May 30, 2023
Note: Weather is a constantly changing phenomenon and weather forecasting is a combination of science, experience, and intuition. The accuracy of any given forecast can chance due to unexpected changes in atmospheric conditions, so there are no guarantees the the actual weather will conform to the projected forecast.
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.
THE WEATHER PATTERN
A weak Upper Level High Pressure Ridge (“Arch” shape) offshore keeps the onshore airflow going bringing cooler air to Oregon. The graphics for days 1-3 show no fronts moving over the Pacific Northwest. The graphics for days 3-7 Friday through next Tuesday show a frontal system hanging offshore then moving in Saturday and Sunday.
Forecast For The South Willamette Valley Including Eugene-Springfield:
- Mostly clear tonight,
- Mostly sunny and a bit warmer Wednesday, mostly clear Wednesday night,
- Mostly sunny and a bit warmer Thursday, clear at night,
- Sunny and a bit warmer Friday, then clear Friday night.
- lows 42-45 highs 68-75.
- Sunny and a bit warmer Sunday, mostly clear Sunday night,
- Then mostly sunny and a bit warmer Monday and Tuesday, mostly clear both nights,
- highs 77-86 lows near 48-52. (seasonal averages high 70 low 46)
Forecast for the Umpqua Valley including Roseburg:
- Mostly clear this evening, partly cloudy late tonight,
- Sunny and a bit warmer Wednesday, mostly clear Wednesday night,
- Then sunny and a bit warmer Thursday and Friday, clear both nights.
- lows 48-46 warming back to 48 Friday night highs 72-78.
- Sunny and a bit warmer Saturday, clear Saturday night,
- Mostly sunny and a bit warmer Sunday, mostly clear at night,
- Mostly sunny and a bit warmer with a slight (20%) chance of thunderstorms Monday, partly cloudy with a slight (20%) chance of evening thunderstorms, just partly cloudy Monday night,
- Mostly sunny with a slight (20%) chance of thunderstorms Tuesday afternoon.
- highs 80-88 lows 50-56. (seasonal averages high 73 low 50)
Forecast for the Oregon Coast including Coos Bay and North Bend:
- Mostly clear this evening, partly cloudy late tonight,
- Sunny Wednesday, mostly clear in the evening, partly cloudy late Wednesday night,
- Sunny and a bit warmer Thursday, mostly clear at night,
- Mostly sunny and a bit warmer Friday, then mostly clear Friday night.
- lows near 45 highs 59-62.
- Mostly sunny Saturday, mostly clear Saturday night,
- Mostly sunny and a bit warmer Sunday, mostly clear at night,
- AM sun, partly cloudy and a bit warmer Monday afternoon and Monday night,
- Then sunny Tuesday.
- highs 64-67 lows near 48. (seasonal averages high 62 low 50)
Forecast for the Northern Oregon Cascades including Willamette Pass:
- Partly cloudy tonight,
- Mostly sunny and a bit cooler Wednesday, mostly clear Wednesday night,
- Mostly sunny and a bit warmer Thursday, clear at night,
- Sunny and a bit warmer Friday, then clear Friday night.
- free air freezing level 11,000 ft. tonight, 10,000 ft. falling to 9,000 ft. Wednesday afternoon, 9,000 ft. Wednesday night, 9,000 ft. rising to 10,000 ft. Thursday afternoon, 1o,000 ft. Thursday night, 11,000 ft. Friday, then 12,000 ft. Friday night.
- lows 33-37 highs 56-66.
- Sunny and a bit warmer Saturday, clear Saturday night,
- Mostly sunny and a bit warmer Sunday, partly cloudy with a slight (20%) chance of evening rain, partly cloudy late at night,
- AM sun, then partly cloudy and a bit warmer with a slight (20%) chance of rain Monday afternoon, a (30%) chance of evening rain, just partly cloudy late Monday night,
- AM sun, then partly cloudy and a bit warmer with a (40%) chance of rain Tuesday afternoon.
- free air freeing level 12,000 ft. Saturday through Sunday, then snow level above 8,000 ft. Sunday night through Tuesday.
- highs 70-79 cooling to 77 Tuesday lows 40-48.