy with periods of high clouds.
Thursday Mostly cloudy in the morning with periods of high clouds then mostly sunny in the afternoon.
Wednesday Night Partly to mostly cloudy with periods of high clouds.
Thursday Mostly cloudy in the morning with periods of high clouds then mostly sunny in the afternoon.
Wednesday Night Mostly cloudy with periods of high clouds.
Thursday Mostly cloudy in the morning with periods of high clouds then mostly sunny in the afternoon.
Wednesday Night Partly to mostly cloudy with periods of high clouds.
Thursday Mostly cloudy in the morning with periods of high clouds then mostly sunny in the afternoon.
Wednesday Night Partly to mostly cloudy with periods of high clouds.
Thursday Mostly cloudy in the morning with periods of high clouds then mostly sunny in the afternoon.
Wednesday Night Partly cloudy with periods of high clouds.
Thursday Partly cloudy in the morning with periods of high clouds then sunny in the afternoon.

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 0 LT 0.10 LT 0.25
Mt Baker Ski Area 0 0 LT 0.10 0.25 - 0.50
Mt. Loop - Barlow Pass 0 0 0 0.25 - 0.50
Stevens Pass 0 0 0 LT 0.25
Snoqualmie Pass 0 0 0 LT 0.25
Crystal Mt 0 0 0 LT 0.10
Paradise 0 0 0 LT 0.25
White Pass 0 0 0 LT 0.10
Washington Pass 0 0 0 LT 0.10
Mission Ridge 0 0 0 0
Salmon la Sac - Gallagher Head 0 0 0 LT 0.10
Tieton River - Darland Mt. 0 0 0 0
Mt Hood Meadows 0 0 0 0
Timberline 0 0 0 0
Hurricane Ridge Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night LT 0.10
Friday LT 0.25
Mt Baker Ski Area Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night LT 0.10
Friday 0.25 - 0.50
Mt. Loop - Barlow Pass Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday 0.25 - 0.50
Stevens Pass Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.25
Snoqualmie Pass Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.25
Crystal Mt Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.10
Paradise Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.25
White Pass Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.10
Washington Pass Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.10
Mission Ridge Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday LT 0.10
Tieton River - Darland Mt. Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday 0
Mt Hood Meadows Precipitation (in)
Wednesday Night 0
Thursday 0
Thursday Night 0
Friday 0
Timberline Precipitation (in)
Wednesday Night 0
Thursday 0
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 9500' 10500' 11000' 11500' 9000' 7000' 7000' 6500'
West North 7500' 9000' 9500' 10000' 9000' 7000' 7000' 6500'
West Central 9500' 11000' 11500' 12000' 10000' 8500' 7500' 7000'
West South 11000' 11500' 12000' 12500' 11000' 10000' 8500' 7500'
Stevens Pass 10000' 11000' 11500' 12000' 10000' 9000' 8500' 7000'
Snoqualmie Pass 10000' 11000' 11500' 12000' 10000' 9000' 8500' 7000'
East North 9000' 9500' 10000' 10500' 10500' 10000' 8500' 7500'
East Central 10500' 11000' 11500' 12000' 11500' 11000' 9500' 8000'
East South 11000' 11000' 12000' 12500' 11500' 11000' 9500' 8500'
Mt. Hood 12000' 12000' 12500' 13500' 13000' 12500' 11000' 10000'
Olympics Elevation
Wednesday Evening 9500'
Wednesday Night 10500'
Thursday Morning 11000'
Thursday Afternoon 11500'
Thursday Evening 9000'
Thursday Night 7000'
Friday Morning 7000'
Friday Afternoon 6500'
West North Elevation
Wednesday Evening 7500'
Wednesday Night 9000'
Thursday Morning 9500'
Thursday Afternoon 10000'
Thursday Evening 9000'
Thursday Night 7000'
Friday Morning 7000'
Friday Afternoon 6500'
West Central Elevation
Wednesday Evening 9500'
Wednesday Night 11000'
Thursday Morning 11500'
Thursday Afternoon 12000'
Thursday Evening 10000'
Thursday Night 8500'
Friday Morning 7500'
Friday Afternoon 7000'
West South Elevation
Wednesday Evening 11000'
Wednesday Night 11500'
Thursday Morning 12000'
Thursday Afternoon 12500'
Thursday Evening 11000'
Thursday Night 10000'
Friday Morning 8500'
Friday Afternoon 7500'
Stevens Pass Elevation
Wednesday Evening 10000'
Wednesday Night 11000'
Thursday Morning 11500'
Thursday Afternoon 12000'
Thursday Evening 10000'
Thursday Night 9000'
Friday Morning 8500'
Friday Afternoon 7000'
Snoqualmie Pass Elevation
Wednesday Evening 10000'
Wednesday Night 11000'
Thursday Morning 11500'
Thursday Afternoon 12000'
Thursday Evening 10000'
Thursday Night 9000'
Friday Morning 8500'
Friday Afternoon 7000'
East North Elevation
Wednesday Evening 9000'
Wednesday Night 9500'
Thursday Morning 10000'
Thursday Afternoon 10500'
Thursday Evening 10500'
Thursday Night 10000'
Friday Morning 8500'
Friday Afternoon 7500'
East Central Elevation
Wednesday Evening 10500'
Wednesday Night 11000'
Thursday Morning 11500'
Thursday Afternoon 12000'
Thursday Evening 11500'
Thursday Night 11000'
Friday Morning 9500'
Friday Afternoon 8000'
East South Elevation
Wednesday Evening 11000'
Wednesday Night 11000'
Thursday Morning 12000'
Thursday Afternoon 12500'
Thursday Evening 11500'
Thursday Night 11000'
Friday Morning 9500'
Friday Afternoon 8500'
Mt. Hood Elevation
Wednesday Evening 12000'
Wednesday Night 12000'
Thursday Morning 12500'
Thursday Afternoon 13500'
Thursday Evening 13000'
Thursday Night 12500'
Friday Morning 11000'
Friday Afternoon 10000'

