An Upper Level High Pressure Ridge (“Arch “Shape) keeps us hot for one more day. The graphics for days 1-3 show no frontal systems moving through the Pacific Northwest. The graphics for days 3-7 Friday through Tuesday show a cold front moves through on Thursday into Friday and then another cold front pushes through between Saturday.
ADVISORIES:
- *A RED FLAG WARNING IS IN EFFECT FROM 2 PM UNTIL 8 PM TODAY FOR STRONG GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR THE KLAMATH BASIN AND THE FREMONT-WINEMA.
- *A RED FLAG WARNING IS IN EFFECT FROM NOON TODAY TO 11 PM WEDNESDAY FOR STRONG GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR THE JOHN DAY VALLEY, THE SOUTHERN BLUE MOUNTAINS, THE CENTRAL MOUNTANS OF OREGON, THE WARM SPRINGS RESERVATION, THE NORTHERN DESCHUTES NATIONAL FOREST, AND THE SOUTHERN DESCHUTES NATIONAL FOREST.
- A RED FLAG WARNING IS IN EFFECT FOR STRONG GUSTY WIND AND LOW RELATIVE HUMIDITY FROM 2 PM UNTIL 8 PM TODAY FOR THE WESTERN ROGUE BASIN, THE ILLINOIS VALLEY, AND THE EASTERN ROGUE VALLEY.
- *A FIRE WEATHER WATCH IS IN EFFECT FOR STRONG GUSTY WIND AND LOW RELATIVE HUMIDITY FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY EVENING. FOR THE WESTERN ROGUE BASIN, THE ILLINOIS VALLEY, AND THE EASTERN ROGUE VALLEY.
- A FIRE WEATHER WATCH IS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR STRONG GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR THE KLAMATH BASIN AND THE FREMONT-WINEMA.
- A FIRE WEATHER WATCH IS IN EFFECT FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING FOR STRONG GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR THE CANYON GRASSLANDS OF WALLOWA COUNTY.
- *AN EXTREME HEAT WARNING IS IN EFFECT UNTIL 10 PM TONIGHT FOR TUALATIN VALLEY, PORTLAND WEST HILLS AND CHEHALEM MOUNTAIN, INNER PORTLAND METRO, EAST PORTLAND METRO, OUTER SOUTHEAST PORTLAND METRO, WEST CENTRAL WILLAMETTE VALLEY, EAST CENTRAL WILLAMETTE VALLEY, BENTON COUNTY LOWLANDS, LINN COUNTY LOWLANDS, LANE COUNTY LOWLANDS, WEST COLUMBIA RIVER GORGE I-84 CORRIDOR, UPPER HOOD RIVER VALLEY, AND CENTRAL COLUMBIA RIVER GORGE I-84 CORRIDOR.
- A HEAT ADVISORY IS IN EFFECT UNTIL 2 AM WEDNESDAY FOR CENTRAL DOUGLAS COUNTY.
- A HEAT ADVISORY IS IN EFFECT FROM NOON MDT UNTIL 9 PM MDT TODAY FOR MALLHEUR COUNTY, AND THE OREGON LOWER TREASURE VALLEY.
- AN EXTREME HEAT WARNING IS IN EFFECT UNTIL 2 AM WEDNESDAY FOR EASTERN CURRY COUNTY AND JOSEPHINE COUNTY, AND JACKSON COUNTY.
- *AN EXTREME HEAT WARNING IS IN EFFECT UNTIL 10 PM TONIGHT FOR THE EASTERN COLUMBIA RIVER GORGE OF OREGON, THE LOWER COLUMBIA BASIN OF OREGON, AND THE FOOTHILLS OF THE NORTHERN BLUE MOUNTAINS OF OREGON.
- *AN EXTREME HEAT WARNING IS IN EFFECT UNTIL 10 PM TONIGHT FOR THE JOHN DAY BASIN, THE FOOTHILLS OF THE SOUTHERN BLUE MOUNTAINS OF OREGON, NORTH CENTRAL OREGON, AND CENTRAL OREGON.
- A HEAT ADVISORY IS IN EFFECT UNTIL 11 PM TONIGHT FOR THE NORTH OREGON COAST RANGE LOWLANDS, THE CENTRAL OREGON COAST RANGE HIGHLANDS, AND THE LOWER COLUMBIA RIVER.
HEALTH ADVISORIES:
- A PERMANENT HEALTH ADVISORY REMAINS IN EFFECT FOR THE SOUTH UMPQUA RIVER 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.
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Air Quality Index:
Eugene/Springfield: The Air Quality Index is 40 in the Good category measuring Particulate Matter.
Oakridge: The Air Quality Index is 23 in the Good category measuring Particulate Matter.
Cottage Grove: The Air Quality Index is 38 in the Good category measuring Particulate Matter.
