Issued: 2:25 PM PDT Tuesday, April 27, 2021
by Dennis D'Amico

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

Weather Synopsis

The storm track is riding up and over a ridge of high pressure centered offshore, directing ample precipitation into central British Columbia but largely missing the Pacific Northwest in terms of raindrops or snowflakes. However, plenty of cloud cover, a mix of lower-level stratocu and high-level cirrus can be found over the region, with decreasing sky cover the further you travel south toward the Washington/Oregon border. 

This pattern will continue overnight and into tomorrow with the southern dregs of frontal systems covering the Olympics and north Cascades and with waves of filtered sunshine giving way to clearer skies the further one travels south from the Canadian border to Mt Hood. As the ridge axis slides closer to our coast tomorrow, warmer air will begin to flood the region, again most pronounced for southern areas. Some very light precipitation may glance the northwest Cascades Wednesday afternoon or night. 

The ridge will shift inland Wednesday night and we'll see freezing levels climb to 10,000 ft or higher over much of the region. As the ridge amplifies over the inland NW, this should help slow and stand up the next frontal system offshore, leaving us with the warmest temps/highest freezing levels of the week and fewer high clouds to contend with than Tue/Wed. 5000' temps should rise into the 50s and lower 60s on Thursday. 

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 Night Cloudy.
Wednesday Cloudy.
Tuesday Night Cloudy.
Wednesday Cloudy.
Tuesday Night Cloudy in the evening, partial clearing after midnight.
Wednesday Mostly cloudy with periods of filtered sunshine.
Tuesday Night High overcast becoming partly cloudy after midnight.
Wednesday Partly sunny with periods of filtered sunshine.
Tuesday Night Cloudy in the evening, partial clearing after midnight.
Wednesday Mostly cloudy with periods of filtered sunshine.
Tuesday Night Cloudy in the evening, partial clearing after midnight.
Wednesday Mostly cloudy with periods of filtered sunshine.
Tuesday Night Cloudy.
Wednesday Mostly cloudy with periods of filtered sunshine.
Tuesday Night High overcast becoming partly cloudy after midnight.
Wednesday Partly sunny with periods of filtered sunshine.
Tuesday Night High overcast becoming partly cloudy after midnight.
Wednesday Partly sunny with periods of filtered sunshine.
Tuesday Night High overcast becoming partly cloudy after midnight.
Wednesday Partly to mostly sunny with periods of filtered sunshine.

Precipitation (in)

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

Snow Level (ft)