5000' Temperatures (°F)

Wednesday Night Thursday
Max / Min Max / Min
Olympics 43 / 40 53 / 43
West North 40 / 39 53 / 41
West Central 42 / 42 56 / 43
West South 49 / 42 59 / 43
Stevens Pass 46 / 40 58 / 43
Snoqualmie Pass 44 / 42 57 / 44
East North 43 / 40 57 / 43
East Central 48 / 43 58 / 44
East South 51 / 44 60 / 45
Mt. Hood 53 / 45 62 / 46
Olympics 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 43 / 40
Thursday 5am - 5pm 53 / 43
West North 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 40 / 39
Thursday 5am - 5pm 53 / 41
West Central 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 42 / 42
Thursday 5am - 5pm 56 / 43
West South 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 49 / 42
Thursday 5am - 5pm 59 / 43
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 46 / 40
Thursday 5am - 5pm 58 / 43
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 44 / 42
Thursday 5am - 5pm 57 / 44
East North 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 43 / 40
Thursday 5am - 5pm 57 / 43
East Central 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 48 / 43
Thursday 5am - 5pm 58 / 44
East South 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 51 / 44
Thursday 5am - 5pm 60 / 45
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Wednesday 5pm - 5am 53 / 45
Thursday 5am - 5pm 62 / 46

Ridgeline Winds (mph)

Wednesday Evening Wednesday Night Thursday Morning Thursday Afternoon
Olympics SW 5-15 SW 5-15 SW 5-15 SW 10-20
West North SSW 10-20 SW 5-15 SSW 10-20 SSW 15-25
West Central SW 0-10 SW 0-10 SSW 0-10 SW 10-20
West South WSW 5-15 SW 5-15 SW 5-15 SW 5-15
Stevens Pass W 5-15 WSW 5-15 WSW 5-15 SW 5-15
Snoqualmie Pass W 10-20 WSW 5-15 WSW 5-15 SW 5-15
East North W 10-20 WSW 5-15 SW 0-10 SW 5-15
East Central W 10-20 W 5-15 SW 5-15 SW 5-15
East South W 5-15 W 5-15 SW 5-15 SW 5-15
Mt. Hood SW 5-15 WSW 5-15 SW 5-15 SW 10-20
Olympics Ridgeline Winds (mph)
Wednesday Evening SW 5-15
Wednesday Night SW 5-15
Thursday Morning SW 5-15
Thursday Afternoon SW 10-20
West North Ridgeline Winds (mph)
Wednesday Evening SSW 10-20
Wednesday Night SW 5-15
Thursday Morning SSW 10-20
Thursday Afternoon SSW 15-25
West Central Ridgeline Winds (mph)
Wednesday Evening SW 0-10
Wednesday Night SW 0-10
Thursday Morning SSW 0-10
Thursday Afternoon SW 10-20
West South Ridgeline Winds (mph)
Wednesday Evening WSW 5-15
Wednesday Night SW 5-15
Thursday Morning SW 5-15
Thursday Afternoon SW 5-15
Stevens Pass Ridgeline Winds (mph)
Wednesday Evening W 5-15
Wednesday Night WSW 5-15
Thursday Morning WSW 5-15
Thursday Afternoon SW 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Wednesday Evening W 10-20
Wednesday Night WSW 5-15
Thursday Morning WSW 5-15
Thursday Afternoon SW 5-15
East North Ridgeline Winds (mph)
Wednesday Evening W 10-20
Wednesday Night WSW 5-15
Thursday Morning SW 0-10
Thursday Afternoon SW 5-15
East Central Ridgeline Winds (mph)
Wednesday Evening W 10-20
Wednesday Night W 5-15
Thursday Morning SW 5-15
Thursday Afternoon SW 5-15
East South Ridgeline Winds (mph)
Wednesday Evening W 5-15
Wednesday Night W 5-15
Thursday Morning SW 5-15
Thursday Afternoon SW 5-15
Mt. Hood Ridgeline Winds (mph)
Wednesday Evening SW 5-15
Wednesday Night WSW 5-15
Thursday Morning SW 5-15
Thursday Afternoon SW 10-20

Extended Weather Synopsis

The front will pass inland Friday evening and post-frontal showers and a convergence zone will be the main features Friday night and Saturday, with a few inches of snow along the west slopes of the Cascades above 4500-5000'.  Less precipitation is expected along the east slopes of the Cascades and Mt Hood.  On Sunday, a shortwave ridge will help trap moisture along the west slopes of the Cascades with an isolated shower or two. More sunshine and warmer temperatures are expected for the Mt Hood area and along the east slopes of Cascades. 

Extended Snow Level (ft)

Friday Night Saturday Saturday Night Sunday
West North 5000' 4500' 3500' 5000'
Snoqualmie Pass 5000' 4500' 3500' 5000'
Mt. Hood 6500' 5500' 4000' 6000'
West North Elevation
Friday Night 5000'
Saturday 4500'
Saturday Night 3500'
Sunday 5000'
Snoqualmie Pass Elevation
Friday Night 5000'
Saturday 4500'
Saturday Night 3500'
Sunday 5000'
Mt. Hood Elevation
Friday Night 6500'
Saturday 5500'
Saturday Night 4000'
Sunday 6000'

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

Previous forecast from Apr 27, 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