Here is my weekly weather quiz question for the last time. What is a “Theodolite?” Here is the correct answer. A Theodolite is an instrument used in surveying to measure horizontal and vertical angles with a small telescope that can move in the horizontal and vertical planes. It used to track the movements of either a ceiling balloon or a radiosonde. I’ll have a new weekly weather quiz 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. Good luck.

________________

 

An upper level low pressure trough (Shaded “U” shape with blue arrows) is going to take over returning westerly airflow which will cool us off. A surface thermal low pressure trough (Red “L” with dashed line) is moving eastward away from the coast also helping to increase cooler onshore airflow.We’re finally going to get away from record heat. Eugene: Friday 104 and today 100. Roseburg: 107 Friday and 101 today.

________________

Air Quality Index:

Eugene-Springfield: The Air Quality Index is 46 in the Good category measuring Ozone.

Oakridge: The Air Quality Index is 20 in the Good category measuring Particulate Matter.

Cottage Grove: The Air Quality Index is 40 in the Good category measuring Ozone.

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

________________

 

Advisories:

• A RED FLAG WARNING IS IN EFFECT THROUGH 8 PM TONIGHT FOR WIND, LOW RELATIVE HUMIDITY AND INCREASINGLY UNSTABLE CONDITIONS FOR NORTH OREGON COAST RANGE, THE EAST SLOPES OF OF THE OF THE CENTRAL OREGON COAST RANGE, THE NORTH OREGON CASCADE FOOTHILLS, THE CENTRAL OREGON CASCADE FOOTHILLS, THE MT. HOOD NATIONAL FOREST, WEST OF CASCADE CREST AND THE WILLAMETTE NATIONAL FOREST.
• A RED FLAG WARNING IS IN EFFECT FROM  NOON UNTIL 9 PM THIS EVENING FOR  STRONG GUSTY WINDS WITH LOW RELATIVE HUMIDITY FOR THE SOUTH CENTRAL OREGON DESERT INCLUDING THE BLM LAND IN EASTERN LAKE COUNTY AND WESTERN LAKE COUNTY.
• A RED FLAG WARNING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY IS IN EFFECT FROM 1 PM UNTIL 11 PM SUNDAY FOR THE CENTRAL MOUNTAINS OF OREGON, THE EAST SLOPES OF THE NORTHERN OREGON CASCADES AND AND THE LOWER COLUMBIA BASIN OF OREGON.
• A RED FLAG WARNING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY IS IN EFFECT FOR THE KLAMATH BASIN AND THE FREMONT-WINEMA NATIONAL FOREST FROM NOON UNTIL 9 PM SUNDAY.
• A RED FLAG WARNING IS IN EFFECT FROM NOON UNTIL 9 PM SUNDAY EVENING FOR STRONG WINDS AND LOW RELATIVE HUMIDITY AND HIGH FIRE DANGER FOR THE KLAMATH BASIN AND THE FREMONT-WINEMA NATIONAL FOREST.
• AN EXCESSIVE HEAT WARNING IS IN EFFECT  THROUGH 9 PM THIS EVENING FOR THE COAST RANGE OF NORTHWEST OREGON, THE CENTRAL COAST RANCE OF WESTERN OREGON, THE GREATER PORTLAND METRO AREA, THE CENTRAL WILLAMETTE VALLEY, THE SOUTH WILLAMETTE VALLEY,  THE WESTERN COLUMBIA RIVER GORGE, THE NORTH OREGON CASCADE FOOTHILLS, THE CASCADE FOOTHILLS IN LANE COUNTY, AND THE CASCADES IN LANE COUNTY.
• A FIRE WEATHER WATCH IS IN EFFECT FROM SUNDAY AFTERNOON THROUGH THROUGH MONDAY EVENING FOR STRONG GUSTY WINDS AND AND LOW RELATIVE HUMIDITY FOR THE EAST SLOPES OF THE NORTHERN OREGON CASCADES AND THE LOWER COLUMBIA BASIN OF OREGON.
• A HEAT ADVISORY IS IN EFFECT UNTIL 9 PM THIS EVENING FOR THE CENTRAL COLUMBIA RIVER GORGE AND THE UPPER HOOD RIVER VALLEY.
• A HEAT ADVISORY IS IN EFFECT UNTIL 2 AM SUNDAY FOR  CENTRAL DOUGLAS COUNTY, EASTERN CURRY COUNTY, JOSEPHINE COUNTY, THE EASTERN DOUGLAS COUNTY FOOTHILLS AND JACKSON  COUNTY.
• A health advisory has been issued for the Ross Island Lagoon and the mouth of the lagoon as it connects to the Holgate Channel. Ross Island Lagoon is located about one river mile south of downtown Portland in Multnomah County. The advisory is being issued due to visual confirmation of a blue-green algae bloom in the lagoon. Oregon Public Health officials advise people to avoid swallowing or inhaling water droplets as a result of swimming or high-speed water activities, such as water skiing and power boating in areas where blooms are identified.
• A health advisory has been issued for Agency Lake. Agency Lake is located just north of Upper Klamath Lake near Klamath Falls along Highway 97 in Klamath County. Water monitoring on the lake has confirmed the presence of high levels of blue-green algae and associated toxins that can be harmful to people and animals. Swallowing water while swimming or inhaling water droplets as a result of high-speed water activities, such as water skiing and power boating, should be avoided in areas where blooms are identified. Although toxins are not absorbed through the skin, contact with cells from a bloom can cause skin irritation and a red, puffy rash in individuals with skin sensitivities, or those who develop rashes easily.
• A Blue-Green Algae health advisory remains in effect for Howard Bay (sometimes called Howards Bay or Howard’s Bay) in Upper Klamath Lake ONLY. 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.

