Here is my weekly weather quiz question. What is an “Air Mass Thunderstorm?” Please remember to post your answer at the bottom of this page. 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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An approaching Upper Level High Pressure Ridge (Shaded “Arch” shape with blue arrows) helps push a frontal system toward us as shown on the days 1-3 graphic. The graphic for days 3-7 shows more complex frontal systems heading our way. 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 17 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 35 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 23 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: YELLOW – Caution is Advised.

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:

• AN AIR STAGNATION ADVISORY IS IN EFFECT FROM 10 PM THURSDAY UNTIL 4 AM SUNDAY FOR CENTRAL DOUGLAS COUNTY, EASTERN CURRY COUNTY, JOSEPHINE COUNTY, JACKSON COUNTY, THE KLAMATH BASIN, NORTHERN AND EASTERN KLAMATH COUNTY, AND CENTRAL, EASTERN AND WESTERN LAKE COUNTY.
• 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:

• Cloudy with a good (50%) chance of showers tonight (under 0.10 in. of rain possible),
• Cloudy with a slight (20%) chance of AM showers, a mix of clouds and sun and a bit warmer with a slight (20%) chance of showers Thursday afternoon, partly cloudy in the evening, mostly cloudy with areas of freezing fog late Thursday night,
• Partly cloudy with patchy freezing fog Friday AM, mostly sunny and a bit cooler in the afternoon, partly cloudy in the evening, mostly cloudy with patchy freezing fog late Friday night,
• Cloudy with patchy freezing fog Saturday AM, partly cloudy and a bit cooler  Saturday afternoon and evening, then mostly cloudy with patchy freezing fog late Saturday night.
• lows 33-30 warming to 32 Saturday night highs 50-47.
• Mostly cloudy and a bit warmer with a slight (20%) chance of rain Sunday, mostly cloudy with a slight (20%) chance  of showers Sunday night,
• Mostly cloudy and a bit warmer Monday, partly cloudy at night,
• A mix of clouds and sun and a bit cooler with a slight (20%) chance of rain Tuesday, mostly cloudy with a (40%) chance of rain at night,
• Then cloudy and a bit warmer with a good (50%) chance  of showers Wednesday.
• highs 48-46 warming to 48 Wednesday lows 35-32. (seasonal averages high 49 low 35)

 

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Forecast for Roseburg:

• Cloudy with a good (50%) chance of rain and snow showers tonight (under 0.10 in. of rain possible, snow level 2,500 ft.),
• Mostly cloudy with a slight (20%) chance of AM rain and snow showers (snow level 2,000 ft.), just partly cloudy and a bit warmer Thursday afternoon, partly cloudy with patchy freezing fog late Thursday night and Friday AM, sunny and a bit warmer Friday afternoon, then partly cloudy with patchy freezing fog late at night,
• Partly cloudy with patchy AM freezing fog, partly cloudy and a bit warmer Saturday afternoon, mostly clear in the evening, then patchy freezing fog late Saturday night.
• lows 35-32 warming back to 35 Saturday night highs 49-54.
• Mostly cloudy with patchy fog Sunday AM, partly cloudy and a bit cooler Sunday afternoon, mostly cloudy with a slight (20%) chance of rain Sunday night,
• Just mostly cloudy and cooler Monday, partly cloudy at night,
• Mostly cloudy with a slight (20%) chance of rain and a bit cooler Tuesday, cloudy with a (40%) chance of  rain Tuesday night,
• Then cloudy and a bit warmer with a good (50%) chance of rain Wednesday.
• highs 52-48 warming back to 52 Wednesday lows near 35. (seasonal averages high 51 low 37)

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

• Cloudy with a (30%) chance of evening coastal showers with a (40%) chance of scattered coastal showers late while a (40%) chance of scattered inland showers tonight (under 0.10 in. of rain possible),
• Mostly cloudy with a slight (20%) chance of AM showers, just mostly cloudy Thursday afternoon, partly cloudy with patchy inland freezing fog late Thursday night and Friday AM, sunny and a bit warmer in the afternoon, partly cloudy Friday night with patchy inland freezing fog late at night,
• Patchy AM inland freezing fog, partly cloudy Saturday afternoon, then partly cloudy with patchy inland freezing fog late at night.
• lows near 40 highs 55-55.
• Mostly cloudy with patchy fog and a slight (20%) chance of AM rain, mostly cloudy and a bit warmer Sunday afternoon, mostly cloudy with a slight (20%) chance of rain Sunday night,
• Mostly cloudy and a bit warmer Monday, partly cloudy at night,
• Mostly cloudy with a slight (20%) chance of rain and a bit cooler Tuesday, cloudy with a good (50%) chance of rain at night,
• Then mostly cloudy and a bit warmer with rain likely (70%) Wednesday.
• highs 55-53 warming back to 55 Wednesday lows 40-42 . (seasonal averages high 52 low 40)

 

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Forecast for the Cascades in Lane County:

• Cloudy with snow showers likely (70%) this evening, scattered snow showers likely (70%) late tonight (under 0.10 in. of rain possible),
• Mostly cloudy with a (30%) chance of snow showers Thursday AM, a slight (20%) chance of rain and snow showers in the afternoon (under 0.10 in. of rain possible), partly cloudy and cold Thursday night,
• Partly cloudy Friday AM, mostly sunny and a bit warmer in the afternoon, then partly cloudy Friday night through Saturday night.
• snow level 2,500 ft. tonight and Thursday, free air freezing level 3,500 ft. Thursday night, 5,000 ft. Friday 7,000 ft. Friday night, 8,000 ft. Saturday, then 9,000 ft. Saturday night.
• lows 20-18 warming to 26 Saturday night highs 33-43.
• Partly cloudy Sunday, mostly cloudy at night,
• A mix of clouds and sun Monday, partly cloudy Monday night,
• A mix of clouds and sun with a slight (20%) chance of rain and snow Tuesday, then mostly cloudy with a (40%) chance of rain and snow Tuesday night and Wednesday.
• free air freezing level 9,000 ft. Sunday, 7,000 ft. Sunday night, 7,500 ft. Monday and Monday night, snow level 6,000 ft. Tuesday, then 5,000 ft. Tuesday night and Wednesday.
• highs 43-37 lows 20-26.

 

 

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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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