Check out my latest Eugene Daily News Weather Or Not column:
http://eugenedailynews.com/2018/04/it-was-their-month-in-history-but-why-didnt-we-know-about-them/
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Here is my weekly weather quiz question for the last time. What is “Differential Motion?” Here is the correct answer. Differential Motion is cloud motion that appears to differ relative to other nearby cloud elements, e.g. clouds moving from left to right relative to other clouds in the foreground or background. Cloud rotation is one example of differential motion, but not all differential motion indicates rotation. For example, horizontal wind shear along a gust front may result in differential cloud motion without the presence of rotation. I’ll have a new weekly weather quiz question for you starting Monday. The first person to post the correct answer as a comment on this page will win a week of free personalized weather forecasts tailored to your needs. Good luck.
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An Upper Level Low Pressure Trough (Shaded “U” shape with arrows) is still sending us storms. The graphics for days 1-3 show a warm front that moved through Friday and the next front that pushes in by late today. The graphics for days 3-7 show the frontal systems that will move through the Pacific Northwest tonight and Sunday. Then a frontal system moves inland from the Oregon and California coasts next Wednesday and Friday, and next Saturday.
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Air Quality Index:
Eugene/Springfield: The Air Quality Index is 32 in the Good category measuring Particulate Matter.
Oakridge: The Air Quality Index is 44 in the Good category measuring Particulate Matter.
Cottage Grove: The Air Quality Index is 33 in the Good category measuring Particulate Matter.
Data courtesy of Lane Regional Air Protection Agency (LRAPA)
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Advisories:
- A PERMANENT HEALTH ADVISORY REMAINS IN EFFECT FOR THE SOUTH UMPQUA RIVER BAR. POOLS IN THE BEDROCK ALONG THE RIVERS EDGE ARE KNOWN TO DEVELOP BLUE-GREEN ALGAE (CYANOBACTERIAL) BLOOMS THAT CAN BE HARMFUL TO PETS AND PEOPLE IF ACCIDENTAL INGESTION OCCURS. SIGNS HAVE BEEN POSTED ALONG SEVERAL ACCESS AREAS ALONG THE RIVER.
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Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis:
- Cloudy and a bit warmer with a slight (20%) chance of rain today, increasing clouds to mostly cloudy with rain tonight (0.50 in. of rain possible) and Sunday AM, showers and a bit cooler in the afternoon, showers likely (70%) and colder Sunday night,
- Mostly cloudy with AM showers likely (70%), showers with a slight (20%) chance of thunderstorms and a bit cooler Monday afternoon, evening showers likely (70%) with a slight (20%) chance of thunderstorms (small hail possible), showers likely (70%) late Monday night.
- highs 60-50 lows 45-38.
- Mostly cloudy and a bit warmer with a good (50%) chance of showers Tuesday, cloudy with a (40%) chance of showers Tuesday night,
- Mostly cloudy with a (30%) chance of showers and a bit warmer Wednesday and at night,
- A mix of clouds and sun with a (30%) chance of showers and a bit warmer Thursday, partly cloudy Thursday night,
- Then a mix of clouds and sun and a bit warmer Friday.
- highs 53-63 lows near 38. (seasonal averages high 60 low 39)
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Eugene-Springfield Pollen Count
Grass………. Low (0)
Trees………. Very High (755)
Last Counted: 4/7/18
Data Courtesy of Oregon Allergy Associates.
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Forecast for Roseburg:
- Mostly cloudy with a slight (20%) chance of rain and a bit warmer today, a good (50%) chance of evening rain, rain late tonight (0.25 in. of rain possible),
- Mostly cloudy and a bit cooler with rain Sunday (o.50 in. of rain possible, afternoon snow level 3,000 ft.), rain and snow showers likely (70%) at night (0.10 in. of rain possible, snow level 3,000 ft. falling to 2,500 ft. late at night),
- AM rain and snow showers, mostly cloudy and a bit cooler with showers and snow showers with a slight (20%) chance of thunderstorms Monday afternoon, then rain and snow showers likely (60%) Monday night.
- highs 62-52 lows 45-38.
- Mostly cloudy with a (40%) chance of rain and snow showers and a bit warmer Tuesday, a slight (20%) chance of showers at night,
- Cloudy and a bit warmer with a (30%) chance of showers Wednesday, mostly cloudy with a (30%) chance of showers Wednesday night,
- Partly cloudy with a slight (20%) chance of showers and a bit warmer Thursday, just partly cloudy at night,
- Then mostly cloudy and a bit warmer Friday.
- highs 55-64 lows near 40. (seasonal averages high 62 low 42)
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Forecast for The South Oregon Coast Including Coos Bay and North Bend:
- Cloudy with a (30%) chance of rain and a bit cooler today (under 0.10 in. of rain possible), rain tonight (0.50 in. of rain possible) and Sunday (a bit cooler, 0.25 in. of rain possible), evening coastal showers likely (60%) with coastal showers likely (70%) with a slight (20%) chance of thunderstorms late Sunday night while inland showers likely (70%) at night (0.10 in. of rain possible),
- Mostly cloudy and a bit cooler with showers and a slight (20%) chance of thunderstorms Monday, then showers likely (70%) at night.
- highs 56-50 lows 46-40.
- Mostly cloudy with a (30%) chance of showers and a bit warmer Tuesday, a slight (20%) of showers Tuesday night,
- A (30%) chance of showers and a bit warmer Wednesday and at night,
- Partly cloudy and a bit warmer with a slight (20%) chance of showers Thursday, just partly cloudy Thursday night,
- Then mostly cloudy and a bit warmer Friday.
- highs 52-58 lows near 42. (seasonal averages high 55 low 43)
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Forecast for the Cascades in Lane County:
- Mostly cloudy and a bit warmer today, a good (50%) chance of evening rain and snow, rain and snow late tonight (0.25 in. of rain possible, 2 in. of snow possible),
- AM rain and snow, rain and snow showers and a bit cooler Sunday afternoon (2-5 in. of snow possible), evening rain and snow showers, snow showers and a bit colder late Sunday night (1-3 in. of snow possible),
- Snow showers and a bit cooler Monday (1-3 in. of snow possible), snow showers likely (70%) at night.
- snow level free air freezing level 5,500 ft. rising to 6,500 ft. this afternoon, snow level 5,000 ft. tonight, 4,500 ft. Sunday, 3,500 ft. falling to 2,500 ft. late Sunday night, then 2,500 ft. Monday and Monday night.
- highs 47-32 lows 32-25.
- A mix of clouds and sun and a bit warmer with a good (50%) chance of snow showers Tuesday, cloudy with a good (50%) chance of rain and snow showers Tuesday night,
- Mostly cloudy with a (40%) chance of rain and snow showers and a bit warmer Wednesday and at night,
- A mix of clouds and sun with a (30%) chance of rain and snow showers and a bit warmer Thursday, just partly cloudy Thursday night,
- Then a mix of clouds and sun and a bit warmer Friday.
- snow level 2,500 ft. Tuesday, 3,500 ft. Tuesday night and Wednesday, 5,000 ft. Wednesday night, 4,000 ft. Thursday, then free air freezing level 5,500 ft. Thursday night and Friday.
- highs 37-53 lows near 26.
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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 and Lane County news on-line at eugenedailynews.com.
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