Here is my weekly weather quiz question. What is  a “Back Door Cold Front?”  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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The graphics for days 1-3 show the frontal system that moved through Oregon. An Upper Level Low Pressure Trough  (Shaded “U” shape with blue arrows) takes over enhancing rain chances for a couple more days. The graphics for days 3-7 show a frontal system falling apart as it approaches the Pacific Northwest.

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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 30 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 3 in the Good category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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Advisories:

• A Health Advisory has been issued  for the water around Eagle Ridge County Park on Upper Klamath Lake. The park is located off Highway 140, 15 miles west of Klamath Falls in Klamath County. Water monitoring has confirmed the presence of blue-green algae and the toxins they produce in this area of Upper Klamath Lake. These toxin concentrations can be harmful to humans and animals.
• A Health Advisory has been issued for Detroit Lake, located 46 miles SE of Salem in Marion County. Water monitoring has confirmed the presence of blue-green algae and the toxins they produce in Detroit Lake. These toxin concentrations can be harmful to humans and animals. People should avoid swallowing water while swimming or inhaling water droplets as a result of high-speed water activities, such as water skiing or power boating, in areas where blooms are identified. Although toxins are not absorbed through the skin, people who have skin sensitivities may experience a puffy, red rash at the affected area.
• 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 cloudy with sun breaks and showers with a slight (20%) chance of thunderstorms and a bit cooler this afternoon (0.25 in. of rain possible, more in storms), showers likely (70%) with a slight (20%) chance of thunderstorms this evening, showers late tonight (0.25 in. of rain possible, more in storms) and Saturday AM, showers likely (70%) with a slight (20%) chance of thunderstorms and a bit warmer in the afternoon (0.25 in. of rain possible) and evening, showers likely (70%) late Saturday night (0.10 in. of rain possible),
• Mostly cloudy with a slight (20%) chance of showers and a bit warmer Sunday, then a (40%) chance of showers at night.
• highs 60-66 lows 47-45 warming back to 47 Sunday night.
• Mostly cloudy with a (30%) chance of showers and a bit cooler Monday and in the evening, a slight (20%) chance of rain or drizzle late Monday night and Tuesday AM, a mix of clouds and sun and a bit warmer Tuesday with a slight (20%) chance of afternoon showers, partly cloudy with a slight (20%) chance of showers at night,
• Then partly cloudy and a bit warmer Wednesday through Thursday.
• highs 64-72 lows 47-45. (seasonal averages high 71 low 47)

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Eugene-Springfield Pollen Count:

Grass………. High (25)

Trees………. Moderate (18)

Last Counted: 6/9/17

Data Courtesy of Oregon Allergy Associates.

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Forecast for Roseburg:

• Cloudy with showers and isolated thunderstorms this afternoon (0.10 in. of rain possible) and evening, showers likely (70%) late tonight (0.25 in. of rain possible),
• Mostly cloudy with showers and isolated thunderstorms and a bit cooler Saturday afternoon (0.25 in. of rain possible), cloudy with evening showers and thunderstorms, a good (50%) chance of showers late Saturday night (0.25 in. of rain possible),
• Mostly cloudy and a bit warmer with a showers likely (70%) Sunday, then mostly cloudy with a (40%) chance of showers Sunday night.
• highs 62-57 warming to 62 Sunday lows near 48.
• Mostly cloudy with a slight (20%) chance of showers Monday through Tuesday, partly cloudy and a bit warmer Tuesday night and Wednesday, mostly clear Wednesday night,
• Then mostly sunny and a bit warmer Thursday.
• highs 65-75 lows near 45. (seasonal averages high 74 low 51)

 

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

• Mostly cloudy with scattered coastal showers while while scattered showers and isolated thunderstorms   inland this afternoon (0.25 in. of rain possible), coastal showers tonight while scattered inland evening showers and showers late tonight (0.25 in. of rain possible),
• Mostly cloudy with showers and isolated thunderstorms Saturday afternoon (0.50 in. of rain possible), scattered coastal showers at night while a good (50%) chance of scattered inland showers and isolated thunderstorms in the evening, a good (50%) chance of showers late at night (under 0.10 in. of rain possible),
• Mostly cloudy with a good (50%) chance of coastal showers and a bit warmer Sunday while inland showers likely (70%), then a (%) chance of showers Sunday night.
• highs near 58 lows 52-48 warming to 50 Sunday night.
• Mostly cloudy with a (30%) chance of showers Monday, a slight (20%) chance of showers at night,
• Mostly cloudy a bit warmer with a slight (20%) chance of showers Tuesday, just partly cloudy and a bit warmer Tuesday night and Wednesday, mostly clear Wednesday night,
• Then mostly sunny and a bit warmer Thursday.
• highs 60-62 lows 50-48. (seasonal averages high 61 low 50)

 

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Forecast for the Cascades in Lane County:

• Cloudy with rain and snow showers with a slight (20%) chance of thunderstorms and a bit cooler this afternoon (0.25 in. of rain possible) and this evening, rain and snow showers late tonight (0.25 in. of rain possible, 1-3 in. of snow possible),
• AM rain and snow showers, mostly cloudy and a bit cooler with rain and snow showers and a slight (20%) chance of thunderstorms Saturday afternoon and in the evening (0.50 in. of rain possible, 1-3 in. of snow possible), rain and snow showers late at night,
• Mostly cloudy with rain and snow showers likely (70%) and a bit warmer Sunday afternoon, showers likely (70%) Sunday night.
• snow level 5,500 ft. today, 5,000 ft. tonight through Saturday night, 4,500 ft. Sunday, then 6,000 ft. Sunday night.
• highs 50-45 lows 34-32 warming back to 34 Sunday night.
• Mostly cloudy with a good (50%) chance of rain and snow showers Monday AM, a bit warmer with a good (50%) chance of showers in the afternoon, a (40%) chance of showers in the evening, a slight (20%) chance of rain or drizzle late Monday night,
• A slight (20%) chance of rain or drizzle Tuesday AM, a mix of clouds and sun and a bit warmer in the afternoon, just partly cloudy Tuesday night,
• Then partly cloudy and a bit warmer Wednesday through Thursday.
• snow level 5,500 ft. Monday, 6,000 ft. Monday night and Tuesday AM, free air freezing level 9,000 ft. Tuesday afternoon, 9,000 ft. falling to 6,000 ft. late Tuesday night, 6,000 ft. rising to 10,000 ft. Wednesday afternoon, 10,000 ft. falling to 7,500 ft. Wednesday night, then 7,500 ft. rising to 10,000 ft. Thursday afternoon.
• highs 50-65 lows 35-37.

 

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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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