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No winner this week. Here is my weekly weather quiz question for the last time. What is the average ratio of melted liquid to actual snowfall? In other words how much melted snow (liquid amount) will equal a specific amount of snow? Here is the correct answer. “Meteorologists developed a rule of thumb years ago that said ten inches (25 cm) of snow would melt down to 1 inch (2.5 cm) of water (or be the equivalent amount of rain if it fell as liquid), and that proportion was often used to determine the amount of equivalent precipitation from a snowfall. But that 10:1 ratio, we now know, is far from exact, and generally wrong across the breadth of conditions under which snow falls, even within an individual storm. When snow falls at air temperatures around freezing (32 oF / 0 oC), the ratio of snow to water equivalent comes close to the 10:1 ratio. However the full range is from around 100:1 to 3:1, depending on other weather factors such as air temperature, snow crystal structure and wind speed. In the United States, the ratio typically falls in the 8:1-20:1 range: the standard value used by the US National Weather Service for converting snowfall into liquid water equivalent when observers cannot melt down the gage-caught snow is 13:1.” I’ll have a new weekly weather quiz question for you starting Monday. Please remember to post your answer as a comment by clicking on “no comments /comments” in the upper right hand portion of this page under the caption, then add your comment. The first person to post the correct answer will win a week of free personalized weather forecasts tailored to your needs. The answer has to be a comment to win. An email answer will not count.
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Another upper level trough of low pressure has moved down from the Gulf of Alaska and will slowly push eastward over us. A frontal system slowly moved through Oregon on Thursday. Part of that storm moved through Northern California spinning precipitation into the area mainly between Roseburg and Medford. A new frontal system will be approaching the Pacific Northwest Christmas morning (position shown is Wednesday). Sorry, no white Christmas for the valleys only the mountains.
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Advisories: A WINTER STORM WARNING IS IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY EVENING ABOVE 2,000 FT. FOR EASTERN CURRY COUNTY COUNTY AND JOSEPHINE COUNTY. A WINTER STORM WARNING IS IN EFFECT FROM 4 AM UNTIL 10 PM SUNDAY FOR THE SOUTH OREGON CASCADES, THE SISKIYOUS MOUNTAINS, THE KLAMATH BASIN, NORTHERN AND EASTERN KLAMATH COUNTY, WESTERN, CENTRAL , AND EASTERN LAKE COUNTY.
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Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis: Mostly cloudy with showers today ( 0.10 in. of rain possible), showers tonight (0.25 in. of rain possible), rain Sunday (0.35 in. of rain possible), showers likely (60%) Sunday evening, a good (50%) chance of showers at night (0.10 in. of rain possible), a mix of clouds and sun with a slight (20%) chance of showers Monday AM, then mostly cloudy with a good (50%) chance of rain Monday night highs near 44 lows 35-33 warming to 37 Monday night. Mostly cloudy with rain Tuesday (Christmas Day) and Tuesday night, showers likely (60%) Wednesday, a good (50%) chance of showers Wednesday night through Thursday night, then mostly cloudy with a (30%) chance of showers Friday highs 45-42 lows 40-35. (seasonal averages high 45 low 33)
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Forecast for the Umpqua Basin including Roseburg: Mostly cloudy with rain and snow showers today (under 0.10 in. of rain possible, 1 in. of snow possible, snow level 2,000 ft.), evening rain and snow showers, rain and snow late tonight (0.15 in. of rain possible, 2 in. of snow possible, snow level 2,500 ft. falling to 2,000 ft), rain and snow Sunday (0.30 in. of rain possible, snow level 1,500 ft. rising to 2,000 ft. in the afternoon), rain and snow showers likely (70%) Sunday night (under 0.10 in. of rain possible), a slight (20%) chance of rain and snow showers Monday, then rain and snow likely (60%) Monday night highs near 40-44 lows 38-35 warming to 37 Monday night. Mostly cloudy with a good (50%) chance of rain and snow showers Monday, a slight (20%) chance of rain and snow Monday night, AM rain and snow likely (60%), AM rain and snow, rain Tuesday afternoon (Christmas Day), rain Tuesday night, rain and snow showers likely (60%) Wednesday and Wednesday night, a (40%) chance of rain and snow showers Thursday and Thursday night, then mostly cloudy with a slight (20%) chance of rain and snow showers Friday highs 46-42 lows 38-35. (seasonal averages high 47 low 36)
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Forecast for the South Oregon Coast including Coos Bay and North Bend: Mostly cloudy with AM coastal showers then showers and possible thunderstorms this afternoon with showers inland today (0.20 in. of rain possible, snow level 2,000 ft.), evening coastal showers and isolated thunderstorms then rain and isolated thunderstorms late tonight with evening showers then rain late at night inland ( 0.35 in. of rain possible), mostly cloudy with rain Sunday (0.40 in. of rain possible, AM snow level 2,000 ft.), coastal showers likely (70%) with inland evening showers then a good (50%) chance of showers late Sunday night (under 0.10 in. of rain possible, snow level 2,000 ft.), a (40%) chance of showers Monday, then rain likely (70%) Monday night highs near 46 lows 40-36. Mostly cloudy with rain Tuesday (Christmas Day) and Tuesday night, showers likely (70%) Wednesday and Wednesday night, a good (50%) chance of showers Thursday and Thursday night, then mostly cloudy with a (30%) chance of showers Friday highs near 49 lows 42-38. (seasonal averages high 51 low 40)
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Forecast for the Cascades of Lane County: Mostly cloudy with AM snow showers, rain and snow showers this afternoon (0.25 in. of rain possible, 1-2 in. of snow possible), rain and snow showers this evening, snow showers tonight (1-3 in. of snow possible), snow Sunday, snow showers Sunday night, a good (50%) chance of snow showers Monday, then mostly cloudy with a (40%) chance of snow Monday night snow level 2,500 ft. today and tonight, then at the surface Sunday through Monday night lows 29-24 warming to 28 Monday night highs 33-30. Mostly cloudy with rain and snow Tuesday (Christmas Day), and Tuesday night, rain and snow likely (60%) Wednesday and Wednesday night, mostly cloudy with a good (50%) chance snow showers Thursday and Thursday night, then mostly cloudy with a (30%) chance of snow showers Friday snow level 3,500 ft. Wednesday, at the surface Wednesday night and Thursday, then 2,500 ft. Thursday night and Friday highs 32-29 lows 29-24.
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**Because weather forecasting is a combination of science, intuition, and timing there can be no absolute guarantees that individual forecasts will be 100% accurate. Nature is in a constant state of flux and sudden unexpected weather events can happen.
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Get your local Eugene-Springfield news on-line at Eugene Daily News.com.
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