Here is my weekly weather quiz question. What is  a “Back Building Thunderstorm?” 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.

________________

The Jet Stream (Shaded area with blue arrows shown west to east into Oregon) hangs on to rain chances over the Pacific Northwest keeping us in the moist westerly airflow. The graphics for days 1-3 show a new frontal system approaching the Oregon coast Thursday night into Friday. The graphics for days 3-7 show the frontal system that moved in as a cold front sliding back to the north as a warm front Saturday and the next front that slips through between Tuesday and Wednesday of next week.

________________

 

Air Quality Index:

Eugene-Springfield: The Air Quality Index is 13 in the Good category measuring Particulate Matter.

Oakridge: The Air Quality Index is 19 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 4 in the Good category measuring Particulate Matter.

Data courtesy of Lane Regional Air Protection Agency (LRAPA)

__________________

Advisories:

• A Health Advisory has been issued  for South Tenmile Lake, located 10 miles north of North Bend in Coos County. Visual inspection indicates a blue-green algae bloom is present in the Coleman Arm of South Tenmile Lake, and Oregon Department of Environmental Quality is collecting and analyzing samples to confirm whether or not associated toxins are also present. If present, these toxins can be harmful to humans and animals. People should avoid swallowing water while swimming or inhaling water droplets as a result of high-speed water activities, such as water skiing or power boating, in areas where blooms are identified. Although toxins are not absorbed through the skin, people who have skin sensitivities may experience a puffy red rash at the affected area. Drinking water directly from South Tenmile Lake at this time is especially dangerous. Oregon public health officials advise campers and other recreational visitors that toxins cannot be removed by boiling, filtering or treating water with camping-style filters.
• A Health Advisory has been issued  for the water around Eagle Ridge County Park on Upper Klamath Lake. The park is located off Highway 140, 15 miles west of Klamath Falls in Klamath County. Water monitoring has confirmed the presence of blue-green algae and the toxins they produce in this area of Upper Klamath Lake. These toxin concentrations can be harmful to humans and animals.
• A Health Advisory has been issued for Detroit Lake, located 46 miles SE of Salem in Marion County. Water monitoring has confirmed the presence of blue-green algae and the toxins they produce in Detroit Lake. These toxin concentrations can be harmful to humans and animals. People should avoid swallowing water while swimming or inhaling water droplets as a result of high-speed water activities, such as water skiing or power boating, in areas where blooms are identified. Although toxins are not absorbed through the skin, people who have skin sensitivities may experience a puffy, red rash at the affected area.
• A Permanent Health Advisory remains in effect for the South Umpqua River and Lawson Bar. Pools in the bedrock along the rivers edge are known to develop Blue-green Algae (cyanobacterial) blooms that can be harmful to pets and people if accidental ingestion occurs. Signs have been posted along several access areas along the river.

________________

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

• Mostly cloudy with rain and a bit cooler this afternoon (0.25 in. of rain possible) and breezy (Wind: S 5-10 mph increasing to S 15-25 mph afternoon gusts to 35 mph), rain tonight (0.25 in. of rain possible),
• Cloudy and a bit cooler with rain Friday (0.50 in. of rain possible), a good (50%) chance of evening rain, just mostly cloudy late Friday night,
• A mix of clouds and sun and a bit warmer Saturday, then mostly clear at night.
• highs 66-64 warming to 76 Saturday lows 56-50.
• Mostly sunny and a bit warmer Sunday, clear at night,
• Sunny Monday, partly cloudy Monday night and Tuesday AM, mostly sunny in the afternoon, mostly clear Tuesday night,
• Then mostly sunny Wednesday.
• highs 83-80 lows 54-50. (seasonal averages high 73 low 48)

_____

 

Eugene-Springfield Pollen Count:

Grass………. High (41)

Trees………. Moderate (16)

Last Counted: 6/15/17

Data Courtesy of Oregon Allergy Associates.

_________________

 

Forecast for Roseburg:

• Cloudy  with rain this afternoon and evening (under 0.10 in. of rain possible), a good (50%) chance of rain late tonight (under 0.10 in. of rain possible),
• Cloudy with a (30%) chance of showers  Friday (under 0.10 in. of rain possible), mostly cloudy with a (30%) chance of showers at night,
• Mostly cloudy Saturday AM, sunny and a bit warmer in the afternoon, then clear Saturday night.
• highs 70-82 lows 59-54.
• Sunny and a bit warmer Sunday and Monday, mostly clear at night,
• Mostly sunny and a bit warmer Tuesday, clear Tuesday night,
• Then sunny and a bit warmer Wednesday.
• highs 88-84 lows 56-59 cooling back to 56 Tuesday night. (seasonal averages high 76 low 52)

 

_____________________

 

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

• Mostly cloudy with rain this afternoon and evening (0.25 in. of rain possible), a good (50%) chance of showers late tonight (0.25 in. of rain possible),
• Cloudy with coastal showers likely (70%) while a good (50%) chance of inland showers Friday (0.10 in. of rain possible), mostly cloudy with a (30%) chance of evening showers, just mostly cloudy late Friday night and Saturday AM, sunny and a bit warmer in the afternoon, then clear Saturday night,
• highs 62-64 lows 57-54.
• Sunny and a bit warmer Sunday, mostly clear at night,
• Mostly sunny and a bit cooler Monday, mostly clear in the evening, partly cloudy late Monday night,
• Partly cloudy Tuesday AM, then sunny in the afternoon and Wednesday, clear Tuesday night.Tuesday night.
• highs near 70 lows 55-57 cooling back to 55 . (seasonal averages high 62 low 51)

 

________________

 

Forecast for the Cascades in Lane County:

• Mostly cloudy with rain and a bit cooler this afternoon  (0.25 in. of rain possible), showers likely (70%) late tonight,
• Mostly cloudy and a bit cooler with rain Friday and Friday night,
• Partly cloudy and a bit warmer Saturday, then mostly clear at night.
• snow level above 8,000 ft. today through Friday night, free air freezing level 13,000 ft.rising to 14,000 ft. Saturday, then 15,000 ft. rising to 16,000 ft. Saturday night.
• highs 58-54 warming to 67 Saturday lows 46-42 warming to 44 Saturday night.
• Mostly sunny and a bit warmer Sunday, clear Sunday night,
• Sunny and a bit warmer Monday, mostly clear at night,
• Then mostly sunny and a bit warmer Tuesday and Wednesday, mostly clear Tuesday night.
• free air freezing level 16,000 ft. Sunday through Wednesday.
• highs 74-76 cooling to 72 Tuesday and Wednesday lows 49-46.

 

________________

**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.

_______________