Aug
11.
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 Thursday through Monday show a cold front moves through on Thursday and then another cold front pushes through between Saturday.
ADVISORIES:
- A RED FLAG WARNING IS IN EFFECT FROM 2 PM UNTIL 8 PM TUESDAY 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 TUESDAY 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 TUESDAY 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 TUESDAY 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 TUESDAY 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 TUESDAY NIGHT 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 TUESDAY 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 (still very warm) Tuesday, clear Tuesday night,
- Sunny and a bit cooler Wednesday, mostly clear at night,
- Mostly sunny and a bit cooler Thursday, then partly cloudy Thursday night.
- lows 60-56 warming to 58 Thursday night highs 99-83.
- AM clouds and sun, mostly cloudy and a bit cooler with a slight (20%) chance of rain Friday, mostly cloudy with a (40%) chance of rain Friday night,
- Mostly cloudy with a (40%) chance of rain Saturday, mostly cloudy with a slight (20%) chancre of rain at night,
- A mix of clouds and sun and a bit warmer Sunday, partly cloudy Sunday night,
- Then mostly sunny and a bit warmer Monday.
- highs 83-82 lows 60-56 warming to night. (seasonal averages high 85 low 52).
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Forecast for the Umpqua Valley including Roseburg:
- Clear tonight,
- Sunny and a bit cooler (still Hot)|Tuesday, clear Tuesday night,
- Mostly sunny and cooler Wednesday, mostly clear at night,
- Some AM clouds, sunny Thursday afternoon, mostly clear in the evening, then partly cloudy late Thursday night.
- highs 103-104 cooling to 100 Tuesday lows 65-59.
- Mostly cloudy with a slight (20%) chance of showers Friday, mostly cloudy with patchy fog and a slight (20%) of showers Friday night,
- Mostly cloudy with patchy AM fog, a (0%) chance of showers Saturday afternoon, mostly cloudy with a (0) chance of showers at night,
- Partly cloudy with patchy AM fog, partly cloudy Sunday afternoon and Sunday night,
- Some AM clouds with patchy fog, then sunny Monday afternoon.
- highs near 86-84 lows 58-62 (seasonal averages high 87 low 58).
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Forecast for The South Oregon Coast Including Coos Bay and North Bend:
- Becoming mostly cloudy late with patchy dense coastal fog tonight while becoming mostly cloudy with patchy inland fog late tonight,
- Patchy AM fog, sunny and slightly cooler Tuesday afternoon, mostly clear in the evening, mostly cloudy late Tuesday night with patchy inland fog late Tuesday night,
- Mostly cloudy with patchy AM inland fog, sunny and a bit cooler Wednesday afternoon, mostly clear in the evening, mostly cloudy late at night,
- AM clouds with patchy fog, sunny and a bit cooler Thursday afternoon, partly cloudy in the evening, then mostly cloudy with patchy fog and a slight (20%) chance of showers late Thursday night.
- lows 58-55 highs 77-74.
- Patchy AM fog, mostly cloudy with a slight (20%) chance of showers Friday afternoon, mostly cloudy with patchy fog and a slight (20%) chance of showers Friday night,
- Patchy AM fog, mostly cloudy with a (0%) chance of showers and a bit warmer Saturday afternoon, mostly cloudy with patchy fog and a slight (20%) chance of showers Saturday night,
- Mostly cloudy with areas of AM fog and a slight (20%) chance of showers, partly cloudy Sunday afternoon, partly cloudy with patchy fog late Sunday night,
- Patchy AM fog, then partly cloudy Monday afternoon.
- highs 73-75 cooling back to 73 Sunday lows 57-58.
- (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 Tuesday, clear Tuesday night,
- Sunny and a bit cooler Wednesday, mostly clear at night,
- Sunny and a bit cooler Thursday, then partly cloudy Thursday night.
- free air freezing level above 16,000 ft. falling to 16,000 ft. tonight, 16,000 ft. Tuesday and Tuesday night, 15,000 ft. Wednesday and Wednesday night, then 14,000 ft. Thursday and Thursday night.
- lows 59-47 highs 88-73.
- Mostly sunny and slightly cooler with a slight (20%) chance of rain Friday, mostly cloudy with a slight (20%) chance of rain Friday night,
- Mostly cloudy with a (40%) chance of AM rain and a slight (20%) chance of thunderstorms, a mix of clouds and sun with a (40%) chance of rain and a slight (20%) chance of rain and a slight (20%) chance of thunderstorms Saturday afternoon, mostly cloudy with a slight (20%) chance of rain Saturday night,
- Mostly sunny and a bit warmer with a slight (20%) chance of rain, Sunday, partly cloudy Sunday night,
- Then mostly sunny and bit warmer Monday.
- snow level above 8,000 ft, Friday through Sunday, then free air freezing level 14,000 ft Sunday night and Monday.
- highs 68-73 lows 50-48.
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