Here is my weekly weather quiz question for the last time. What is “ Attenuation?” Here is the correct answer. Attenuation refers to the reduction of the radar beam power due to the reflection or absorption of energy when it strikes a target. The greatest attenuation occurs when the radar beam goes through very heavy rain. 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 High Pressure Ridge (Shaded “Arch” shape with blue arrows) took over warming us up. The graphics for days 1-3 shows the surface front that’s moving toward the Pacific Northwest for Sunday. The graphics for days 3-7 show another front that will push into our area by the end of the week.

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Air Quality Index:

Eugene-Springfield: The Air Quality Index is 12 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 10 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 1 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:

• Increasing clouds with a (30%) chance of rain through late evening, mostly cloudy with rain late tonight (0.10 in. of rain possible),
• Mostly cloudy with a good (50%) chance of AM showers, partly cloudy and a bit cooler with a slight (20%) chance of showers Sunday afternoon (under 0.10 in. of rain possible),  just partly cloudy and colder at night,
• Mostly cloudy Monday with a (30%) chance of showers Monday afternoon (under 0.10 in. of rain possible), a (40%) chance of showers and a bit warmer Monday night (under 0.10 in. of rain possible),
• Partly cloudy with a slight (20%) chance of AM showers, a mix of clouds and sun a bit warmer Tuesday afternoon, then just partly cloudy and a bit warmer Tuesday night.
• lows 47-39 warming to 47 Tuesday night highs 60-67.
• Partly cloudy and a bit warmer Wednesday, mostly clear Wednesday night,
• Partly cloudy and a bit cooler Thursday, partly cloudy with a slight (20%) chance of showers at night,
• A mix of clouds and sun with a slight (20%) chance of showers and colder Friday, then partly cloudy with a slight (20%)  chance of showers Friday night and Saturday.
• highs 78-60 lows 49-42. (seasonal averages high 64 low 41)

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Eugene-Springfield Pollen Count:

Grass………. Moderate (5)

Trees………. High (110)

Last Counted: 4/26/17

Data Courtesy of Oregon Allergy Associates.

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Forecast for Roseburg:

• Mostly cloudy with rain likely (70%) late tonight (under 0.10 in. of rain possible),
• Mostly cloudy with a (40%) chance of AM showers (under 0.10 in. of rain possible), just partly cloudy and a bit cooler Sunday afternoon and evening, mostly cloudy at night,
• Mostly cloudy and a bit warmer with a slight (20%) chance of showers Monday afternoon (under 0.10 in. of rain possible) and Monday night (under 0.10 in. of rain possible),
• Mostly cloudy and a bit warmer with a slight (20%) chance of showers Tuesday AM, just mostly cloudy in the afternoon and evening, partly cloudy at night.
• lows 46-42 warming to 53 Tuesday night highs 62-73.
• Sunny and a bit warmer Wednesday, clear Wednesday night,
• Sunny Thursday AM, partly cloudy and a bit cooler partly cloudy with a slight (20%) chance of showers Thursday afternoon, mostly cloudy with a slight (20%) chance of showers and colder at night,
• Mostly cloudy with a slight (20%) chance of showers and a bit cooler Friday, then just partly cloudy Friday night and Saturday.
• highs 82-63 lows 53-42. (seasonal averages high 66 low 44)

 

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

• Mostly cloudy with coastal rain late tonight while inland rain likely (60%) late tonight (0.10 in. of rain possible),
• Mostly cloudy with a (40%) chance of AM showers, just partly cloudy and a bit cooler Sunday afternoon and evening (under 0.10 in. of rain possible), mostly cloudy Sunday night,
• Mostly cloudy and a bit warmer with a (30%) chance of showers Monday afternoon (under 0.10 in. of rain possible) and at night (under 0.10 in. of rain possible),
• Mostly cloudy with a slight (20%) chance of AM showers, just mostly cloudy and a bit warmer Tuesday and Tuesday night.
• lows 48-43 warming to 52 Tuesday night highs 55-62.
• Sunny and a bit warmer Wednesday, mostly clear at night,
• Partly cloudy and a bit cooler Thursday, mostly cloudy and a bit cooler Thursday night and Friday, then partly cloudy Friday night and Saturday.
• highs 65-57 lows 50-46. (seasonal averages high 57 low 45)

 

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Forecast for the Cascades in Lane County:

• Mostly cloudy with a slight (20%) chance of evening rain, rain late tonight (0.25 in. of rain possible),
• AM showers, partly cloudy and a bit cooler with a good (50%) chance of showers Sunday afternoon, (0.10 in. of rain possible), just partly cloudy Sunday night,
• Mostly cloudy Monday and a bit warmer with a (30%) chance of showers in the afternoon, a good (50%) chance of showers at night,
• A slight (20%) chance of AM showers, a mix of clouds and sun and a bit warmer Tuesday afternoon, just partly cloudy Tuesday night.
• snow level 7,500 ft. tonight, 6,500 ft. falling to 5,500 ft. Sunday afternoon, free air freezing level 6,500 ft. Sunday night, snow level 7,500 ft. Monday, 8,000 ft. Monday night, above 8,000 ft. Tuesday, free air freezing level 11,000 ft. Tuesday night.
• lows 35-28 warming to 36 Tuesday night highs 46-57.
• Mostly sunny and a bit warmer Wednesday, mostly clear at night,
• Partly cloudy and a bit cooler with a slight (20%) chance of showers Thursday, a (40%) chance of showers Thursday night,
• A mix of clouds and sun with a (30%) chance of showers and colder Friday, then partly cloudy with a slight (20%) chance of showers Friday night and Saturday (a bit warmer).
• free air freezing level 12,000 ft. Wednesday, 13,000 ft. Wednesday night, snow level above 8,000 ft.  Thursday and Thursday night, 6,500 ft. Friday, 6,000 ft. Friday night, then 6,500 ft. Saturday.
• highs 68-46 lows 42-32.

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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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