Here is my weekly weather quiz question for the last time. What is a “Hodograph“?  Here is the correct answer.  A Hodograph is a polar coordinate graph which shows the vertical wind profile of the lowest 7000 meters of the atmosphere. These plots are used to determine the advection patterns aloft, whether a thunderstorm will rotate, and the type of thunderstorms that you will likely see that day. I’ll have a new weekly weather quiz for you starting Monday.  The first person to post the correct answer as a comment on this page will win a week of free personalized weather forecasts tailored to your needs. Good luck.

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An Upper Level High Pressure Ridge (Shaded “Arch” shape with arrows) is still controlling our weather with northwest airflow, but about midweek an Upper Level Low Pressure Trough  (Shaded “U” shape with arrows on same graphic) will take over returning the wet weather pattern. The graphics for days 1-3 show a frontal system just offshore Tuesday. The graphics for days 3-7  show a frontal system  that pushes through  the Pacific Northwest Wednesday and another that will push through Oregon Thursday night into Friday. Yet another frontal system will be offshore by next Sunday.

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Air Quality Index:

Eugene/Springfield: The Air Quality Index is 58 in the Moderate category measuring Particulate Matter.

Oakridge: The Air Quality Index is 28 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 58 in the Moderate category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

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Advisories:

• AN AIR STAGNATION ADVISORY IS IN EFFECT UNTIL 1 PM WEDNESDAY FOR THE EASTERN COLUMBIA RIVER GORGE, THE LOWER COLUMBIA BASIN OF OREGON, THE FOOTHILLS OF THE NORTHERN BLUE MOUNTAINS, THE FOOTHILLS OF THE SOUTHERN BLUE MOUNTAINS, NORTH CENTRAL OREGON, AND CENTRAL OREGON.
• AN AIR STAGNATION ADVISORY IS IN EFFECT UNTIL 4 AM WEDNESDAY FOR THE SOUTH CENTRAL OREGON COAST, CENTRAL DOUGLAS COUNTY, EASTERN CURRY COUNTY, JOSEPHINE COUNTY, THE EASTERN DOUGLAS COUNTY FOOTHILLS, JACKSON COUNTY, THE SOUTH CENTRAL OREGON CASCADES, THE SOUTHERN OREGON CASCADES, THE SISKIYOU MOUNTAINS, THE KLAMATH BASIN, NORTHERN AND EASTERN KLAMATH COUNTY, THEN WESTERN, CENTRAL AND EASTERN LAKE COUNTY.

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

• Clear with patchy fog and freezing fog late tonight and Monday AM, sunny in the afternoon, mostly clear Monday night,
• Mostly sunny Tuesday AM, partly cloudy and a bit warmer in the afternoon and evening, becoming mostly cloudy late Tuesday night,
• Mostly cloudy and a bit cooler with rain and a bit cooler Wednesday, then rain likely (70%) Wednesday night.
• low 30-39 highs 54-57 cooling to 52 Wednesday.
• Mostly cloudy with rain and breezy Thursday (Thanksgiving Day), showers at night,
• Showers and a bit cooler Friday, rain likely (70%) Friday night,
• Mostly cloudy with a good (50%) chance of rain Saturday, a (40%) chance of showers at night,
• Then a (30%) chance of showers and a bit warmer Sunday.
• highs 52-49 warming  back to 52 Sunday lows 42-38. (seasonal averages high 51 low 37)

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Home Wood Heating Advisory:

Posted Daily

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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Your College Football Forecast    

Friday November 23rd: The Civil War Game

Ducks vs Beavers at Reser Stadium – Kickoff: 1:00 PM- PST – Too early for a preliminary weather forecast, but it looks like showers will be likely.

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Forecast for Roseburg:

• Hazy this evening, clear late tonight,
• Patchy AM fog, sunny and warmer Monday afternoon, mostly clear and hazy late at night,
• AM haze and sun, partly cloudy and hazy Tuesday afternoon and evening, becoming mostly cloudy late Tuesday night,
• Mostly cloudy and a bit cooler with rain Wednesday and at night.
• lows 43-40 warming back to 43 Tuesday night and Wednesday night highs 60-56.
• Mostly cloudy with rain and a bit cooler Thursday (Thanksgiving Day) and Thursday night,
• Rain and a bit cooler Friday and at night,
• Mostly cloudy with rain likely (70%) Saturday, then mostly cloudy with a (30%) chance of rain Saturday night and Sunday (a bit warmer).
• highs near 52 lows 44-40. (seasonal averages high 52 low 40)

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

• Partly cloudy with coastal haze and mostly cloudy with coastal haze late tonight while clear with inland haze tonight,
• AM coastal clouds and partly cloudy and warmer Monday afternoon while partly cloudy in the AM inland and sunny inland and warmer Monday afternoon, mostly clear and hazy late Monday night,
• Mostly cloudy and a bit warmer at the shore Tuesday while AM inland sun and haze and partly cloudy and a bit warmer inland in the afternoon, mostly cloudy with a (40%) chance of coastal rain at night while partly cloudy in the evening inland and mostly cloudy with a slight (20%) chance of inland rain late at night (under 0.10 in. of rain possible),
• Then mostly cloudy with rain and a bit cooler Wednesday and Wednesday night.
• lows 43-47 highs 59-62 cooling back to 59 Wednesday night.
• Mostly cloudy with rain and a bit cooler Thursday (Thanksgiving Day) and Thursday night,
• Mostly cloudy with rain Friday and at night,
• Rain likely (70%) Saturday and Saturday night,
• Then mostly cloudy and as bit warmer with a (30%) chance of rain Sunday.
• highs 57-55 lows near 50. (seasonal averages high 54 low 42)

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Forecast for the Cascades in Lane County:

• Clear tonight,
• Sunny Monday, mostly clear Monday night,
• Mostly sunny Tuesday, partly cloudy in the evening, mostly cloudy late at night,
• Mostly cloudy with AM rain, then rain and snow and cooler Wednesday afternoon and Wednesday night.
• free air freezing level 12,000 ft. tonight, 11,000 ft. Monday, 10,000 ft. late Monday night and Tuesday, 9,000 ft. Tuesday night, then snow level 5,500 ft. Wednesday and Wednesday night.
• lows 32-34 highs 52-40.
• Rain and snow and a bit cooler Thursday (Thanksgiving Day), rain and snow showers at night,
• Mostly cloudy with rain and snow showers and a bit cooler Friday, rain and snow Friday night,
• Mostly cloudy with a good (50%) chance of rain and snow Saturday, then mostly cloudy with a (40%) chance of rain and snow showers and a bit warmer Saturday night and Sunday.
• snow level 4,500 ft. Thursday through Friday, 4,000 ft. Friday night, 3,500 ft. Saturday, 5,500 ft. Saturday night, then 5,000 ft. Sunday.
• highs 40-34 warming to 35 Saturday lows near 30.

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