Here is my weekly weather quiz question. What is a “Baroclinic leaf shield?” 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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Southwest airflow from the Jet Stream (Shaded “Arch” shape with blue arrows aimed Southwest to Northeast) will keep warm air headed our way. The graphics for days 1-3 show a weak frontal system moving through Oregon late tonight. The graphics for days 3-7 show the frontal system that attempt to move into the Pacific Northwest Monday.

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Air Quality Index:

Eugene-Springfield: The Air Quality Index is 17 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 14 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 15 in the Good category measuring Ozone.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

 

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Advisories:

•  The Oregon Health Authority has updated the health advisory issued June 30 for Lake Billy Chinook, located about 12 miles west of Madras in Jefferson County. The update lifts the advisory on those areas of the Deschutes and Crooked River of Lake Billy Chinook arms affected by the advisory, and confines the advisory on the Metolius Arm to Perry South Cove. Water monitoring has confirmed that the level of blue-green algae toxins are below guideline values for human exposure. However, OHA recommends that people remain cautious when using the lake, particularly with pets because toxins are still well above the very low exposure levels established for dogs.
• A 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 and a bit cooler today, clear this evening, partly cloudy late tonight and Thursday, mostly clear Thursday night,
• Mostly sunny and a bit warmer Friday, then mostly clear at night.
• highs 80-83 lows 55-52.
• Mostly sunny and a bit warmer Saturday and Sunday, mostly clear both nights,
• Mostly sunny and a bit cooler Monday, clear Monday night,
• Then sunny and a bit cooler Tuesday.
• highs 86-83 lows 56-52. (seasonal averages high 84 low 52)

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Eugene-Springfield Pollen Count

Grass………. Moderate (16)

Trees………. Low (3)

Last Counted: 7/19/17

Data Courtesy of Oregon Allergy Associates.

Note: It would seem the pollen season just about over.

 

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Forecast for Roseburg:

• Partly cloudy this AM, sunny and a bit cooler this afternoon, clear in the evening, mostly cloudy with patchy fog late tonight and Thursday AM, a slight (20%) chance of AM showers, partly cloudy and a bit cooler Thursday afternoon and evening, mostly clear Thursday night,
• Mostly sunny and a bit warmer Friday, then mostly clear at night.
• highs 83-80 warming to 86 Friday lows near 55.
• Mostly sunny and a bit warmer Saturday, mostly lear at night,
• Sunny Sunday, clear Sunday night,
• Sunny and a bit cooler Monday and Tuesday, clear at night.
• highs 90-86 lows near 58. (seasonal averages high 85 low 57)

 

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

• Mostly cloudy this AM, sunny this afternoon, mostly cloudy with patchy drizzle late tonight and patchy inland fog late at night,
• Mostly cloudy with patchy AM drizzle, partly cloudy Thursday afternoon mostly clear in the evening, partly cloudy late Thursday night,
• Then mostly sunny Friday and mostly clear at night.
• highs near 63 lows near 54.
• Mostly sunny Saturday and Sunday, mostly clear both nights,
• Sunny Monday, mostly clear at night,
• Then mostly sunny Tuesday.
• highs 65-63 warming to 65 Tuesday lows near 54. (seasonal averages high 65 low 53)

 

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Forecast for the Cascades in Lane County:

• Sunny and a bit cooler today, partly cloudy tonight and Thursday AM, mostly sunny and a bit cooler in the afternoon, clear Thursday night,
• Mostly sunny and a bit warmer Friday, then clear at night.
• free air freezing level above 12,000 ft. today, above 12,000 ft falling to 12,000 ft. late tonight, then above 12,000 ft. Thursday through Friday night,
• highs 72-67 warming to 73 Friday lows near 45.
• Mostly sunny and a bit warmer Saturday and Sunday, mostly clear both nights,
• Then sunny and a bit cooler Monday and Tuesday, clear Monday night.
• free air freezing level above 12,000 ft. Saturday through Tuesday,
• highs 78-75 lows 48-50 cooling back to 48 Monday night.

 

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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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