Here is my weekly weather quiz question for the last time. What is “Accretion?” Here is the correct answer. Accretion is the growth of a precipitation particle by the collision of a frozen particle with a supercooled liquid water droplet which freezes upon impact. I’ll have a new weekly weather quiz question for you starting Monday. Please remember to post your answer at the bottom of this page. An email will not suffice. The first person to post the correct answer will win a week of free personalized weather forecasts tailored to your needs.  Good luck.

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The Upper level airflow will keep the moisture pouring into the Pacific Northwest. The days 1-3 graphic shows a stationary front that slowly gets pushed southward toward us.. The graphic for days 3-7 shows that frontal system, commonly called a “backdoor” front because it moves in from the opposite direction from which fronts usually come toward us, through the Pacific Northwest to bring in colder air late this coming week. We’re still seeing snow accumulations increasing in the mountains. For mountain snow conditions at the local ski areas check out their websites or give them a call.

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Air Quality Index:

Eugene-Springfield: The Air Quality Index is 8 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 18 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 15 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: YELLOW- Caution is Advised.

*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:

• A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 5 AM MONDAY FOR THE NORTHERN OREGON CASCADES AND THE CASCADES IN LANE COUNTY.
• A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 4 AM WEDNESDAY FOR THE EASTERN DOUGLAS COUNTY FOOTHILLS, AND THE SOUTH CENTRAL OREGON CASCADES.
• 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.
• A Blue-Green Algae Health Advisory remains in effect for Agency Lake. Agency Lake is located just north of Upper Klamath Lake near Klamath Falls along Highway 97 in Klamath County. Water monitoring on the lake has confirmed the presence of high levels of blue-green algae and associated toxins that can be harmful to people and animals. Swallowing water while swimming or inhaling water droplets as a result of high-speed water activities, such as water skiing and power boating, should be avoided in areas where blooms are identified. Although toxins are not absorbed through the skin, contact with cells from a bloom can cause skin irritation and a red, puffy rash in individuals with skin sensitivities, or those who develop rashes easily.

 

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

• Mostly cloudy with showers tonight (0.25 in. of rain possible),
• Cloudy and a bit cooler with a good (50%) chance of AM showers a slight (20%) chance of showers Monday afternoon (under 0.10 in. of rain possible), partly cloudy with patchy fog late Monday night and Tuesday AM, just partly cloudy and a bit cooler in the afternoon, partly cloudy with areas of frost late Tuesday night,
• A mix of clouds and sun with areas of AM frost and patchy freezing fog, increasing clouds to cloudy with a (40%) chance of rain and snow and a bit cooler Wednesday afternoon, then mostly cloudy with a good (50%) chance of rain and snow Wednesday night.
• lows 38-27 warming to 29 Wednesday night highs 44-35.
• Mostly cloudy and a bit warmer with a slight (20%) chance of rain and snow Thursday, a good (50%) chance of rain and snow (snow level 1,000 ft.) Thursday  night,
• Mostly cloudy with a good (50%) chance of rain and snow showers Friday, a slight (20%) chance of rain and snow showers at night,
• A mix of clouds and sun and a bit cooler Saturday with a slight (20%) chance of rain and snow showers, partly cloudy with a slight (20%) chance of rain Saturday night,
• Then cloudy and a bit warmer with a slight (20%) chance of rain Sunday.
• highs near 38 lows 30-20. (seasonal averages high 46 low 34)

 

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Forecast for Roseburg:

