The upper airflow(look at the little arrows along the coast) is “zonal” meaning straight lie west to east bringing warmer more moist air into Oregon. A frontal system is pushing into northern California (see last frame of animation). It is spreading moisture northward over us. Freezing rain and sleet are falling in the area because of that warm moist rolling over the cold air mass that is still over us.

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Advisories: A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE NORTH OREGON COAST  UNTIL 10 PM TONIGHT,   ANOTHER IS IN EFFECT UNTIL 6 AM SUNDAY FOR THE NORTH COAST RANGE.   A WINTER STORM WARNING  IS IN EFFECT  UNTIL 6 AM SUNDAY FOR THE PORTLAND AREA AND THE COLUMBIA GORGE AREA. A WINTER STORM WARNING IS IN EFFECT  UNTIL 10 PM TONIGHT FOR THE SALEM AREA., ANOTHER WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 6 AM SUNDAY FOR THE NORTH CASCADE FOOTHILLS , AND ANOTHER UNTIL 6 AM SUNDAY FOR THE FOOTHILLS OF THE NORTH CASCADES,

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For the Willamette Valley: . AM rain and light freezing rain likely (60%) this morning then turning to rain likely in the afternoon high 36-38. Saturday night and Sunday will be warmer with rain low 33-35 high 38-43. Mostly cloudy with a good (50%) chance of showers Sunday night lows 33-35. Mostly cloudy with a (50%) chance of rain Monday high 44-47. Monday night through Wednesday highs warming from 44-50 lows 34-39. A good chance (50%) of rain Wednesday night low near 40. There will be a chance of showers Thursday through Friday highs near 50 lows near 40.

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For the Umpqua Basin: Cloudy with rain this morning and rain likely (70% in the afternoon) high 42-45, tonight evening rain likely changing to showers after midnight. low 35-39. After AM showers likely Sunday morning then a (60%) chance of showers in the afternoon, snow level 2,000? in the afternoon high 42-44, There will be a (30%) chance of showers at night low 34-36.There will be  rain Monday with rain likely at night high 45 low 40. Rain and windy Tuesday and Tuesday night high 50 low 42-44. Rain will be likely (60%) Wednesday through Friday highs in the upper 40s to low 50s lows in low 40s.

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Forecast for the South Coast: Today rain and fog in the morning then showers likely (60%) this afternoon  high 48-50 then  rain likely (60%) this evening changing to showers after midnight low 37-40. Showers likely (60%) Sunday morning with a chance of showers (50%) in the afternoon, Sunday night a (30%) chance of  showers, high 46-50 low near 40. Rain (70-80%) Monday through Friday highs warming to the low to mid 50s lows low to mid 40s.

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For the Cascades: Today snow and rain (1-3″ of snow) snow level at the surface. Tonight snow and freezing rain(1-3″ of snow) snow level at the surface in the afternoon, Sunday snow likely, snow level at the surface (1-4″ of snow) . Sunday night snow level at the surface Monday through Friday the snow level will stay at or near pass levels, but rise to 6,500′ Thursday night and Friday,