Issued: 2:52 PM PDT Thursday, April 27, 2023
by Robert Hahn

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

Weather Synopsis

A large-scale and expanding ridge of high pressure dominates the western United States on Thursday, bringing sunny, dry, and warmer than average temperatures to the region. Only the Washington Pass base station dropped below freezing (briefly) on Wednesday night. Large-scale sinking air associated with the high pressure will keep freezing levels in the 11,500-13,500 ft range across the region along with mostly sunny skies through Saturday. A thermal trough moving northward along the coast will induce mostly light low low-level offshore flow through Friday, which eases Friday night. This offshore flow will increase temperatures to the west of the Cascade Crest (with downslope wind), making Friday the warmest day of the stretch for these locations.

The ridge axis shifts east of the region Friday night, but remains dominant on Saturday. Light SSW upper-level winds develop ahead of a closed low well offshore. Low-level westerly flow will slightly lower high temperatures west of the Cascade Crest, while east of the Crest, temperatures should peak with this warm period on Saturday afternoon.

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 Mild and mostly clear with thin high clouds mainly after midnight.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mild and mostly clear with thin high clouds mainly after midnight.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mild and mostly clear with thin high clouds mainly after midnight.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mostly clear and mild.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mostly clear and mild. Light ridgeline and E wind at the Pass.
Friday Sunny and unseasonably warm. Very thin high clouds at times. Light ridgeline and E wind at the Pass.
Thursday Night Mostly clear and mild. Light ridgeline and light to occasionally moderate E wind at the Pass.
Friday Sunny and unseasonably warm. Very thin high clouds at times. Light ridgeline and light to occasionally moderate E wind at the Pass.
Thursday Night Mild and mostly clear with thin high clouds mainly after midnight.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mostly clear and mild.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mostly clear and mild.
Friday Sunny and unseasonably warm. Very thin high clouds at times.
Thursday Night Mostly clear and mild.
Friday Sunny and unseasonably warm. Very thin high clouds at times.

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 0 0 0 0
Mt Baker Ski Area 0 0 0 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)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Mt Baker Ski Area Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Mt. Loop - Barlow Pass Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Stevens Pass Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Snoqualmie Pass Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Crystal Mt Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Paradise Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
White Pass Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Washington Pass Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
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 0
Friday Night 0
Saturday 0
Tieton River - Darland Mt. Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Mt Hood Meadows Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0
Timberline Precipitation (in)
Thursday Night 0
Friday 0
Friday Night 0
Saturday 0

Snow Level (ft)

Thursday Evening Thursday Night* Friday Morning* Friday Afternoon* Friday Evening* Friday Night* Saturday Morning Saturday Afternoon
Olympics 12500' 13500' 13000' 13000' 13000' 12500' 12500' 12000'
West North 11500' 12500' 12500' 13000' 12500' 12000' 11500' 11500'
West Central 12000' 12500' 13000' 13000' 13000' 12500' 12000' 12000'
West South 12500' 13000' 13000' 13000' 13000' 12500' 12500' 12000'
Stevens Pass 12000' 12500' 13000' 13000' 13000' 12500' 12000' 12000'
Snoqualmie Pass 12000' 13000' 13000' 13000' 13000' 12500' 12500' 12000'
East North 11500' 12000' 12000' 13000' 13000' 12500' 11500' 11500'
East Central 12000' 13000' 13000' 13000' 13000' 12500' 12000' 12000'
East South 12500' 13000' 13000' 13000' 13000' 12500' 12500' 12500'
Mt. Hood 13000' 13500' 13500' 13500' 13000' 12500' 12500' 12000'
Olympics Elevation
Thursday Evening 12500'
Thursday Night* 13500'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12500'
Saturday Afternoon 12000'
West North Elevation
Thursday Evening 11500'
Thursday Night* 12500'
Friday Morning* 12500'
Friday Afternoon* 13000'
Friday Evening* 12500'
Friday Night* 12000'
Saturday Morning 11500'
Saturday Afternoon 11500'
West Central Elevation
Thursday Evening 12000'
Thursday Night* 12500'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12000'
Saturday Afternoon 12000'
West South Elevation
Thursday Evening 12500'
Thursday Night* 13000'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12500'
Saturday Afternoon 12000'
Stevens Pass Elevation
Thursday Evening 12000'
Thursday Night* 12500'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12000'
Saturday Afternoon 12000'
Snoqualmie Pass Elevation
Thursday Evening 12000'
Thursday Night* 13000'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12500'
Saturday Afternoon 12000'
East North Elevation
Thursday Evening 11500'
Thursday Night* 12000'
Friday Morning* 12000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 11500'
Saturday Afternoon 11500'
East Central Elevation
Thursday Evening 12000'
Thursday Night* 13000'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12000'
Saturday Afternoon 12000'
East South Elevation
Thursday Evening 12500'
Thursday Night* 13000'
Friday Morning* 13000'
Friday Afternoon* 13000'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12500'
Saturday Afternoon 12500'
Mt. Hood Elevation
Thursday Evening 13000'
Thursday Night* 13500'
Friday Morning* 13500'
Friday Afternoon* 13500'
Friday Evening* 13000'
Friday Night* 12500'
Saturday Morning 12500'
Saturday Afternoon 12000'

5000' Temperatures (°F)

