A weak upper low is diving south into Oregon this morning and spinning up light bands of precipitation from south to north over the Mt Hood area, the southern Washington Cascades and southern Olympics. These areas will see periods of light snow that peter out during the day. Areas that saw strong SE winds overnight like Crystal Mt and Snoqualmie Pass, will see those winds diminish quickly this morning as ridgeline winds become WSW. Those same areas saw an impressive drop in temperatures at 5000', some areas are 15F colder than yesterday morning. Snow levels and temperatures will slightly warmer west of the Cascade crest today for areas like Mt Baker and over the Olympics.
We'll see a few showers continue tonight, especially over the west central and west north zones as the upper longwave trough passes through. A much stronger frontal system will approach the area on Friday. Light warm frontal precipitation will begin in most areas in the afternoon, becoming more moderate in some areas before sunset. A bigger story will be the winds that ramp up in advance of this system, becoming strong in many areas out of the S or SE.
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
Cloudy with periods of light snow or rain. Light to occasionally moderate ridgeline winds.
Thursday
Night
Cloudy with scattered light snow showers. Light to occasionally moderate ridgeline winds increasing after midnight.
Thursday
Cloudy. Light to occasionally moderate ridgeline winds.
Thursday
Night
Cloudy with scattered light snow showers. Light to occasionally moderate ridgeline winds.
Thursday
Cloudy. Light to moderate ridgeline winds decreasing later this morning.
Thursday
Night
Cloudy with scattered light snow showers. Light to occasionally moderate ridgeline winds increasing after midnight.
Thursday
Cloudy with periods of light snow. Moderate ridgeline winds decreasing later this morning.
Thursday
Night
Cloudy with scattered light snow showers. Light to occasionally moderate ridgeline winds.
Thursday
Cloudy with a chance of light snow. Light to moderate E-SE ridgeline winds becoming light WSW in the afternoon. Light to moderate E Pass level winds becoming light in the afternoon.
Thursday
Night
Cloudy with scattered light snow showers. Light W ridgeline winds. Light to moderate E winds at Pass level.
Thursday
Cloudy with a chance of light snow. Moderate E-SE ridgeline winds becoming light WSW in the afternoon. Moderate E Pass level winds becoming light in the afternoon.
Thursday
Night
Cloudy with scattered light snow showers. Light W ridgeline winds. Light to moderate E winds at Pass level.
Thursday
Cloudy. Light to occasionally moderate ridgeline winds.
Thursday
Night
Cloudy with a slight chance of light snow showers. Light to occasionally moderate ridgeline winds.
Thursday
Cloudy with periods of light snow. Light to occasionally moderate ridgeline winds.
Thursday
Night
Cloudy with a slight chance of light snow showers. Light to occasionally moderate ridgeline winds.
Thursday
Cloudy with periods of light snow. Light to occasionally moderate ridgeline winds.
Thursday
Night
Cloudy with a slight chance of light snow showers. Light to occasionally moderate ridgeline winds.
Thursday
Cloudy with light snow in the morning, then scattered snow showers in the afternoon. Light to occasionally moderate ridgeline winds.
Thursday
Night
Cloudy with scattered light rain and snow showers. Light ridgeline winds increasing after midnight.
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).