 

________________

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

• Clear tonight,
• Sunny and cooler but still warm Sunday, mostly clear at night,
• Mostly sunny and a bit cooler Monday, clear Monday night,
• Sunny and just a bit warmer Tuesday, then clear Tuesday night.
• lows 53-50 warming back to 53 Tuesday night highs 88-82 warming to 85 Tuesday.
• Mostly sunny and a bit warmer Wednesday, Thursday and Friday, clear each night,
• Then sunny and a bit cooler Saturday.
• highs 91-96 cooling to 86 Saturday lows near 55. (seasonal averages high 82 low 51)

_____

Eugene-Springfield Pollen Count:

Grass………. Low (3)

Trees………. Low (0)

Last Counted: 8/11/16

Data Courtesy of Oregon Allergy Associates.

The Grass and Tree Pollen season is officially over now.

___________________

Forecast for Roseburg:

• Clear tonight,
• Sunny and a little bit cooler Sunday, mostly clear Sunday night,
• Then sunny and a bit cooler Monday and clear at night,
• Then sunny and a bit warmer Tuesday, clear at night.
• lows 60-55 highs 94-88 warming to 90 Tuesday.
• Then sunny and a bit warmer Wednesday through Saturday (a bit cooler Saturday), clear each night.
• highs 93-101 cooling to 92 Saturday lows 56-59. (seasonal averages high 84 low 55)

 

________________

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

• Clear this evening at the shore and mostly cloudy with patchy fog late while mostly clear inland tonight,
• Mostly cloudy with patchy AM fog at the shore while sunny and a bit warmer inland Sunday afternoon, mostly clear in the evening, mostly cloudy late Sunday night and Monday AM, sunny and a bit warmer in the afternoon, then mostly cloudy late Monday night.
• lows near 52 highs 63-66.
• AM clouds, sunny and a bit warmer Tuesday afternoon, clear at night,
• Then sunny and a bit warmer Wednesday, Thursday, Friday and Saturday (a bit cooler), clear each night.
• highs 65-74 cooling to 65 Saturday lows 52-54. (seasonal averages high 66 low 53)

 

________________

 

Forecast for the Cascades in Lane County:

• Clear tonight,
• Sunny and a bit cooler Sunday, partly cloudy at night,
• Mostly sunny and a bit cooler Monday, clear Monday night,
• Sunny and a bit warmer Tuesday, then clear Tuesday night.
• free air freezing level 16,000 ft.tonight, 15,000 ft. Sunday, then 14,000 ft. Sunday night through Tuesday night.
• lows 54-44 highs 80-73 warming to 75 Tuesday.
• Then sunny and a bit warmer Wednesday, Thursday, Friday and Saturday, clear each night,
• free air freezing level 14,000 ft. Wednesday, 15,000 ft. Wednesday night, then 14,000 ft. Thursday through Saturday.
• highs 80-82 cooling to 79 Tuesday lows 52-54 cooling to 50 Friday night..

________________

**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.

_______________