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Sorry, no winner this week. Here is my weekly weather quiz question for the last time. What is a “halo?” Here is the correct answer. Sun dogs, halos, and rainbows are all due to the same basic physics: refraction of sunlight through moisture in the atmosphere. Refraction is the bending of light as it passes through a material, such as the lenses of your glasses. The difference between halos and rainbows is two-fold: the shape and the material that the light refracts through. To form a rainbow, light refracts through and reflects from a drop of water in the atmosphere which is approximately spherical. On the other hand, a halo forms from refraction through a hexagonal crystal of ice. The angle through which light refracts depends on the surface and material it refracts through, so the angle between the sun and the light phenomenon we see in the sky is different for rainbows and halos. 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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A high pressure ridge (shaded “Arch” shape) turned our airflow more from over the ocean (the term for that is flattening as it looses it’s hump), for more rain chances because it is pumping subtropical moisture into the Pacific Northwest. Since the moisture feed is coming from Hawaii it is nick-named “The Pineapple Express”. Behind the ridge is an upper level low (shaded “U” shape on previous graphic). A frontal system has moved in and the next frontal system behind it (warm front first) will push through next. A parade of frontal systems will enhance this weather pattern for your workweek including Halloween. Prepare your Trick-or-Treaters for the wet weather.
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Forecast for the Umpqua Basin including Roseburg: Mostly cloudy with rain this evening, rain likely (60%) late tonight (0.10 in. of rain possible), rain likely (70%) Monday (0.10 in. of rain possible), Monday night (under 0.10 in. of rain possible), Tuesday (0.10 in. of rain possible) and Tuesday night (0.15 in. of rain possible), rain Wednesday and Wednesday evening, then showers and colder Wednesday night (Halloween) lows 55-48 highs 68-60. Cloudy with showers likely (60%) Thursday AM, a god (50%) chance of showers in the afternoon, mostly cloudy with a (30%) chance of showers Thursday night, just mostly cloudy Friday and Friday night, mostly cloudy with a slight (20%) chance of rain Saturday, and Saturday night, then mostly cloudy with a slight (20%) chance of rain Sunday highs 58-65 lows 43-47. (seasonal averages high 61 low 43)
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Forecast for the South Oregon Coast including Coos Bay and North Bend: Mostly cloudy with rain and patchy coastal fog late tonight and Monday AM, evening rain inland and rain likely (60%) late tonight (0.30 in. of rain possible) and Monday (0.30 in. of rain possible), rain likely (60%) Monday night (0.20 in. of rain possible), coastal rain Tuesday AM, rain likely (60%) inland and rain in the afternoon (0.75 in. of rain possible), rain Tuesday night (0.65 in. of rain possible) through Wednesday evening, then showers late Wednesday night (Halloween) lows 56-50 highs 62-58. Cloudy with AM showers likely (60%) and a good (50%) chance of showers Thursday afternoon, mostly cloudy with a (40%) chance of showers Thursday night, just mostly cloudy Friday and Friday night, mostly cloudy with a slight (20%) chance of rain Saturday, a (30%) chance of rain Saturday night, then mostly cloudy with a slight (20%) chance of rain Sunday highs 57-62 lows near 48. (seasonal averages high 59 low 45)
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Forecast for the Cascades of Lane County: Mostly cloudy with rain tonight (0.75 in. of rain possible), rain Monday (0.25 in. of rain possible), rain likely (60%) Monday night (0.25 in. of rain possible) and Tuesday (0.25 in. of rain possible), rain Tuesday night and Wednesday, then mostly cloudy with showers Wednesday night snow level above 8,000 ft. tonight through Tuesday night, then 7,000 ft. Wednesday and Wednesday night (Halloween) lows 42-32 highs 52-55 cooling to 48 Wednesday. Mostly cloudy with showers likely (60%) Thursday, a good (50%) chance of showers Thursday night, a mix of clouds and sun with a slight (20%) chance of showers Friday, just mostly cloudy Friday night, mostly cloudy with a good (50%) chance of rain Saturday, cloudy with a good (50%) chance of rain Saturday night, then a mix of clouds and sun with a slight (20%) chance of rain Sunday snow level 6,500 ft. Thursday and Thursday night, 7,000 ft. Friday, free air freezing level 9,000 ft. Friday night, snow level 7,500 ft. Saturday, 7,000 ft. Saturday night, then 7,500 ft. Sunday highs 43-52 lows 30-33.
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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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