Here is my new weekly weather quiz question. What is  “orographic lifting?” Please remember to post your answer as a comment by clicking on “no comments /comments” in the upper right hand portion of this page under the caption, then add your comment. The first person to post the correct answer will win a week of free personalized weather forecasts tailored to your needs. The answer has to be a comment to win. An email answer will not count. Good luck.

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An upper level low (“Shaded “U” shape with blue arrows) is moving through the Pacific giving us showers and cool temperatures.  Short-lived high pressure (Shaded “Arch” shape with blue arrows on previous graphic) will move in for Wednesday, then low pressure returns the chance of rain by nightfall. A frontal system will approach the coast by Saturday increasing our rain chance even more.

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Air Quality Index:

Eugene-Springfield: The Air Quality Index is 43 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 29 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 62 in the Moderate 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 1 AM UNTIL 9 AM WEDNESDAY FOR CENTRAL DOUGLAS COUNTY, EASTERN CURRY COUNTY, JOSEPHINE COUNTY, AND JACKSON COUNTY.
• A HEALTH ADVISORY CONTINUES FOR THE CLACKAMAS COVE PORTION OF THE CLACKAMAS  RIVER IN CLACKAMAS COUNTY. WATER MONITORING BY THE USGS HAS CONFIRMED THE PRESENCE OF BLUE-GREEN ALGAE TOXINS WHICH CAN BE HARMFUL TO HUMANS AND ANIMALS. SWALLOWING, INHALING OR SKIN CONTACT WITH WATER DROPLETS SHOULD BE AVOIDED.
• A HEALTH ADVISORY CONTINUES FOR SUNSET BAY STATE PARK BEACH LOCATED IN COOS COUNTY FOR HIGHER-THAN-NORMAL FECAL BACTERIA WHICH CAN RESULT IN DIARRHEA, STOMACH CRAMPS, SKIN RASHES, UPPER RESPIRATORY INFECTIONS AND OTHER ILLNESSES. DIRECT CONTACT WITH THE WATER – ESPECIALLY BY CHILDREN AND THE ELDERLY, WHO MAY BE VULNERABLE TO WATERBORNE BACTERIA – SHOULD BE AVOIDED IN THIS AREA UNTIL THE ADVISORY IS LIFTED. VISITORS SHOULD AVOID WADING IN NEARBY CREEKS, POOLS OF WATER ON THE BEACH, OR IN DISCOLORED WATER AND STAY CLEAR OF WATER RUNOFF FLOWING INTO THE OCEAN.

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

• Mostly cloudy with a slight (20%) chance of showers this evening, mostly cloudy with patchy fog late tonight,
• Cloudy with areas of AM fog, a mix of clouds and sun and a bit cooler Wednesday afternoon, becoming mostly cloudy with a (40%) chance of rain developing late at night (under 0.10 in. of rain possible),
• Cloudy with AM rain likely (60%), a slight (20%) chance of afternoon showers (under 0.10 in. of rain possible), just mostly cloudy Thursday night and Friday, then mostly cloudy with a slight (20%) chance of rain Friday night.
• lows 35-44 highs 54-59.
• Mostly cloudy and a bit cooler with rain likely (60%) Saturday, cloudy with a (40%) chance of showers at night,
• A mix of clouds and sun and a bit cooler with a good (50%) chance of rain Sunday, a good (50%) chance of showers Sunday night,
• A mix of clouds and sun with a good (50%) chance of showers Monday, mostly cloudy with a (40%) chance of showers at night,
• Then mostly cloudy with a slight (20%) chance of showers Tuesday.
• highs 58-53 warming to 55 Tuesday lows 46-40. (seasonal averages high 56 low 39)

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Your Saturday College Football Forecast:

Preliminary forecasts:

Ducks vs California at Autzen Stadium– Kickoff 7:30 PM PST: Mostly cloudy with a rain likely (60%) early then chance dropping to a 40% chance of showers by the end of the game, 54 cooling slowly as the game progresses.

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Beavers vs UCLA at Riser Stadium- Kickoff 1:30 PM PST: Mostly cloudy with rain likely (60%), 52 warming to 58 as the game progresses, then cooling.