Thursday Night Friday
Max / Min Max / Min
Olympics 50 / 46 62 / 46
West North 49 / 43 58 / 47
West Central 50 / 44 55 / 45
West South 56 / 43 65 / 44
Stevens Pass 55 / 43 59 / 43
Snoqualmie Pass 51 / 42 54 / 42
East North 52 / 39 57 / 38
East Central 52 / 43 57 / 43
East South 53 / 42 60 / 42
Mt. Hood 54 / 45 65 / 46
Olympics 5000' Temperature Forecast
(Max / Min)
Thursday Night 50 / 46
Friday 62 / 46
West North 5000' Temperature Forecast
(Max / Min)
Thursday Night 49 / 43
Friday 58 / 47
West Central 5000' Temperature Forecast
(Max / Min)
Thursday Night 50 / 44
Friday 55 / 45
West South 5000' Temperature Forecast
(Max / Min)
Thursday Night 56 / 43
Friday 65 / 44
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Thursday Night 55 / 43
Friday 59 / 43
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Thursday Night 51 / 42
Friday 54 / 42
East North 5000' Temperature Forecast
(Max / Min)
Thursday Night 52 / 39
Friday 57 / 38
East Central 5000' Temperature Forecast
(Max / Min)
Thursday Night 52 / 43
Friday 57 / 43
East South 5000' Temperature Forecast
(Max / Min)
Thursday Night 53 / 42
Friday 60 / 42
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Thursday Night 54 / 45
Friday 65 / 46

Ridgeline Winds (mph)

Thursday Evening Thursday Night Friday Morning Friday Afternoon
Olympics S 0-10 S 0-10 S 0-10 SW 0-10
West North S 5-15 SSW 0-10 S 0-10 S 0-10
West Central SSE 0-10 SE 5-15 SE 5-15 ESE 5-15
West South ESE 0-10 SE 0-10 SSE 5-15 S 0-10
Stevens Pass SSE 0-10 SSE 5-15 SE 5-15 SE 5-15
Snoqualmie Pass ESE 0-10 ESE 5-15 ESE 10-20 SE 10-20
East North SW 0-10 S 5-15 S 5-15 SE 0-10
East Central SSW 0-10 S 5-15 S 10-20 S 5-15
East South SE 0-10 SE 5-15 SE 5-15 SSE 5-15
Mt. Hood S 0-10 S 5-15 S 15-25 SW 0-10
Olympics Ridgeline Winds (mph)
Thursday Evening S 0-10
Thursday Night S 0-10
Friday Morning S 0-10
Friday Afternoon SW 0-10
West North Ridgeline Winds (mph)
Thursday Evening S 5-15
Thursday Night SSW 0-10
Friday Morning S 0-10
Friday Afternoon S 0-10
West Central Ridgeline Winds (mph)
Thursday Evening SSE 0-10
Thursday Night SE 5-15
Friday Morning SE 5-15
Friday Afternoon ESE 5-15
West South Ridgeline Winds (mph)
Thursday Evening ESE 0-10
Thursday Night SE 0-10
Friday Morning SSE 5-15
Friday Afternoon S 0-10
Stevens Pass Ridgeline Winds (mph)
Thursday Evening SSE 0-10
Thursday Night SSE 5-15
Friday Morning SE 5-15
Friday Afternoon SE 5-15
Snoqualmie Pass Ridgeline Winds (mph)
Thursday Evening ESE 0-10
Thursday Night ESE 5-15
Friday Morning ESE 10-20
Friday Afternoon SE 10-20
East North Ridgeline Winds (mph)
Thursday Evening SW 0-10
Thursday Night S 5-15
Friday Morning S 5-15
Friday Afternoon SE 0-10
East Central Ridgeline Winds (mph)
Thursday Evening SSW 0-10
Thursday Night S 5-15
Friday Morning S 10-20
Friday Afternoon S 5-15
East South Ridgeline Winds (mph)
Thursday Evening SE 0-10
Thursday Night SE 5-15
Friday Morning SE 5-15
Friday Afternoon SSE 5-15
Mt. Hood Ridgeline Winds (mph)
Thursday Evening S 0-10
Thursday Night S 5-15
Friday Morning S 15-25
Friday Afternoon SW 0-10

Extended Weather Synopsis

Temperatures cool slightly as the offshore closed low approaches the region Saturday night and Sunday. Some instability may develop with a chance of showers and mostly modest Thunderstorms increasing during the day on Sunday. Thunderstorms will ride along the Cascade Crest and push to the east slopes with the highest chances of more dangerous storms to the north and east of Mazama. Isolated shower activity continues Sunday night and Monday as the low stalls in the near-shore waters and begins to drift southward. Temperatures will be significantly cooler in regions closer to the coast. Overnight refreezes should be poor except at higher elevations.

Extended Snow Level (ft)

Saturday Night Sunday Sunday Night Monday
West North 11000' 8000' 7500' 8500'
Snoqualmie Pass 11500' 9000' 8000' 6500'
Mt. Hood 11500' 10500' 7500' 5500'
West North Elevation
Saturday Night 11000'
Sunday 8000'
Sunday Night 7500'
Monday 8500'
Snoqualmie Pass Elevation
Saturday Night 11500'
Sunday 9000'
Sunday Night 8000'
Monday 6500'
Mt. Hood Elevation
Saturday Night 11500'
Sunday 10500'
Sunday Night 7500'
Monday 5500'

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

Previous forecast from Apr 26, 2023

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’.