Here is my weekly weather quiz question. What is “Instability“?

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A very strong Jet Stream flow www.wunderground.com/maps/wind/jet-stream  from the northeast will be sending much cooler air to the Pacific Northwest. A weak frontal system moved in today but a stronger cold front www.wpc.ncep.noaa.gov will push through the Pacific Northwest from the northeast Saturday bringing colder air with it.

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Air Quality Index:

Eugene/Springfield: The Air Quality Index is 11 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 23 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 5 in the Good category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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ADVISORIES:

• NONE AT THIS TIME.

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

• Mostly cloudy with a (40%) chance of showers tonight (under 0.10 in. of rain possible),
• Mostly cloudy with a good (50%) chance of AM showers, a bit cooler with showers likely (70%) Saturday afternoon and evening (under 0.10 in. of rain possible),  just partly cloudy late Saturday night,
• Sunny and a bit cooler Sunday, clear at night,
• Mostly sunny and a bit warmer Monday, then partly cloudy Monday night.
• low 37-19 warming to 23 Monday night highs 44-37 warming to 38 Monday.
• A mix of clouds  and sun and a bit warmer Tuesday, more clouds and becoming mostly cloudy with a slight (20%) chance of rain and snow late Tuesday night (snow level 1,000 ft.),
• Mostly cloudy with a slight (20%) chance of rain and a bit warmer Wednesday (snow level 500 ft.) and at night,
• Cloudy with a (40%) chance of rain and a bit warmer Thursday, then mostly cloudy with a (40%) chance of rain Thursday night and Friday.
• highs 43-48 lows 27-34. (seasonal averages high 49 low 35)

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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 (LRAPA)

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Forecast for the Umpqua Valley including Roseburg:

• Mostly cloudy with a slight (20%) chance of rain late tonight (snow level 2,500 ft.),
• Mostly cloudy and a bit cooler with a (30%) chance of rain Saturday, a (30%) chance of rain and snow Saturday night (under 0.10 in. of rain possible, snow level 2,000 ft. falling to 100 ft. late at night),
• Sunny and a bit cooler Sunday, clear Sunday night,
• Sunny and a bit warmer Monday, mostly clear in the evening, then mostly cloudy late Monday night.
• lows 36-19 warming to 25 Monday night highs 46-39 warming to 43 Monday.
• Partly cloudy and a bit warmer Tuesday and Tuesday night,
• Mostly cloudy with a slight (20%) chance of AM rain and snow showers, a bit warmer with a slight (20%) chance of showers Wednesday afternoon, a slight (20%) chance of rain and snow at night,
• Mostly cloudy with a slight (20%) chance of AM rain and snow, a (30%) chance of rain Thursday afternoon, a (40%) chance of rain Thursday night,
• Then mostly cloudy with a (40%) chance of rain Friday.
• highs 48-52 lows 30-36. (seasonal averages high 51 low 37)

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

• Mostly cloudy with a slight (20%) chance of rain late tonight (under 0.10 in. of rain possible),
• Mostly cloudy with a slight (20%) chance of AM coastal rain with coastal rain likely (70%) Saturday afternoon while a (30%) chance of inland rain Saturday (under 0.10 in. of rain possible), a (40%) chance of coastal rain at night while a good (50%) chance of inland evening rain and a good (50%) chance of inland rain and snow late Saturday night (0.10 in. of rain possible),,
• Sunny and a bit cooler Sunday, clear Sunday night,
• Sunny and a bit warmer Monday, mostly clear in the evening, then mostly cloudy Monday night.
• lows 39-23 warming to 28 Monday night highs 49-43 warming to 46 Monday.
• Mostly cloudy and a bit warmer Tuesday, a slight (20%) chance of showers late Tuesday night,
• Mostly cloudy with a slight (20%) chance of showers and a bit warmer Wednesday, mostly cloudy with a slight (20%) chance of rain at night,
• Mostly cloudy with a (30%) chance of rain and a bit warmer Thursday, a good (50%) chance of rain Thursday night,
• Then mostly cloudy and a bit cooler with a (40%) chance of rain Friday.
• highs 52-54 cooling back to 52 Friday lows 32-38. (seasonal averages high 54 low 41)

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Forecast for the Cascades in Lane County:

• Mostly cloudy with a good (50%) chance of showers tonight (under 0.10 in. of rain possible, 1 in. of snow possible),
• Mostly cloudy with showers and a bit cooler Saturday (2 in. of snow possible), evening snow showers, a slight (20%) chance of snow showers and colder late Saturday night,
• Mostly sunny and cooler Sunday, mostly clear at night,
• Sunny and warmer Monday, then partly cloudy Monday night.
• snow level 3,000 ft. tonight, 2,500 ft. Saturday, at the surface Saturday night, free air freezing level at the surface Sunday and Monday, then 2,500 ft. Monday night,
• lows 24-4 warming to 14 Monday night highs 29-18 warming to 30 Monday.
• A mix of clouds and sun and a bit warmer Tuesday, partly cloudy Tuesday night,
• A mix of clouds and sun and a bit warmer Wednesday,becoming mostly cloudy late at night,
• Mostly cloudy with a (30%) chance of rain or snow and a bit cooler Thursday, a (40%) chance of rain or snow Thursday night,
• Then mostly cloudy with a (40%) chance of rain or snow Friday.
• free air freezing level 4,000 ft. Tuesday, 5,500 ft. Tuesday night, 7,000 ft. Wednesday, 7,000 ft. rising to 8,000 ft. Wednesday night, snow level 4,000 ft. Thursday, 3,500 ft. Thursday night, then 2,500 ft. Friday.
• highs 36-42 cooling to 38 Friday lows 20-25.

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