Data courtesy of Lane Regional Air Protection Agency (LRAPA.org)
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Eugene-Springfield Area Pollen count:
GRASS: 0 ABSENT
TREES: 2 LOW
WEEDS: 0 ABSENT
Measured 8.11.25
Data courtesy of Oregon Allergy Associates.
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Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis:
- Clear tonight,
- Sunny and a bit cooler Wednesday, mostly clear Wednesday night,
- Mostly sunny and a bit cooler Thursday, partly cloudy in the evening, mostly cloudy late at night,
- Mostly cloudy and a bit cooler with a good (50%) chance of rain Friday, then mostly cloudy with rain likely (70%) Friday night.
- lows 58-57 warming to 63 Friday night highs 90-78.
- Mostly cloudy and a bit warmer with rain likely (70%) Saturday, mostly cloudy with a slight (20%) chancre of rain Saturday night,
- A mix of clouds and sun and a bit warmer Sunday, partly cloudy at night,
- Mostly sunny and a bit warmer Monday, mostly clear Monday night,
- Then sunny and a bit warmer Tuesday.
- highs 79-84 lows 57-53. (seasonal averages high 85 low 52).
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Forecast for the Umpqua Valley including Roseburg:
- Clear tonight,
- Sunny and cooler Wednesday, mostly clear Wednesday night,
- AM clouds with patchy fog, sunny Thursday afternoon, mostly clear in the evening, partly cloudy with a slight (20%) chance of showers late at night,
- Mostly cloudy and a bit cooler with a (0%) chance of showers Friday, mostly cloudy with a (0%) of showers Friday night.
- lows 64-62 warming to 67 Friday night highs 93-84.
- Mostly cloudy and a bit cooler with a (0%) chance of showers Saturday, mostly cloudy with a slight (20%) chance of evening thunderstorms, just mostly cloudy late at night,
- Partly cloudy and a bit warmer Sunday, partly cloudy Sunday night,
- Mostly sunny and a bit cooler Monday, mostly clear Monday night,
- Then mostly sunny anda bit warmer Tuesday.
- highs near 82-86 cooling to 85 Monday warning to 86 Tuesday lows 63-57 (seasonal averages high 86 low 58).
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Forecast for The South Oregon Coast Including Coos Bay and North Bend:
- Becoming mostly cloudy with patchy dense coastal fog late tonight while becoming mostly cloudy inland with patchy fog late tonight,
- Mostly cloudy with patchy AM inland fog, sunny and a bit cooler Wednesday afternoon, mostly clear Wednesday night,
- Mostly cloudy with AM patchy coastal fog while fog while patchy inland AM fog, , sunny Thursday afternoon, partly cloudy in the evening, mostly cloudy with patchy fog and a slight (20%) chance of showers late Thursday night.
- highs near 74 lows 57-62.
- Patchy AM fog, mostly cloudy with a slight (20%) chance of showers Friday afternoon, mostly cloudy with showers likely (70%) Friday night,
- Mostly cloudy with a showers likely (70%) and a bit cooler Saturday afternoon, a slight (20%) chance of evening showers, just mostly cloudy late Saturday night,
- Mostly cloudy start, partly cloudy and a bit warmer Sunday afternoon, partly cloudy Sunday night,
- Then partly cloudy Monday through Tuesday.
- highs 73-75 lows 57-54.
- (seasonal averages high 67 low 54). _______________
Forecast for the Northern Oregon Cascades including the Cascades in Lane County:
- Clear tonight,
- Sunny and a bit cooler Wednesday, mostly clear Wednesday night,
- Sunny and a bit cooler Thursday, partly cloudy at night,
- A mix of clouds and sun and slightly cooler with a slight (20%) chance of rain Friday, then mostly cloudy with a good (50%) chance of rain Friday night.
- free air freezing level 16,000 ft. tonight, 15,000 ft. Wednesday and Wednesday night, 14,000 ft. Thursday and Thursday night, then snow level above 8,000 ft. Friday and Friday night.
- lows 53-48 warming to 52 Friday night highs 78-67.
- Mostly cloudy with a (40%) chance of AM rain and a slight (20%) chance of thunderstorms, a mix of clouds and sun and a bit cooler with a good (50%) chance of rain and a slight (20%) chance of thunderstorms Saturday afternoon, mostly cloudy with a slight (20%) chance of rain Saturday night,
- A mix of clouds and sun and a bit warmer with a slight (20%) chance of rain and thunderstorms Sunday,just partly cloudy Sunday night,
- Mostly sunny and bit warmer Monday, partly cloudy in the evening, mostly clear late Monday night,
- Then sunny and a bit warmer Tuesday.
- snow level above 8,000 ft, Saturday through Sunday, then free air freezing level 13,000 ft Sunday night through Tuesday.
- highs 66-73 lows 49-47
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