Here is my weekly weather quiz question for the last time. What are “Backing Winds?” Here is the correct answer. Backing Winds are winds which shift in a counterclockwise direction with time at a given location (e.g. from southerly to southeasterly), or change direction in a counterclockwise sense with height (e.g. westerly at the surface but becoming more southerly aloft). The opposite of veering winds. 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) is still dominating our weather picture.  The very slow cooling began Friday with some onshore airflow, but we start to warm back up pretty quickly by Sunday. The graphics for days 1-3 show a backdoor front attempting to move from the northeast to southwest into Oregon.

Note: Eugene set a new record high for Wednesday with 102 and the same for Thursday, Roseburg set a new record of 108 Wednesday and again Thursday, and North Bend set a record high Wednesday of 85 but no record Thursday.  We’ve lost the triple digit highs, but you should still take proper precautions to keep hydrated and cool.

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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 62 in the Moderate category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 52 in the Moderate category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

 

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Advisories:

• A FIRE WEATHER WATCH IS IN EFFECT FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING FOR ABUNDANT LIGHTNING ON DRY FUELS FOR THE KLAMATH BASIN, AND THE FREMONT-WINEMA NATIONAL FOREST.
• AN AIR  QUALITY ALERT IS IN EFFECT UNTIL 7 PM TUESDAY FOR BENTON COUNTY, CLACKAMAS COUNTY, CLATSOP COUNTY, COLUMBIA COUNTY, HOOD RIVER COUNTY, LANE COUNTY, LINCOLN COUNTY, LINN COUNTY, MARION COUNTY, MULTNOMAH COUNTY, POLK COUNTY, TILLAMOOK COUNTY, WASHINGTON COUNTY, YAMHILL COUNTY,  CLARK COUNTY, DESCHUTTES COUNTY AND JEFFERSON COUNTY.
• The Oregon Health Authority issued a Health Advisory for Coffenbury Lake, located at Fort Stevens State Park about five miles northwest of US-101 ALT, Northwest Ridgefield Road near Warrenton in Clatsop County. Water monitoring has confirmed the presence of blue-green algae that can produce toxins in Coffenbury Lake. These blue-green algae levels are likely to be associated with dangerous cyanotoxin concentrations in the water that can be harmful to humans and animals.  People should always avoid areas with visible scum that looks foamy, scummy, thick like paint, pea-green, blue-green or brownish-red. Swimming and high-speed water activities such as water skiing or power boating where ingestion and inhalation exposure can occur are discouraged. Swallowing or inhaling water droplets as a result of these water activities in areas where a bloom has been identified or an advisory issued, can expose people to the toxins that can be produced. Although toxins are not absorbed through the skin, people with skin sensitivities who come into contact with a bloom may experience a puffy, red rash at the affected area. Drinking water directly from Coffenbury Lake at this time is especially dangerous. OHA Public Health Division officials advise campers and other recreational visitors that toxins cannot be removed by boiling, filtering or treating water with camping-style filters.
• The Health Advisory for Odel Lake, located 75 miles southeast of Eugene off highway 58  in the northwest corner of Klamath County HAS BEEN LIFTED. Water monitoring has confirmed that the level of blue-green algae toxins are below guideline values for human exposure. However, Oregon Health officials advise recreational visitors to always be alert to signs of algae blooms in all Oregon waters, because blooms can develop and disappear throughout the season. Only a fraction of the many lakes and waterways in Oregon are monitored for blue-green algae by state, federal and local agencies, therefore, you are your own best advocate when it comes to keeping you and your family safe.
• 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 still hot with smokey haze decreasing but a bit cooler this afternoon, mostly clear tonight,
• Mostly sunny and a bit warmer, Hot again, with patchy smoke Sunday, mostly clear with patchy smoke at night,
• AM clouds, mostly sunny Monday afternoon, then partly cloudy with patchy smoke Monday night.
• highs 88-94 lows 55-60.
• Partly cloudy and a bit cooler Tuesday through Wednesday AM, mostly sunny and a bit cooler in the afternoon, mostly clear Wednesday night,
• Then mostly sunny and a bit cooler Thursday and Friday, mostly clear Thursday night.
• highs 93-89 lows near 58. (seasonal averages high 84 low 52)

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Eugene-Springfield Pollen Count

Grass………. Low (3)
Trees………. Low (3)
Last Counted: 8/2/17
Data Courtesy of Oregon Allergy Associates.
Note: It would seem the pollen season is over.

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Forecast for Roseburg:

• Sunny and a bit cooler, still hot, with patchy smoke this afternoon, partly cloudy this evening, mostly clear late tonight with patchy smoke,
• Sunny and a bit warmer with patchy smoke Sunday, partly cloudy with a slight (20%) chance of isolated evening thunderstorms, mostly clear with patchy smoke at night,
• Partly cloudy with patchy AM smoke, then a slight (20%) chance of thunderstorms Monday afternoon and at night.
• highs near 95 lows near 62.
• Partly cloudy with a slight (20%) chance of thunderstorms Tuesday through Thursday night,
• Then sunny and a bit cooler Friday.
• highs 96-93 lows 64-62. (seasonal averages high 86 low 57)

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

• Sunny this afternoon with patchy inland smoke, partly cloudy with patchy coastal fog late while patchy inland smoke tonight,
• Mostly cloudy in the AM, mostly sunny Sunday afternoon with patchy inland smoke, partly cloudy in the evening mostly cloudy with patchy coastal fog late at night while patchy inland smoke Sunday night,
• Mostly cloudy with patchy AM fog, partly cloudy Monday afternoon, then a slight (20%) chance of thunderstorms at night.
• highs near 66 lows near 55.
• Partly cloudy with a slight (20%) chance of thunderstorms Tuesday and Tuesday night,
• Partly cloudy with a slight (20%) chance of thunderstorms Wednesday and at night,
• Then just partly cloudy Thursday through Friday.
• highs near 65 lows near 55. (seasonal averages high 65 low 53)

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Forecast for the Cascades in Lane County:

• Partly cloudy and a bit cooler with patchy smoke this afternoon, partly cloudy tonight,
• Mostly sunny in the AM, partly cloudy and a bit cooler with patchy smoke Sunday afternoon and at night,
• Partly cloudy and a bit cooler with a slight (20%) chance of showers and thunderstorms Monday afternoon and Monday night, patchy evening smoke.
• free air freezing level above 12,000 ft. today through Sunday, snow level above 8,000 ft. Sunday night through Monday night.
• highs 80-82 lows 53-55.
• Partly cloudy with a slight (20%) chance of showers and thunderstorms and a bit cooler Tuesday  and in the evening, just partly cloudy late Tuesday night,
• Partly cloudy with a slight (20%) chance of showers and thunderstorms Wednesday afternoon and evening, partly cloudy late at night,
• Partly cloudy Thursday with a slight (20%) chance of afternoon and evening showers and thunderstorms, partly cloudy Thursday night,
• Then partly cloudy with a slight (20%) chance of afternoon showers and thunderstorms Friday.
• snow level above 8,000 ft. Tuesday in the evening, free air freezing level above 12,000 ft. late Tuesday night and Wednesday AM, snow level above 8,000 ft. Wednesday afternoon and evening, free air freezing level late Wednesday night and Thursday AM, snow level above 8,000 ft. Thursday afternoon and evening, free air freezing level 12,000 ft. late Thursday night and Friday AM, then snow level above 8,000 ft. Friday afternoon.
• highs near 80 lows near 53.

 

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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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