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Forecast for Roseburg:

• Mostly cloudy and a bit cooler with patchy fog and a good (50%) chance of showers tonight with areas of frost late (under 0.10 in. of rain possible),
• Mostly cloudy with patchy AM fog and possible early AM frost Wednesday, partly cloudy in the afternoon, mostly cloudy with a slight (20%) chance of rain Wednesday night and patchy fog late (under 0.10 in. of rain possible),
• Mostly cloudy with a patchy fog and a (30%) chance of rain Thursday AM (under 0.10 in. of rain possible), just mostly cloudy Thursday night,
• Then partly cloudy and a bit warmer Friday and Friday night.
• lows 37-44 highs 56-62.
• Mostly cloudy and warmer with a (30%) chance of showers Saturday, cloudy with a (40%) chance of showers Saturday night,
• A (40%) chance of rain Sunday, evening rain likely (60%), showers likely (60%) at night,
• Cloudy with a good (50%) chance of showers Monday, mostly cloudy with a (30%) chance of showers Monday night,
• Then mostly cloudy with a slight (20%) chance of showers Tuesday.
• highs 62-54 lows 48-38. (seasonal averages high 58 low 42)

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Forecast for the South Oregon Coast including Coos Bay and North Bend:

• Mostly cloudy with a (30%) chance of evening coastal showers while a (30%) chance of inland showers tonight (under 0.10 in. of rain possible), patchy fog tonight and Wednesday AM, just mostly cloudy in the afternoon, partly cloudy with a (40%) chance of evening coastal rain and rain likely (60%) late at night while a slight (20%) chance of inland rain Wednesday night (under 0.10 in. of rain possible),
• Rain likely (70%) Thursday AM, a slight (20%) chance of showers in the afternoon (under 0.10 in. of rain possible), just mostly cloudy at night,
• Then partly cloudy and a bit warmer Friday and Friday night.
• lows 44-48 highs 58-62.
• Mostly cloudy and a bit cooler with a good (50%) chance of showers Saturday, cloudy with a good (50%) chance of showers at night,
• Mostly cloudy with a good (50%) chance of rain Sunday, rain likely (70%) in the evening, showers likely (70%) late Sunday night,
• Mostly cloudy with a good (50%) chance of showers Monday and Monday night,
• Then mostly cloudy with a slight (20%) chance of showers Tuesday.
• highs 62-53 lows 50-44. (seasonal averages high 57 low 44).

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Forecast for the Cascades in Lane County:

• Mostly cloudy and cooler with a (40%) chance of rain and snow showers this evening, a slight (20%) chance of rain and snow showers late tonight (under 0.10 in. of rain possible),
• A mix of clouds and sun and warmer Wednesday, partly cloudy in the evening, mostly cloudy with a slight (20%) chance of rain and snow late at night,
• Mostly cloudy and a bit cooler with rain and snow likely (60%) Thursday AM, a slight (20%) chance of rain and snow showers in the afternoon, partly cloudy with a slight (20%) chance of evening rain and snow  showers, partly cloudy late Thursday night,
• A mix of clouds and sun and warmer Friday, then mostly cloudy Friday night.
• snow level 4,000 ft. tonight, free air freezing level 4,500 ft Wednesday, snow level 4,000 ft. Wednesday night, 4,500 ft. Thursday, 5,000 ft. Thursday night, free air freezing level 7,500 ft. Friday, then 9,000 ft. Friday night.
• lows 24-33 highs 42-39 warming to 48 Friday.
• Mostly cloudy with a (40%) chance of rain Saturday, cloudy with a good (50%) chance of showers at night,
• Mostly cloudy and cooler with a good (50%) chance of rain and snow Sunday, rain and snow showers likely (70%) Sunday night,
• Mostly cloudy and a bit cooler with a good (50%) chance of rain and snow showers Monday, cloudy with a good (50%) chance of rain and snow showers Monday night,
• Then mostly cloudy with a slight (20%) chance of rain and snow showers Tuesday.
• snow level 7,500 ft. Saturday, 5,000 ft. Saturday night and Sunday, 4,500 ft. Sunday night, then 3,500 ft. Monday throughTuesday.
• highs 47-40 lows 35-23.

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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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