A weak front passed through Monday night. In its wake, we have post-frontal showers across the area, heaviest along the west slopes of the Cascades from about Hwy 20 West and south. Moderate showers can be found along the western portions of I-90 and up near a convergence zone over western Skagit and Snohomish counties. As weak upper level ridging builds offshore, showers should become more scattered and lighter for all areas by late morning. That said, expect clouds to hang around all day below 10,000' while the highest peaks should pop out of the clouds. After several days of warm weather, snow levels have fallen to 4000-5000' this morning and will slide a bit lower through the afternoon hours. Moderate westerly winds, except strong down at Mt Hood this morning, will also decrease during the day.
Stray showers will hang around Tuesday night along with cloud cover. On Wednesday, a ridge of high pressure will attempt to build offshore, shunting warm frontal precipitation to our north. Most forecast models hold off precipitation until Wednesday night as the ridge collapse, but we could see light rain and snow move into the Mt Hood area and Olympics before the end of the day. Snow levels will hold steady on Wednesday over the Washington Cascades but look for a significant warm-up Wednesday night as the storm takes aim at the region.
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
Cloudy with light scattered rain and snow showers. Showers decreasing in the afternoon.
Tuesday
Night
Cloudy.
Tuesday
Cloudy with light scattered rain and snow showers. Showers decreasing in the afternoon.
Tuesday
Night
Cloudy. Chance of showers early.
Tuesday
Light to moderate rain and snow showers, the heaviest showers west part near the convergence zone this morning. Cloudy with scattered showers in the afternoon.
Tuesday
Night
Cloudy. Chance of showers early.
Tuesday
Cloudy with light to occasionally moderate rain and snow showers this morning. Showers becoming scattered mid-day and decreasing in the afternoon.
Tuesday
Night
Mostly cloudy. Chance of showers early.
Tuesday
Cloudy with light rain and snow showers this morning. Showers becoming scattered mid-day and decreasing in the afternoon. Light to moderate west winds at Pass level and ridgeline.
Tuesday
Night
Cloudy. Chance of showers early. Light west wind becoming variable at Pass level.
Tuesday
Light to occasionally moderate rain and snow showers this morning. Showers becoming scattered mid-day and decreasing in the afternoon. Light to moderate west winds at Pass level and moderate at ridgeline.
Tuesday
Night
Cloudy. Chance of showers early. Light west wind becoming variable at Pass level.
Tuesday
Cloudy with scattered light rain and snow showers mainly near the Cascade crest this morning, then mostly cloudy in the afternoon.
Tuesday
Night
Mostly cloudy.
Tuesday
Cloudy with light rain and snow showers, occasionally moderate near the Cascade crest this morning, then cloudy with isolated light showers in the afternoon. Moderate to strong ridgeline winds.
Tuesday
Night
Mostly cloudy.
Tuesday
Cloudy with light rain and snow showers mainly near the Cascade crest this morning, then cloudy with isolated light showers in the afternoon. Moderate to strong ridgeline winds.
Tuesday
Night
Mostly cloudy.
Tuesday
Cloudy with light rain and snow showers this morning, then mostly cloudy with isolated showers in the afternoon. More sunshine east side of the mountain. Strong ridgeline winds decreasing in the afternoon.
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).