TIM CHUEY WEATHER

April 20, 2024

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

• A FLOOD WARNING IS IN EFFECT UNTIL LATE THIS MORNING FOR THE OWYHEE RIVER BELOW THE OWYHEE DAM AFFECTING MALHEUR COUNTY.

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:

An Upper Level High Pressure Ridge  brought the Pacific Northwest sunshine, but change is coming.  The graphics for days 1-3  show a cold front moving through Oregon Saturday for cooling and possible showers. The graphics for days 3-7  Monday through Friday show a frontal system that moves across the Pacific Northwest between Tuesday night and Wednesday.  Another frontal system will push in Friday, then a complex frontal system will be offshore headed our way next Saturday.

Forecast For The South Willamette Valley Including Eugene-Springfield:

• AM sun, becoming mostly cloudy with a good (50%) chance of rain and a bit cooler this afternoon (under 0.10 in. of rain possible), mostly cloudy with a good (50%) chance of evening rain (under 0.10 in. of rain possible), just partly cloudy late tonight,
• Mostly sunny and a bit cooler Sunday, becoming mostly clear at night,
• Mostly sunny and a bit warmer Monday (Earth Day), then mostly cloudy Monday night.
• highs 65-62 warming to 66 Monday lows 39-37 warming to 42 Monday night.
• A mix of clouds and sun and a bit warmer Tuesday, partly cloudy with a slight (20%) chance of evening rain, mostly cloudy with a slight (20%) chance of rain late Tuesday night,
• A mix of clouds and sun with a slight (20%) chance of rain and a bit cooler Wednesday, mostly cloudy with a slight (20%) chance of  showers at night,
• Mostly cloudy and a bit cooler with a good (50%) chance of rain Thursday, showers likely (70%) Thursday night,
• Then mostly cloudy with showers likely (70%) and a bit warmer Friday.
• highs 69-59 warming to 62 Friday lows 42-44. (seasonal averages high 62 low 40)

Forecast for the Umpqua Valley including Roseburg:

• Sunny start, becoming mostly cloudy and a bit cooler with a (30%) chance of rain this afternoon, mostly cloudy with a slight (20%) chance of evening rain, just partly cloudy late tonight,
• Partly cloudy and a bit cooler Sunday and in the evening, mostly cloudy with areas of frost late at night,
• Areas of AM frost, partly cloudy and a bit warmer Monday afternoon (Earth Day), then partly cloudy Monday night.
• highs 69-65 warming to 72 Monday lows 42-39 warming to 44 Monday night.
• Mostly cloudy start, partly cloudy and a bit warmer Tuesday afternoon, partly cloudy with a slight (20%) chance of evening thunderstorms, just mostly cloudy late Tuesday night,
• AM clouds, partly cloudy and a bit cooler with a slight (20%) chance of showers Wednesday afternoon, partly cloudy in the evening, mostly cloudy a (30%) chance of rain at night,
• Mostly cloudy with a slight (20%) chance of AM rain, a bit cooler with a (40%) chance of showers Thursday afternoon, showers likely (70%) Thursday night,
• Then mostly cloudy with showers likely (70%) Friday.
• highs 68-62 lows 43-47. (seasonal averages high 64 low 43)

Forecast for the Oregon Coast including Coos Bay and North Bend:

• AM sun with a slight (20%) chance of coastal rain and mostly cloudy and a bit cooler with coastal rain likely (70%) this afternoon while becoming mostly cloudy inland with a good (50%) chance of inland rain this afternoon (under 0.10 in. of rain possible), a slight (20%) chance of evening rain, just mostly cloudy late tonight,
• Partly cloudy and a bit cooler Sunday and in the evening, mostly clear at night,
• Partly cloudy and a bit warmer Monday (Earth Day), then mostly cloudy Monday night.
• highs 62-59 warming back to 62 Monday lows 40-44.
• Mostly cloudy and a bit cooler Tuesday, mostly cloudy Tuesday night,
• Mostly cloudy with a slight (20%) chance of AM showers, partly cloudy and a bit cooler with a slight (20%) chance of showers  Wednesday afternoon, a slight (20%) chance of rain at night,
• Mostly cloudy with a (30%) of AM rain, a bit warmer with a good (50%) chance of showers Thursday afternoon, showers likely (70%) Thursday night,
• Mostly cloudy with AM showers likely (70%), then a good (50%) chance of showers Friday afternoon.
• highs 58-55 warming to 57 Thursday and Friday lows 43-46. (seasonal average high 57 low 44)

Forecast for the Northern Oregon Cascades including Willamette Pass:

• Mostly sunny and a bit cooler with a good (50%) chance of rain this afternoon, mostly cloudy with evening rain and snow likely (70%), a slight (20%) chance of rain and snow showers late tonight,
• Mostly sunny and cooler Sunday, mostly clear at night,
• Sunny and warmer Monday (Earth Day), partly cloudy in the evening, then mostly cloudy last Monday night.
• snow level 6,500 ft. today, 5,500 ft. falling to 3,500 ft. late tonight, free air freezing level 6,000 ft. Sunday afternoon, 8,000 ft. Sunday night, 9,000 ft. Monday, then 11,o00 ft. Monday night.
• highs 58-50 warming to 62 Monday lows 28-37.
• A mix of clouds and sun and a bit cooler with a slight (20%) chance of rain Tuesday, mostly cloudy with a (30%) chance of rain and snow Tuesday night.
• A mix of clouds and sun and cooler with a (30%) chance of rain showers and snow Wednesday, mostly cloudy with a good (50%) chance of  rain and snow showers at night,
• AM clouds and sun with snow showers likely (70%) and a good (50%) chance of rain, mostly cloudy and a bit cooler with snow showers likely (70%) with a good (50%) chance of rain Thursday afternoon, rain and snow showers likely (70%) Thursday night,
• Then mostly cloudy with rain and snow showers likely (70%) and a bit cooler Friday.
• snow level 7,000 ft. Tuesday, 6,000 ft. Tuesday night, 5,500 ft. Wednesday, 5,00 ft. Wednesday night through Thursday night, then 5,500 ft. Friday.
• highs 60-44 lows 37-33 warming to 35 Thursday night.