An Upper Level High Pressure Ridge (“Arch “Shape) weakens and will be replaced by an Upper Level Low Pressure Trough (“U” shape). The graphics for days 1-3 show a cold frontal system moving through the Pacific Northwest today. The graphics for days 3-7 Monday through Friday show a cold front moved through Sunday and then another cold front falls apart as it pushes through Wednesday.
ADVISORIES:
- NONE AT THIS TIME.
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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Measured 8.11.25
Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis:
- Mostly cloudy with a slight (20%) chance of AM rain, a mix of clouds and sun and a bit cooler this afternoon, a good (50%) chance of evening rain, mostly cloudy with showers late tonight,
- Cloudy with AM showers likely (70%), a mix of clouds and sun and a bit cooler with a slight (20%) chance of showers Saturday afternoon, partly cloudy at night,
- Mostly sunny and a bit warmer Sunday, partly cloudy in the evening, then mostly cloudy late Sunday night.
- highs 82-80 warming back to 82 lows 64-55.
- A mix of clouds and sun and a bit warmer Monday, partly cloudy Monday night,
- Sunny and a bit warmer Tuesday,mostly clear at night,
- Sunny and a bit warmer Wednesday, clear Wednesday night,
- Then sunny and a bit warmer Thursday.
- highs 82-87 lows 52-54. (seasonal averages high 85 low 52).
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Forecast for the Umpqua Valley including Roseburg:
- Mostly clear this evening, partly cloudy late tonight,
- AM clouds with a slight (20%) chance of showers, partly cloudy and a bit warmer with a slight (20%) chance of showers Friday afternoon, mostly cloudy with a good (50%) of evening showers, showers likely (70%) late Friday night,
- Mostly cloudy with AM showers likely (70%), a bit cooler with a good (50%) chance of showers Saturday afternoon, mostly cloudy with a slight (20%) chance of evening showers, mostly cloudy late Saturday night,
- Mostly cloudy with a slight (20%) chance of AM showers, partly cloudy and a bit warmer with a slight (20%) chance of thunderstorms Sunday afternoon, partly cloudy in the evening, then mostly cloudy Sunday night.
- highs 87-80 warming to 83 Sunday lows 63-67 cooling to 59 Sunday night.
- Mostly cloudy start, sunny and a bit warmer Monday, mostly clear Monday night,
- Mostly sunny and a bit warmer Tuesday and Wednesday, mostly clear both nights,
- Then mostly sunny and a bit warmer Thursday.
- highs near 84-90 lows 57-59 (seasonal averages high 86 low 57).
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Forecast for The South Oregon Coast Including Coos Bay and North Bend:
- Mostly cloudy with patchy fog and a slight (20%) chance of showers late tonight,
- Patchy AM fog, mostly cloudy and a bit warmer with a slight (20%) chance of showers Friday afternoon, cloudy with evening coastal showers likely (70%) while a good (50%) chance of inland late Friday night while a good (50%) chance of evening showers and inland showers late Friday night,
- Mostly cloudy with AM showers likely (70%), a bit cooler with a slight (20%) chance showers Saturday afternoon, then mostly cloudy Saturday night,
- Mostly cloudy Sunday, then partly cloudy Sunday night.
- lows 58-60 cooling to 54 Sunday night highs 77-73.
- Partly cloudy Monday and Monday night,
- Partly cloudy and a bit warmer Tuesday, mostly clear at night,
- Mostly sunny and a bit warmer Wednesday, mostly clear Wednesday night,
- Then sunny Thursday.
- highs 73-75 lows near 54.
- (seasonal averages high 67 low 54). _______________
Forecast for the Northern Oregon Cascades including the Cascades in Lane County:
- A mix of clouds and sun with a slight (20%) chance of rain and a bit cooler this afternoon, mostly cloudy with a (40%) chance of evening rain, showers likely late tonight,
- Cloudy with AM showers, a mix of clouds and sun and a bit cooler with a good (50%) chance of showers and a slight (20%) chance of thunderstorms Saturday afternoon, mostly cloudy with a (30%) chance of evening showers, just mostly cloudy late Saturday night,
- A mix of clouds and sun and a bit warmer with a slight chance of thunderstorms Sunday, partly cloudy with a slight (20%) chance of evening , then mostly cloudy with a slight (20%) chance of showers late Sunday night.
- free air freezing level 14,000 ft. tonight, then snow level above 8,000 ft. Friday through Saturday night, free air freezing level 13,000 ft. Sunday, then snow level above 8,000 ft. Sunday night.
- lows 47-52 cooling to 49 Saturday night highs 69-62 .
- A mix of clouds and sun Monday, mostly clear Monday night,
- Sunny and a bit warmer Tuesday and Wednesday, mostly clear both nights,
- Then sunny and a bit warmer Thursday.
- free air freezing level 13,000 ft. Monday through Tuesday, 14,000 ft. Tuesday night through Wednesday night, then 15,000 ft.Thursday.
- highs 66-73 lows 49-47.