Tuesday Evening Tuesday Night Wednesday Morning Wednesday Afternoon Wednesday Evening Wednesday Night Thursday Morning Thursday Afternoon
Olympics 6500' 6500' 8000' 8500' 9000' 11000' 11000' 11500'
West North 6000' 5000' 6000' 7500' 8500' 9000' 10000' 11000'
West Central 6000' 5000' 6500' 9000' 9500' 10000' 11000' 11500'
West South 6000' 7000' 9000' 10000' 10500' 11500' 12000' 13000'
Stevens Pass 6000' 4500' 6500' 9000' 9500' 10000' 11000' 12000'
Snoqualmie Pass 6000' 4500' 7000' 9500' 10000' 11000' 11500' 12000'
East North 5500' 5000' 6000' 9000' 9500' 9500' 10500' 11000'
East Central 6500' 6500' 8000' 10000' 10500' 11000' 11500' 12000'
East South 7000' 7000' 9000' 11000' 11500' 12000' 12500' 13000'
Mt. Hood 9000' 10000' 11000' 11500' 11500' 12000' 13000' 14000'
Olympics Elevation
Tuesday Evening 6500'
Tuesday Night 6500'
Wednesday Morning 8000'
Wednesday Afternoon 8500'
Wednesday Evening 9000'
Wednesday Night 11000'
Thursday Morning 11000'
Thursday Afternoon 11500'
West North Elevation
Tuesday Evening 6000'
Tuesday Night 5000'
Wednesday Morning 6000'
Wednesday Afternoon 7500'
Wednesday Evening 8500'
Wednesday Night 9000'
Thursday Morning 10000'
Thursday Afternoon 11000'
West Central Elevation
Tuesday Evening 6000'
Tuesday Night 5000'
Wednesday Morning 6500'
Wednesday Afternoon 9000'
Wednesday Evening 9500'
Wednesday Night 10000'
Thursday Morning 11000'
Thursday Afternoon 11500'
West South Elevation
Tuesday Evening 6000'
Tuesday Night 7000'
Wednesday Morning 9000'
Wednesday Afternoon 10000'
Wednesday Evening 10500'
Wednesday Night 11500'
Thursday Morning 12000'
Thursday Afternoon 13000'
Stevens Pass Elevation
Tuesday Evening 6000'
Tuesday Night 4500'
Wednesday Morning 6500'
Wednesday Afternoon 9000'
Wednesday Evening 9500'
Wednesday Night 10000'
Thursday Morning 11000'
Thursday Afternoon 12000'
Snoqualmie Pass Elevation
Tuesday Evening 6000'
Tuesday Night 4500'
Wednesday Morning 7000'
Wednesday Afternoon 9500'
Wednesday Evening 10000'
Wednesday Night 11000'
Thursday Morning 11500'
Thursday Afternoon 12000'
East North Elevation
Tuesday Evening 5500'
Tuesday Night 5000'
Wednesday Morning 6000'
Wednesday Afternoon 9000'
Wednesday Evening 9500'
Wednesday Night 9500'
Thursday Morning 10500'
Thursday Afternoon 11000'
East Central Elevation
Tuesday Evening 6500'
Tuesday Night 6500'
Wednesday Morning 8000'
Wednesday Afternoon 10000'
Wednesday Evening 10500'
Wednesday Night 11000'
Thursday Morning 11500'
Thursday Afternoon 12000'
East South Elevation
Tuesday Evening 7000'
Tuesday Night 7000'
Wednesday Morning 9000'
Wednesday Afternoon 11000'
Wednesday Evening 11500'
Wednesday Night 12000'
Thursday Morning 12500'
Thursday Afternoon 13000'
Mt. Hood Elevation
Tuesday Evening 9000'
Tuesday Night 10000'
Wednesday Morning 11000'
Wednesday Afternoon 11500'
Wednesday Evening 11500'
Wednesday Night 12000'
Thursday Morning 13000'
Thursday Afternoon 14000'

5000' Temperatures (°F)

Tuesday Night Wednesday
Max / Min Max / Min
Olympics 36 / 33 46 / 36
West North 35 / 32 44 / 34
West Central 36 / 32 46 / 34
West South 40 / 32 52 / 35
Stevens Pass 38 / 33 49 / 34
Snoqualmie Pass 36 / 32 47 / 34
East North 38 / 32 46 / 33
East Central 38 / 32 51 / 36
East South 41 / 35 54 / 37
Mt. Hood 43 / 35 56 / 37
Olympics 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 36 / 33
Wednesday 5am - 5pm 46 / 36
West North 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 35 / 32
Wednesday 5am - 5pm 44 / 34
West Central 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 36 / 32
Wednesday 5am - 5pm 46 / 34
West South 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 40 / 32
Wednesday 5am - 5pm 52 / 35
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 38 / 33
Wednesday 5am - 5pm 49 / 34
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 36 / 32
Wednesday 5am - 5pm 47 / 34
East North 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 38 / 32
Wednesday 5am - 5pm 46 / 33
East Central 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 38 / 32
Wednesday 5am - 5pm 51 / 36
East South 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 41 / 35
Wednesday 5am - 5pm 54 / 37
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Tuesday 5pm - 5am 43 / 35
Wednesday 5am - 5pm 56 / 37

Ridgeline Winds (mph)

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

Extended Weather Synopsis

The aforementioned Pacific frontal system crashes into the ridge on Friday. This system doesn't look like a big precipitation producer but will collapse the ridge and open the door to more unsettled weather. A trough should move overhead Friday night and Saturday with light to locally moderate showers for the west slopes of the Cascades and lighter and scattered showers elsewhere. Snow levels will steadily decrease over this period as well. 

Extended Snow Level (ft)

Thursday Night Friday Friday Night Saturday
West North 7500' 7000' 5000' 4500'
Snoqualmie Pass 9000' 7500' 5500' 4500'
Mt. Hood 12000' 9000' 6500' 5500'
West North Elevation
Thursday Night 7500'
Friday 7000'
Friday Night 5000'
Saturday 4500'
Snoqualmie Pass Elevation
Thursday Night 9000'
Friday 7500'
Friday Night 5500'
Saturday 4500'
Mt. Hood Elevation
Thursday Night 12000'
Friday 9000'
Friday Night 6500'
Saturday 5500'

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

Previous forecast from Apr 26, 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