Most areas picked up another few inches overnight, making storm totals of over 2ft in the SW quarter of the region, and a foot or more for other west side zones and passes with 6-12" on the east side. Snow showers continue to rotate ashore ahead of a cold Low on SW flow this morning. Temperatures are a couple degrees colder than yesterday, and winds have ratcheted down but they're still blowing, especially at Mt Hood.
Expect another cool, wintry day with more chances of sun breaks further east. Afternoon instability may lend itself to heavier showers and isolated chances for thunder snow. Once again, the heavier snowfall amounts are expected for the SW volcanoes with less snow further north and east. A weak convergence band may also enhance snowfall amounts this afternoon into the evening for the central Cascades.
Overnight, showers should taper off substantially. We'll start the week with a chilly morning, temperatures could even be a little colder than this morning. During the day we're likely to see more sunshine between the isolated showers. Look for a switch to NW flow and a bump in wind speeds at ridgelines during the day.
Cloudy with light to moderate snow showers. Snowfall could be heavier in the afternoon with possible convergence zone formation.
Sunday
Night
Scattered, light snow showers.
Sunday
Cloudy with breaks of sun possible further east. Snow showers could be heavier at times mainly near the volcanoes. SW winds becoming W light to moderate.
Sunday
Night
Scattered snow showers, becoming lighter and intermittent.
Sunday
Scattered snow showers, could be heavier in the afternoon. Chances for breaks of sun between showers. Light winds through the pass, light to moderate ridgeline winds.
Sunday
Night
Scattered light snow showers, tapering. Light winds through the pass, light to moderate ridgeline winds.
Sunday
Scattered snow showers, could be heavier at times. Chances for breaks of sun between showers. Light winds through the pass, light to moderate ridgeline winds.
Sunday
Night
Scattered light snow showers, tapering. Light winds through the pass, light to moderate ridgeline winds.
Sunday
Broken skies becoming partly to mostly cloudy. Scattered, light showers near the crest.
Sunday
Night
Scattered light snow showers with a clearing trend.
Sunday
Broken skies becoming mostly cloudy, with light to moderate snow showers at times. Light to moderate ridgeline winds.
Sunday
Night
Scattered light snow showers with a clearing trend.
Sunday
Light to moderate snow showers with breaks of sun, especially further east.
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).