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No winner this week. Here is my weekly weather quiz question for the last time. What is an “Omega High?” Here is the correct answer. An “Omega High” is a warm high aloft which has become displaced and is on the polarward side of the jet stream. It frequently occurs in the late winter and early spring in the Northern Hemisphere. The name comes from its resemblance to the Greek letter, Omega, when analyzed on upper air charts. It is an example of a blocking high. It prevents storms rom moving in under the umbrella of the high. I’ll have a new weekly weather quiz question for you staring 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. Good luck.
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An upper level high pressure ridge (Shaded “Arch” shape) kept the rain away has moved to the east. An upper level trough of low pressure (Shaded “U” shape) is bringing back the rainy weather as it replaces the ridge. A cold front passed through Oregon overnight and is already cooling the temperatures behind it while surface high pressure (Blue “H” offshore) protects us from rain for Monday. What looks to be a strong frontal system (position shown is Wednesday) will move through Tuesday returning the chance of rain.
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Advisories: A FROST ADVISORY IS IN EFFECT FROM 1 AM UNTIL 8 AM MONDAY FOR THE NORTH OREGON COAST AND THE SOUTH CENTRAL OREGON COAST.
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Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis: Partly cloudy with patchy fog late tonight and Monday AM, mostly sunny in the afternoon, a good (50%) chance of rain late Monday night (0.10 in. of rain possible), mostly cloudy with rain Tuesday (0.50 in. of rain possible), cloudy with evening showers likely (70%), a good (50%) chance of showers Tuesday night (0.25 in. of rain possible), mostly cloudy with a good (50%) chance of AM showers, then showers likely (70%) Wednesday afternoon and Wednesday night lows 33-39 highs 54-48. Mostly cloudy with a good (50%) chance of showers Thursday, a (30%) chance of showers at night, partly cloudy Friday through Saturday night, then mostly cloudy with a slight (20%) chance of rain Sunday highs 50-55 lows near 38. (seasonal averages high 54 low 36)
Forecast for the Umpqua Basin including Roseburg: Mostly clear with patchy fog late tonight, partly cloudy with patchy AM fog and freezing fog Monday AM, sunny in the afternoon, partly cloudy in the evening, mostly cloudy with a (40%) chance of rain at night (under 0.10 in. of rain possible), rain Tuesday (0.30 in. of rain possible), showers Tuesday night (0.15 in. of rain possible), rain and snow showers Wednesday, then rain and snow showers likely (70%) Wednesday night lows 33-39 cooling to 35 Wednesday night highs 59-50. Mostly cloudy with rain and snow showers likely (60%) Thursday, a (30%) chance of showers Thursday night, partly cloudy Friday through Saturday night, then mostly cloudy with a slight (20%) chance of rain Sunday highs 49-58 lows 36-38. (seasonal averages high 56 low 38)
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Forecast for the South Oregon Coast including Coos Bay and North Bend: Mostly clear tonight sunny Monday, mostly cloudy with a (40%) chance of evening rain, rain late at night (0.25 in. of rain possible) and Tuesday (0.75 in. of rain possible), evening coastal showers with a showers and a slight (20%) chance of thunderstorms late Tuesday night while just showers late at night inland (0. 30 in. of rain possible), showers and slight (20%) chance of thunderstorms Wednesday, then showers likely (60%) Wednesday night lows 35-42 cooling to 36 Wednesday night highs 53-46. Mostly cloudy with showers likely (60%) Thursday, a good (50%) chance of showers Thursday night, partly cloudy Friday and at night, mostly cloudy Saturday, then mostly cloudy with a slight (20%) chance of rain Saturday night and Sunday highs 49-54 lows 38-42. (seasonal averages high 54 low 41)
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Forecast for the Cascades of Lane County: Clear tonight, mostly sunny and just a bit warmer Monday, partly cloudy in the evening, mostly cloudy with a good (50%) chance of rain and snow late Monday night (under 0.10 in. of rain possible), rain and snow Tuesday, rain and snow showers Tuesday night, rain and snow showers Wednesday, then rain and snow showers likely (70%) Wednesday night free air freezing level 3,500 ft. falling to the surface late tonight, 5,000 ft. rising to 6,500 ft. Monday afternoon, snow level 5,500 ft. Monday night, 3,500 ft. Tuesday, then 3,000 ft. Tuesday night through Wednesday night lows 24-28 cooling to 22 Wednesday night highs 47-33. Mostly cloudy with snow showers likely (60%) Thursday, a good (50%) chance of rain and snow showers Thursday night, a mix of clouds and sun with a slight (20%) chance of rain and snow showers Friday, just partly cloudy Friday night, a mix of clouds and sun Saturday, mostly cloudy Saturday night, then mostly cloudy with a slight (20%) chance of rain Sunday snow level at the surface Thursday, 3,000 ft. Thursday night and Friday, free air freezing level 5,500 ft. Friday night, 6,000 ft. Saturday, 7,000 ft. Saturday night, then snow level 6,000 ft. Sunday highs 34-44 lows 24-30.
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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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