Here is my new weekly weather quiz question. What is“Isentropic Analysis?

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An Upper Level High Pressure Ridge (“Arch” shape) offshore will be approaching the Pacific Northwest giving us dry with warmer daytime highs. The graphics for days 1-3 show no frontal activity through the period. The graphics for days 3-7 show an increase in complex frontal systems moving our way Sunday through next Thursday bringing back the rain chances.

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Air Quality Index:

Eugene/Springfield: The Air Quality Index is 18 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 21 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 17 in the Good category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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ADVISORIES:

• A FROST ADVISORY IS IN EFFECT FROM 2 AM UNTIL 10 AM TODAY FOR THE SOUTH CENTRAL OREGON COAST AND THE CURRY COUNTY COAST.

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

• Some AM clouds with areas of frost, a mix of clouds and sun and a bit warmer this afternoon, mostly clear tonight,
• Mostly sunny start, a mix of clouds and sun and a bit warmer Friday, becoming mostly cloudy with a slight (20%) chance of rain at night,
• A mix of clouds and sun and a bit warmer with a slight (20%) chance of rain Saturday, a slight (20%) chance of evening rain, then a good (50%) chance of rain Saturday night.
• highs 57-62 lows 32-42.
• Mostly cloudy and cooler with rain likely (70%) Sunday, a good (50%) chance of rain Sunday night,
• Mostly cloudy with a good (50%) chance of rain Monday and at night,
• Mostly cloudy with a good (50%) chance of AM rain, rain likely (70%) and a bit cooler Tuesday afternoon and evening, a good (50%) chance of rain Tuesday night and Wednesday AM, then rain likely (70%) Wednesday afternoon.
• highs 52-50 lows 39-35. (seasonal averages high 57 low 37)

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Home Wood Heating Advisory:

Posted Daily

Eugene-Springfield: GREEN– Burning is Allowed.

Oakridge: GREEN– Burning is Allowed.

*Note: Pellet stoves may be used anytime if they produce no visible emissions.

Data courtesy of Lane Regional Air Protection Agency (LRAPAz

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Forecast for the Umpqua Valley including Roseburg:

• Sunny and warmer today, clear tonight,
• Partly cloudy start, mostly cloudy and a bit cooler Friday afternoon, a slight (20%) chance of showers with patchy fog late at night,
• Mostly cloudy and a bit warmer with a slight (20%) chance of showers Saturday, then a good (50%) chance of showers late Saturday night.
• highs 60-58 warming back to 60 Saturday lows 34-43.
• Mostly cloudy and a bit cooler with showers likely (70%) Sunday, a good (50%) chance of showers Sunday night,
• Mostly cloudy with a good (50%) chance of AM rain and snow showers, a (40%) chance of showers Monday afternoon, a good (50%) chance of evening showers, rain and snow showers likely (70%) late at night and Tuesday AM, showers and a bit cooler Tuesday afternoon, rain and snow showers likely (70%) Tuesday night,
• Then mostly cloudy and a bit cooler with rain and snow showers likely (70%) Wednesday.
• highs 55-52 lows 42-39. (seasonal averages high 59 low 40)

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

• Areas of AM frost, sunny and a bit warmer this afternoon, clear tonight,
• Mostly cloudy with patchy AM coastal fog and frost while inland areas of AM frost and patchy fog, just mostly cloudy and a bit cooler Friday afternoon, mostly cloudy with a slight (20%) chance of showers Friday night with patchy inland fog late,
• Patchy AM fog, mostly cloudy with a slight (20%) chance of showers and a bit warmer Saturday afternoon, a good (50%) chance of evening showers, then showers likely (70%) late Saturday night.
• highs 58-55 warming to 57 Saturday lows 34-42.
• Mostly cloudy and a bit cooler with showers likely (70%) Sunday, a good (50%) chance of showers Sunday night,
• Mostly cloudy with a good (50%) chance of showers Monday and in the evening, showers likely (70%) Monday night,
• Mostly cloudy with AM showers likely (70%), showers and a bit cooler Tuesday afternoon, then showers likely (70%) Tuesday night and Wednesday.
• highs 52-50 lows 38-36. (seasonal averages high 55 low 42)

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Forecast for the Northern Oregon Cascades including the Cascades in Lane County:

• Mostly sunny and a bit warmer today, mostly clear tonight,
• Mostly sunny start, a mix of clouds and sun and a bit warmer Friday afternoon, partly cloudy with a slight (20%) chance of rain and snow at night,
• Clouds and sun with a slight (20%) chance of AM rain and snow, a slight (20%) chance of rain and a (40%) chance of snow Saturday afternoon, then mostly cloudy with a good (50%) chance of rain and snow Saturday night.
• free air freezing level 4,000 ft. rising to 6,500 ft. falling to 5,500 ft. this afternoon, 6,500 ft. falling to 5,500 ft. late tonight, 5,000 ft. rising to 6,500 ft. Friday afternoon, snow level 4,500 ft. Friday night, 4,000 ft. Saturday, then 4,500 ft. Saturday night.
• highs 40-43 lows 20-28.
• Mostly cloudy and a bit cooler with rain and snow Sunday, evening snow and rain likely (70%), a good (50%) chance of snow and rain late Sunday night and Monday AM, a bit cooler with snow and rain Monday afternoon, evening rain and snow likely (70%), rain likely (70%) with a good (50%) chance of snow late at night,
• Mostly cloudy with snow and rain Tuesday and in the evening, snow likely (70%) late Tuesday night and Wednesday AM, then snow and rain and a bit cooler Wednesday afternoon.
• snow level 4,000 ft. Sunday, 3,500 ft. Sunday night, 3,000 ft. Monday, 3,500 ft. Monday night and Tuesday, then 3,000 ft. Tuesday night and Wednesday.
• highs 38-32 lows 26-22.

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For all of your Eugene-Springfield and Lane County News, Weather, and Sports go to: EugeneDailyNews.com

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