• Mostly cloudy with showers likely (70%) this evening, a good (50%) chance of showers late tonight (0.25 in. of rain possible),
• Mostly cloudy and a bit cooler Monday with a (40%) chance of showers (under 0.10 in. of rain possible, snow level 2,500 ft.), mostly cloudy in the evening, partly cloudy with patchy fog late at night,
• Areas of AM fog, partly cloudy and a bit cooler Tuesday and in the evening, mostly cloudy with patchy fog late Tuesday night,
• Mostly cloudy with patchy AM fog and a slight (20%) chance of rain and snow, a good (50%) chance of rain and a bit cooler Wednesday afternoon, then rain likely (70%) Wednesday night.
• lows 39-33 warming to 39 Wednesday night highs 46-42 warming to 44 Wednesday.
• Mostly cloudy with a (40%) chance of rain Thursday AM, a good (50%) chance of showers and a bit warmer in the afternoon, cloudy with rain and snow showers late at night,
• Mostly cloudy with a (40%) chance of AM rain and snow showers, rain and snow showers likely (70%) and a bit cooler Friday afternoon, a (30%) chance of rain and snow showers Friday night,
• Then mostly cloudy and a bit cooler with a slight (20%) chance of rain and snow showers Saturday through Sunday.
• highs 45-40 warming to 42 Sunday lows 34-27. (seasonal averages high 48 low 36)

 

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

• Mostly cloudy with coastal showers tonight while evening inland showers likely (70%) and a good (50%) chance of inland showers late tonight (0.25 in. of rain possible),
• Mostly cloudy with AM coastal showers likely (70%) and partly cloudy Monday afternoon while a (40%) chance of inland AM showers and partly cloudy and a bit cooler inland in the afternoon (under 0.10 in. of rain possible), partly cloudy with patchy fog late Monday night,
• Mostly cloudy with areas of AM fog, partly cloudy and a bit cooler Tuesday afternoon and evening, mostly cloudy with patchy fog late Tuesday night,
• Patchy AM fog, mostly cloudy and a bit cooler with a (30%) chance of rain Wednesday, then mostly cloudy with a good (50%) chance of rain Wednesday night.
• lows 42-36 warming to 38 Wednesday night highs 52-48.
• Mostly cloudy with a (30%) chance of AM rain with a (30%) chance of showers Thursday afternoon, a evening showers likely (70%), rain and snow showers likely (70%) late Thursday night,
• A (30%) chance of rain and snow showers Friday AM, a (40%) chance of showers and a bit cooler in the afternoon, a slight (20%) chance of evening showers, a slight (20%) chance of rain and snow showers late Friday night,
• Then mostly cloudy and a bit cooler with a slight (20%) chance of showers Saturday through Sunday (a bit warmer).
• highs 48-45 warming back to 48 Sunday lows 37-33. (seasonal averages high 51 low 40)

 

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Forecast for the Cascades in Lane County:

• Cloudy with snow showers tonight (3-7 in. of snow possible),
• Mostly cloudy with snow showers likely (70%) Monday AM (1 in. of snow possible), a mix of clouds and sun in the afternoon, partly cloudy in the evening, mostly cloudy late Monday night,
• A mix of clouds and sun and a bit cooler Tuesday, partly cloudy with a slight (20%) chance of evening snow showers, mostly cloudy and cold late Tuesday night,
• Cloudy with a slight (20%) chance of snow Wednesday AM, a bit cooler with a good (50%) chance of snow in the afternoon, then mostly cloudy with a slight (20%) chance of snow Wednesday night.
• snow level 2,500 ft. tonight and Monday, free air freezing level at the surface Monday night, at the surface rising to 3,500 ft. Tuesday afternoon, snow level 3,500 ft. Tuesday night, then at the surface Wednesday and Wednesday night.
• lows 26-22 highs 30-26.
• Mostly cloudy and a bit warmer with a (40%) chance of snow Thursday, a good (50%) chance of snow at night,
• Mostly cloudy and a bit cooler with snow showers likely (70%) Friday, a good (50%) chance of snow showers Friday night,
• A mix of clouds and sun with a slight (20%) chance of snow showers and a bit cooler Saturday, partly cloudy with a slight (20%) chance of snow at night,
• Then a mix of clouds and sun and a bit warmer with a slight (20%) chance of snow Sunday.
• snow level 2,500 ft. Thursday, then at the surface Thursday night through Sunday.
• highs 32-22 lows 18-12.

 

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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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