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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 continuing the showers and a new frontal system is approaching the California coast to bring more wet weather for Christmas. Sorry, no white Christmas for the valleys only the mountains.
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Advisories: A WINTER STORM WARNING IS IN EFFECT FROM THROUGH 10 PM TODAY ABOVE 2,000 FT. FOR CENTRAL DOUGLAS COUNTY, THE EASTERN DOUGLAS COUNTY FOOTHILLS, EASTERN CURRY COUNTY COUNTY AND JOSEPHINE COUNTY, AND JACKSON COUNTY. A WINTER STORM WARNING IS IN EFFECT UNTIL 10 PM TONIGHT FOR THE SOUTH CENTRAL OREGON CASCADES, THE SOUTH OREGON CASCADES, AND THE SISKIYOUS MOUNTAINS. A WINTER STORM WARNING IS IN EFFECT FROM 4 AM UNTIL 10 PM TODAY FOR THE KLAMATH BASIN, NORTHERN AND EASTERN KLAMATH COUNTY, WESTERN, CENTRAL , AND EASTERN LAKE COUNTY.
A FLOOD WARNING CONTINUES FOR THE COQUILLE RIVER AT COQUILLE. MINOR FLOODING IS OCCURRING AS WAS EXPECTED. FOR MORE DETAILS GO TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE AT PORTLAND FLOOD WARNING PAGE.
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Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis: Mostly cloudy with showers today (0.25 in. of rain possible), showers this evening and late tonight (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 (40%) chance of rain late Monday night (0.15 in. of rain possible), rain Tuesday (Christmas Day) and Tuesday night highs near 44 lows 35-34-38. Mostly cloudy with showers likely (70%) Wednesday and Wednesday night, mostly cloudy with a good (50%) chance of showers Thursday and Thursday night, a (30%) chance of showers Friday, then mostly cloudy with a slight (20%) chance of showers Friday night, then just mostly cloudy Saturday highs near 43 lows 36-34. (seasonal averages high 45 low 33)
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Forecast for the Umpqua Basin including Roseburg: Mostly cloudy with showers and snow this AM, rain and snow this afternoon (0.35 in. of rain possible, 3-5 in. of snow possible, snow level 2,000 ft.), rain and snow likely (60%) this evening, scattered rain and snow showers late tonight (under 0.10 in. of rain possible), just mostly cloudy Monday, then a good (50%) chance of rain and snow late Monday night (under 0.10 in. of rain possible), AM rain and snow, rain Tuesday afternoon (Christmas Day) and in the evening, then showers late Tuesday night highs near 42-45 lows 36-38. Mostly cloudy with rain and snow showers Wednesday, rain and snow showers likely (60%) Wednesday night, a (40%) chance of rain and snow showers Thursday, a slight (20%) chance of rain and snow showers Thursday night and Friday, then just mostly cloudy Friday night and Saturday highs near 43 lows 35-30. (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 coastal showers and a slight (20%) chance of thunderstorms this AM while AM showers and rain this afternoon (0.50 in. of rain possible, snow level 2,000 ft.), coastal evening rain likely (70%) and showers likely (70%) late while evening rain then scattered showers late tonight inland (under 0.10 in. of rain possible, snow level 2,000 ft. late), mostly cloudy Monday, cloudy with a slight (20%) chance of evening rain, rain likely (60%) late Monday night (0.20 in. of rain Monday night), mostly cloudy with rain Tuesday (Christmas Day) and Tuesday night highs 46-50 lows 37-42. Mostly cloudy with showers Wednesday, showers likely (60%) Wednesday night, a good (50%) chance of showers Thursday, then mostly cloudy with a slight (20%) chance of showers Thursday night through Saturday highs near 48 lows 38-34. (seasonal averages high 51 low 40)
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Forecast for the Cascades of Lane County: Mostly cloudy with snow showers today (3-6 in. of snow possible), snow showers tonight (1-3 in. of snow possible), a good (50%) chance of snow showers Monday AM, a slight (20%) chance of snow showers in the afternoon, a good (50%) chance of snow late Monday night, mostly cloudy with rain and snow Tuesday (Christmas Day) and Tuesday night snow level at the surface today through Monday, free air freezing level at the surface in the evening, back to snow level at the surface Monday night, 2,500 ft. Tuesday, then 4,000 ft. Tuesday night highs 33-30 warming to 33 Tuesday lows 24-27. Mostly cloudy with rain and snow showers likely (60%) Wednesday, snow showers likely (60%) Wednesday night, mostly cloudy with a good (50%) chance snow showers Thursday and Thursday night, a (30%) chance of snow showers Friday, then mostly cloudy with a slight (20%) chance of snow showers Friday night and Saturday snow level 3,000 ft. Wednesday, at the surface Wednesday night and Thursday, 2,500 ft. Thursday night, at the surface Friday, 2,500 ft. Friday night, then at the surface Saturday highs near 30 lows 22-25.
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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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