Here is my weekly weather quiz question for the last time. What is the “Lifted Index? Here is the correct answer.  Lifted Index(abbrev. LI)- A common measure of atmospheric instability. Its value is obtained by computing the temperature that air near the ground would have if it were lifted to some higher level (around 18,000 feet, usually) and comparing that temperature to the actual temperature at that level. Negative values indicate instability – the more negative, the more unstable the air is, and the stronger the updrafts are likely to be with any developing thunderstorms. However there are no “magic numbers” or threshold LI values below which severe weather becomes imminent.

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An Upper Level Low  and surface low with it associated cold front are approaching the California coast keeping the weaker flow of coastal moisture still aimed our way. The graphics for days 1-3  show the frontal system, as described above ,apparently falling as part as it makes landfall. The graphics for days 3-7  Tuesday through next Saturday show a quiet weather pattern, but a frontal system can be seen offshore to our west Saturday.

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Air Quality Index:

Eugene/Springfield: The Air Quality Index is 32 in the Good category measuring Ozone.

Oakridge: The Air Quality Index is 6 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 31 in the Good category measuring Ozone.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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ADVISORIES:

• A FLOOD WARNING IS IN EFFECT UNTIL LATE NEXT WEDNESDAY EVENING FOR THE JOHN DAY RIVER AT SERVICE CREEK AFFECTING WHEELER COUNTY DUE TO RAIN AND SNOW MELT.
• A FLOOD ADVISORY IS IN EFFECT UNTIL TUESDAY AFTERNOON FOR THE SPRAGUE RIVER NEAR BEATY AFFECTING KLAMATH COUNTY DUE TO RAIN AND SNOW MELT.
• A FLOOD WARNING IS IN EFFECT FOR THE SILVIES RIVER NEAR BURNS AFFECTING HARNEY  COUNTY UNTIL LATE NEXT WEDNESDAY EVENING DUE TO RAIN AND SNOW MELT.
• A FLOOD ADVISORY IS IN EFFECT FOR BAKER COUNTY UNTIL 5 PM MDT SUNDAY DUE TO RAIN AND SNOW MELT.

HEALTH ADVISORIES:

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

• Partly cloudy with a slight (20%) chance of evening showers, just partly cloudy late tonight (under 0.10 in. of rain possible),
• A mix of clouds and sun and slightly cooler with a slight (20%) chance of showers Sunday afternoon, mostly cloudy with a slight (20%) chance of evening showers, a good (50%) chance of showers late Sunday night (0.25 in. of rain possible),
• Mostly cloudy with showers likely (70%) and a bit cooler Monday (0.25 in. of rain possible), a good (50%) chance of evening showers, a slight (20%) chance of showers late at night (under 0.10 in. of rain possible),
• A mix of clouds and sun and a bit warmer with a slight (20%) chance of showers Tuesday, then mostly clear Tuesday night.
• lows 42-44 cooling back to 42 Tuesday night highs 62-56 warming to 65 Tuesday.
• Mostly sunny and a bit warmer Wednesday, partly cloudy Wednesday night,
• Partly cloudy and a bit warmer Thursday, partly cloudy at night,
• Mostly sunny and a bit warmer Friday and Saturday, mostly clear Friday night.
• highs 72-83 lows 45-52. (seasonal averages high 67 low 43)

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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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Eugene-Springfield Pollen Count:

Forecast for the Umpqua Valley including Roseburg:

• Mostly cloudy with a slight (20%) chance of evening thunderstorms, partly cloudy with a slight (20%) chance of showers tonight (0.10 in. of rain possible),
• Mostly cloudy with a slight (20%) chance of showers and a bit warmer Sunday afternoon, cloudy with a good (50%) chance of evening showers, showers late Sunday night (0.50 in. of rain possible),
• AM showers likely (70%), a bit cooler with showers likely (70%) and a slight (20%) chance of thunderstorms Monday afternoon (0.25 in. of rain possible), a (30%) chance of showers at night (under 0.10 in. of rain possible),
• Partly cloudy and warmer with a slight (20%) chance of showers Tuesday afternoon, mostly clear Tuesday night.
• lows 42-45 cooling to 43 Monday night warming to 45 Tuesday night highs 62-57 warming to 67 Tuesday.
• Mostly sunny and a bit warmer Wednesday, partly cloudy Wednesday night,
• Mostly sunny and a bit warmer Thursday, mostly clear at night,
• Sunny and a bit warmer Friday, clear Friday night,
• Then sunny and a bit warmer Saturday.
• highs 72-87 lows 47-54. (seasonal averages high 69 low 46)

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

• Mostly cloudy with a slight (20%) chance of coastal showers, becoming partly cloudy late tonight (under 0.10 in. of rain possible),
• Mostly cloudy with a slight (20%) chance of showers and slightly warmer Sunday, evening showers likely (70%), showers late Sunday night (0.25 in. of rain possible),
• Mostly cloudy with a good (50%) of coastal showers while inland AM showers likely (70%) and a good (50%) chance of inland showers Monday afternoon (0.10 in. of rain possible), a slight (20%) chance of showers at night,
• Partly cloudy and warmer Tuesday, then mostly clear Tuesday night,
• lows 42-46 cooling to 43 Tuesday night highs 58-62.
• Mostly sunny and a bit warmer Wednesday, partly cloudy Wednesday night,
• Mostly sunny and a bit warmer Thursday, mostly clear at night,
• Then sunny and a bit warmer Friday and Saturday, clear Friday night.
• highs 62-73 lows 43-48. (seasonal averages high 59 low 47)

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

• Mostly cloudy with evening showers and snow showers with a slight (20%) chance of thunderstorms, a good (50%) chance of rain and snow showers late tonight (0.25 in. of rain possible, 1 in. of snow possible),
• A mix of clouds and sun with a slight (20%) chance of AM rain and snow showers, a good (50%) chance of showers and a bit cooler Sunday afternoon (0.10 in. of rain possible, little or no snow accumulation expected), a good (50%) chance of evening showers, rain and snow likely (70%) late Sunday night (under 0.10 in. of rain possible),
• Mostly cloudy and a bit cooler with rain and snow showers Monday (snow possibly heavy in the afternoon), evening rain and snow showers likely (70%), then a slight (20%) chance of rain and snow showers  late at night,
• Clouds and sun with slight (20%)chance of AM rain and snow showers, a (40%) chance of showers and a bit warmer Tuesday afternoon, partly cloudy with a slight (20%) chance of evening showers, then just partly cloudy late Tuesday night.
• snow level 4,500 ft. tonight, 4,000 ft. rising to 5,500 ft. Sunday afternoon, 5,500 ft. Sunday night, then 4,500 ft. Monday and Monday night, 5,000 ft. Tuesday, then 5,500 ft. Tuesday night.
• lows 29-32 cooling back to 29 Monday night and Tuesday night highs 45-42 warming to 47 Tuesday.
• Mostly sunny and a bit warmer with a slight (20%) chance of showers Wednesday afternoon, partly cloudy Wednesday night,
• Some AM clouds, sunny and a bit warmer Thursday afternoon, mostly clear Thursday night,
• Partly cloudy and a bit warmer Friday, partly cloudy Friday night,
• Then mostly sunny and a bit warmer Saturday.
• snow level  6,000 ft. Wednesday, free air freezing level 9,000 ft Wednesday night and Thursday, 10,000 ft. Thursday night, 12,000 ft. Friday, then 13,000 ft. Saturday.
• highs 55-70 lows 34-42.