Here is my weekly weather quiz question for the last time. What is a “Severe Thunderstorm?” Here is the correct answer. A Severe Thunderstorm is a thunderstorm that produces a tornado, winds of at least 58 mph (50knots), and/or hail at least 1 inch in diameter. Structural wind damage may imply the occurrence of a severe thunderstorm. A thunderstorm wind equal to or greater than 40 mph (35 knots) and/or hail of at least 1 inch is defined as approaching severe.  I’ll have a new weekly weather question for you starting Monday. 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.

________________

An upper level trough of low pressure (Shaded “U” shape with blue arrows) is moving away as upper air high pressure (Shaded “Arch” shape with blue arrows) clears us up and drying us out.  A frontal system finally moved through to bring the change. So far, Sunday looks dry. Low pressure cuts the sunshine short next week. By next Friday a frontal system will be pushing toward the Pacific Northwest.

________________

Air Quality Index:

Eugene-Springfield: The Air Quality Index is 36 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 4 in the Good category measuring Ozone.

Cottage Grove: The Air Quality Index is 34 in the Good category measuring Ozone.

Data courtesy of Lane Regional Air Protection Agency (LRAPA).

________________

Advisories: None At This Time.

________________

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

• Partly cloudy with patchy fog this AM, mostly sunny and a bit warmer this afternoon, partly cloudy tonight,
• Mostly cloudy with a slight (20%) chance of AM showers, a good (50%) chance of showers and a bit cooler Monday afternoon, a slight (20%) chance of evening showers,  a good (50%) chance of showers late Monday night through Tuesday evening, then partly cloudy with a good (50%) chance of showers late Tuesday night.
• highs 76-63 lows 48-44.
• A mix of clouds and sun with a (30%) chance of AM showers, a slight (20%) chance of showers and a bit warmer Wednesday afternoon, mostly cloudy with a slight (20%) chance of showers at night and Thursday AM, a (40%) chance of showers and a bit cooler Thursday afternoon and evening, showers likely (70%) late at night,
• Mostly cloudy with showers likely (70%) Friday AM, a good (50%) chance of showers and a bit warmer Friday afternoon, a (30%) chance of evening showers, then partly cloudy with a slight (20%) chance of showers late Friday night and Saturday.
• highs 68-65  warming back to 68 Saturday lows near 47. (seasonal averages high 72 low 47).

_____

Eugene-Springfield Pollen Count:

Grass………. Moderate (19)

Trees………. Low (11)

Last Counted: 6/10/16

Data Courtesy of Oregon Allergy Associates.

___________________

Forecast for Roseburg:

• Sunny and a bit warmer today, mostly clear this evening, partly cloudy late tonight,
• Partly cloudy with a slight (20%) chance  of AM showers, mostly cloudy and a bit cooler with a slight (20%) chance of showers Monday afternoon, a (30%) chance of showers Monday night,
•  Mostly cloudy and a bit cooler with a (40%) chance of showers Tuesday and at night.
• highs 80-65 lows 50-45.
• Mostly cloudy and a bit warmer with a (30%) chance of showers Wednesday through Thursday, mostly cloudy with showers likely (70%) and a bit warmer Thursday night and Friday, then mostly cloudy with (30%) chance of showers Friday night and Saturday.
• highs 67-74 lows 47-50. (seasonal averages high 75 low 51).

________________

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

• Sunny and a bit cooler today, mostly clear this evening, mostly cloudy late tonight,
• Mostly cloudy with a (30%) chance of showers and a bit cooler Monday and Monday night,
• Mostly cloudy and a bit cooler with a good (50%) chance of showers Tuesday and at night.
• highs 62-59 lows 52-48.
• Mostly cloudy with a (30%) chance of showers Wednesday through Thursday, showers likely (70%) Thursday night and Friday (a bit warmer), then mostly cloudy with a (30%) chance of showers Friday night and Saturday.
• highs 60-63 lows 50-52. (seasonal averages high 61 low 50)

________________

Forecast for the Cascades in Lane County:

• Mostly sunny and a bit warmer today, partly cloudy tonight,
• A mix of clouds and sun with a (30%) chance of showers and a bit cooler Monday afternoon, mostly cloudy with a good (50%) chance of evening showers, a good (50%) chance of rain and snow showers late at night,
• Mostly cloudy with a good (50%) chance of rain and snow showers and a bit cooler Tuesday afternoon and evening, mostly cloudy with a good (50%) chance of rain and snow showers in the evening, then partly cloudy with a good (50%) chance of rain and snow showers late Tuesday night.
• free air freezing level 11,000 ft. today and tonight, snow level 8,000 ft. Monday, 7,500 ft. falling to 5,500 ft. late Monday night, 4,500 ft. Tuesday, then 5,500 ft. Tuesday night.
• highs 66-48 lows 38-35.
• A mix of clouds and sun with a (40%) chance of rain and snow showers and a bit warmer Wednesday, partly cloudy with a (40%) chance of evening rain and snow showers, mostly cloudy with a (40%) chance of showers Wednesday night,
• Mostly cloudy with a good (50%) chance of showers and a bit cooler Thursday through Friday, a (30%) chance of evening showers, partly cloudy with a slight (20%) chance of showers Friday night and Saturday AM, then mostly sunny and a bit warmer with a slight (20%) chance of showers Saturday afternoon.
• snow level 5,500 ft. Wednesday, 6,500 ft. Wednesday night, 6,000 ft. Thursday, 6,500 ft. Thursday night, 6,000 ft. Friday, then 7,000 ft. Friday night and Saturday.
• highs 53-47 warming to 57 Saturday lows near 35.

________________

**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.

________________

Get your local Eugene-Springfield and Lane County news on-line at eugenedailynews.com.

________________