Mountain Weather Forecast

Weather Synopsis

An upper-level ridge of high pressure continues to dominate the weather through Wednesday night. Moderate E winds in the early evening should ease as the surface high weakens and shifts east.  A low and associated shortwave trough move into the region Thursday through Friday. High cloud cover and light southerly winds aloft represent the precursors and should help moderate overnight temperatures slightly. Temperatures will not be quite as chilly as Tuesday night for most locations. The low moves into the Oregon near-shore waters on Thursday, bringing lowering clouds followed by light rain snow to NW Washington as a fading warm front spreads a band of precipitation onshore. Periods of light rain and snow should fill into other areas during the afternoon. Light E flow at low levels likely keeps Snoqualmie Pass just cool enough for all snow, but a mix with rain is possible Thursday afternoon.

Thursday night, the low spins just off the Oregon Coast, and the upper trough moves onshore, bringing the strongest precipitation of the storm. Expect moderate rain and snow to locations from around Snoqualmie Pass southward. Snowfall should be the most significant on the southern Cascade Volcanoes. Southerly ridgeline winds will also peak in the moderate range for these same locations. Rain and snow decrease from north to south Thursday night through Friday, but linger much of the day in the southern Cascades Volcanoes. Expect partly cloudy skies developing late in the day for the Mt. Baker and Hurricane Ridge areas.

Storm total snowfall of 8-14" is likely for Paradise while Mt. Hood can expect 8-12" above 6000 ft. Snoqualmie pass could pick up 1-5" of snow from this event with marginal temperatures at pass level limiting snowfall amounts.