Here is my weekly weather quiz question. What is “Attenuation?”   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 High Pressure Ridge (Shaded “Arch” shape with blue arrows) took over returning producing sunny skies and warm temperatures. The graphics for days 1-3 show the next frontal system that will approach the Pacific Northwest tonight and Thursday. An Upper Level Low Pressure Trough (Shaded “U” shape with blue arrows) will move out of the Gulf of Alaska behind the frontal system to keep the rain chances with us. The graphics for days 3-7 show no frontal systems pushing into or through the Pacific Northwest through next Wednesday.

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Air Quality Index:

Eugene-Springfield: The Air Quality Index is 14 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 21 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 5 in the Good category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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Home Wood Heating Advisory:

Eugene-Springfield: GREEN – Burning is Allowed.

Oakridge: GREEN – Burning is Allowed.

*Note: Pellet stoves may be used anytime if they produce no visible emissions.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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Advisories:

• Permanent Health Advisory remains in effect for the South Umpqua River and Lawson 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:

• Mostly sunny today, partly cloudy this evening, increasing clouds to mostly cloudy with a slight (20%) chance of showers late tonight (under 0.10 in. of rain possible),
• Mostly cloudy with AM rain, showers and much cooler Thursday afternoon (0.25 in. of rain possible), showers likely (60%) and colder Thursday night (0.10 in. of rain possible),
• Mostly cloudy with showers likely (60%) and a slight (20%) chance of thunderstorms Friday afternoon and evening, then showers likely (70%) at night.
• highs 73-58 lows 52-42.
• Mostly cloudy with showers likely (60%) and a bit cooler Saturday, cloudy with a good (50%) chance of showers Saturday night,
• Mostly cloudy with a good (50%) chance of showers Sunday (Mother’s Day), cloudy with a good (50%) chance of showers at night,
• Mostly cloudy with showers likely (70%) Monday, a good (50%) chance of showers at night,
• Then showers likely (70%) Tuesday.
• highs near 58 lows 42-45. (seasonal averages high 66 low 43)

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Eugene-Springfield Pollen Count:

Grass………. Moderate (12)

Trees………. Moderate (54)

Last Counted: 5/9/17

Data Courtesy of Oregon Allergy Associates.

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Forecast for Roseburg:

• Sunny today, partly cloudy this evening, increasing clouds to mostly cloudy with a (30%) chance of rain late tonight,
• Mostly cloudy and colder with rain Thursday, evening showers, showers likely (70%) and much cooler late at night and Friday AM, then showers and a bit cooler in the afternoon and Friday night.
• highs 78-58 lows 52-44.
• Mostly cloudy with showers and a bit cooler Saturday, a (30%) chance of showers Saturday night and (a bit warmer) Sunday (Mother’s Day), showers likely (60%) Sunday night and Monday, mostly cloudy with a (40%) chance of showers Monday night,
• Then showers likely (60%) and a bit cooler Tuesday.
• highs 56-62 cooling to 58 Tuesday lows 42-45. (seasonal averages high 69 low 46)

 

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Forecast for The South Central Oregon Coast Including Coos Bay and North Bend:

• Mostly cloudy with patchy coastal fog this AM and sunny this afternoon while sunny inland today, becoming mostly cloudy with rain likely (70%) tonight (under 0.10 in. of rain possible),
• Mostly cloudy and a bit cooler with rain Thursday (0.25 in. of rain possible), coastal showers at night while inland evening showers with inland showers likely (70%) late at night (0.25 in. of rain possible),
• Mostly cloudy with showers and a bit cooler Friday and Friday night.
• highs 62-55 lows 50-47.
• Mostly cloudy with showers likely (60%) Saturday, a (40%) chance of showers Saturday night and (a bit warmer) Sunday (Mother’s Day), then showers likely (70%) Sunday night through Tuesday (a bit cooler).
• highs 55-58 cooling to 56 Tuesday lows 43-46. (seasonal averages high 58 low 46)

 

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Forecast for the Cascades in Lane County:

• Mostly sunny this AM, becoming partly cloudy with a slight (20%) chance of showers this afternoon, a slight (20%) chance of evening showers and thunderstorms, mostly cloudy with a slight (20%) chance of showers late tonight,
• Mostly cloudy with rain and colder Thursday, rain and snow showers likely (70%) and colder at night,
• AM rain and snow showers likely (70%), rain and snow showers likely (70%) and a slight (20%) chance of thunderstorms and a bit cooler Friday afternoon and evening, then rain and snow showers likely (70%) Friday night.
• snow level above 8,000 ft. today and tonight, 6,500 ft. Thursday, 4,500 ft. Thursday night, then 4,000 ft. Friday and Friday night.
• highs 68-42 lows 38-28.
• Rain and snow showers likely (70%) Saturday and Saturday night,
• A mix of clouds and sun and a bit warmer with a (40%) chance of showers Sunday (Mother’s Day), mostly cloudy with a good (50%) chance of rain and snow showers at night,
• Mostly cloudy with rain and snow showers likely (70%) Monday through Tuesday (a bit cooler).
• snow level 3,500 ft. Saturday, 4,500 ft. Saturday night, 4,000 ft. Sunday, 5,000 ft. Sunday night, 4,500 ft. Monday, 4,000 ft. Monday night, then 3,500 ft. Tuesday.
• highs 44-40 lows near 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 and Lane County news on-line at eugenedailynews.com.

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