Here is my new weekly weather quiz question. What is “Rayleigh Scattering?” 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 low (Shaded “U” shape with blue arrows) that was controlling our weather is being replaced by high pressure (Shaded “Arch” shape with blue arrows) and that means the rain is gone, for now.

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Air Quality Index:

Eugene-Springfield: The Air Quality Index is 38 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 20 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 30 in the Good category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA).

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Advisories:

• A HEALTH ADVISORY CONTINUES FOR SUNSET BAY STATE PARK BEACH LOCATED IN COOS COUNTY FOR HIGHER-THAN-NORMAL FECAL BACTERIA WHICH CAN RESULT IN DIARRHEA, STOMACH CRAMPS, SKIN RASHES, UPPER RESPIRATORY INFECTIONS AND OTHER ILLNESSES. DIRECT CONTACT WITH THE WATER – ESPECIALLY BY CHILDREN AND THE ELDERLY, WHO MAY BE VULNERABLE TO WATERBORNE BACTERIA – SHOULD BE AVOIDED IN THIS AREA UNTIL THE ADVISORY IS LIFTED. VISITORS SHOULD AVOID WADING IN NEARBY CREEKS, POOLS OF WATER ON THE BEACH, OR IN DISCOLORED WATER AND STAY CLEAR OF WATER RUNOFF FLOWING INTO THE OCEAN.
• A HEALTH ADVISORY CONTINUES FOR UPPER KLAMATH LAKE AND AGENCY LAKE DOWN TO KENO DAM, LOCATED JUST NORTH OF KLAMATH FALLS ALONG HIGHWAY 97 IN KLAMATH COUNTY. WATER MONITORING BY THE USGS HAS CONFIRMED THE PRESENCE OF BLUE-GREEN ALGAE TOXINS WHICH CAN BE HARMFUL TO HUMANS AND ANIMALS. SWALLOWING, INHALING OR SKIN CONTACT WITH WATER DROPLETS SHOULD BE AVOIDED.

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Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis:

• Mostly sunny and warmer today, Wednesday and Thursday, mostly clear each night.
• highs 84-86 lows 49-53.
• Sunny and warmer Friday and Saturday, clear Friday night, partly cloudy Saturday night,
• Mostly sunny, but cooler Sunday and Monday, mostly clear at night.
• highs 90-83 lows near 54. (seasonal averages high 79 low 49)

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Forecast for the Umpqua Basin including Roseburg:

• Sunny and a bit warmer today, mostly clear tonight,
• Partly cloudy Wednesday AM, sunny in the afternoon, clear Wednesday night,
• Sunny and warmer Thursday, clear at night.
• highs 89-94 lows near 55.
• Sunny and warmer Friday, clear Friday night,
• Then mostly sunny and cooler Saturday, Sunday and Monday, mostly clear each night.
• highs 102-89 lows 60-54. (seasonal averages high 81 low 53)

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Forecast for the South Oregon Coast including Coos Bay and North Bend:

• Sunny and a bit cooler today, partly cloudy this evening, mostly cloudy late  tonight and Wednesday AM, sunny and a bit cooler in the afternoon, mostly clear Wednesday night,
• Sunny Thursday, then mostly clear at  night.
• highs 72-67 warming to 70 lows 56-53.
• Mostly sunny and a bit warmer Friday, mostly clear at night,
• Sunny Saturday, partly cloudy late Saturday night and Sunday, mostly clear at night,
• Then mostly sunny Monday.
• highs 73-67 lows 56-53. (seasonal averages high 66 low 51).

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Forecast for the Cascades in Lane County:

• Mostly sunny and warmer today, Wednesday and Thursday, clear each night.
• free air freezing level 14,000 ft. today and tonight, 15,000 ft. Wednesday through Thursday, then 16,000 ft. Thursday night.
• highs 73-78 lows 40-46.
• Sunny Friday and Saturday, clear both nights,
• Mostly sunny and a bit cooler Sunday and Monday, mostly clear at night.
• free air freezing level 16,000 ft. Friday and Friday night, 15,000 ft. Saturday and Saturday night, 14,000 ft. Sunday, then 16,000 ft. Sunday night and Monday.
• highs 82-72 lows 53-48.

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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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