TIM CHUEY WEATHER

April 28, 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.

(NOTE: I won’t be able to publish my forecasts starting April 30th Due to shoulder surgery. I’ll resume as soon as possible.).

ADVISORIES

• A WINTER WEATHER ADVISORY IS IN EFFECT FROM 8 PM TONIGHT UNTIL 11 AM MONDAY FOR THE NORTH OREGON CASCADES, THE CASCADES OF MARION AND LINN COUNTIES, AND THE CASCADES OF LANE COUNTY.
• A WINTER WEATHER ADVISORY IS IN EFFECT FROM 11 PM TONIGHT UNTIL 11 AM MONDAY ABOVE 4,000 FT. THE EAST SLOPES OF THE OREGON CASCADES.FOR
• A FLOOD WARNING IS IN EFFECT UNTIL WEDNESDAY MORNING FOR THE OWYHEE RIVER BELOW THE OWYHEE DAM AFFECTING MALHEUR COUNTY.
• A FREEZE WATCH IS IN EFFECT FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR EASTERN CURRY COUNTY AND AND JOSEPHINE 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 Low Pressure Trough (“U” shape) sitting right over the Pacific Northwest. The graphics for days 1-3  show a frontal system that slid through Pacific Northwest today. The graphics for days 3-7    Wednesday through Monday show the frontal systems that will be moving across the Pacific Northwest through the period.

Forecast For The South Willamette Valley Including Eugene-Springfield:

• Mostly cloudy with a slight (20%) chance of evening showers, showers with a slight (20%) chance of thunderstorms late tonight (0.10 in. of rain possible, more in storms),
• AM clouds with showers and a slight (20%) chance of thunderstorms, a mix of clouds and sun with a slight (20%) chance of showers and thunderstorm and a slightly cooler Monday (0.10 in. of rain possible), a good (50%) chance of evening showers, showers likely (70%) late Monday night (under 0.10 in. of rain possible),
• Mostly cloudy and bit cooler with showers and a slight (20%) chance of thunderstorms Tuesday, partly cloudy with a slight (20%) chance of evening showers, just partly cloudy at night,
• Mostly sunny and a bit warmer Wednesday, then partly cloudy with a slight (20%) chance of showers Wednesday night.
• lows 43-37 warming to 42 Wednesday night highs 56-63.
• A mix of clouds and sun and a bit warmer with a (30%) chance of showers Thursday, partly cloudy Thursday night,
• Mostly sunny and a bit warmer Friday, mostly cloudy with a (40%) chance of showers at night,
• Mostly cloudy and a bit cooler with a good (50%) chance of showers Saturday, a (50%) chance of showers Saturday night,
• Then a mix of clouds and sun and a bit cooler with a good (50%) chance of showers Sunday.
• highs 65-69 cooling to 62 Sunday lows 42-47 (seasonal averages high 64 low 42)

Forecast for the Umpqua Valley including Roseburg:

• Mostly cloudy with a good (50%) of evening showers, a good (50%) chance of showers changing to showers with a slight (20%) chance of thunderstorms late tonight (under 0.10 in. of rain possible, snow level 3,000 ft. late tonight),
• Mostly cloudy with AM rain showers and snow showers and a slight (20%) chance of thunderstorms, a good (50%) chance of showers and a bit cooler with a slight (20%) chance of thunderstorms Monday afternoon (under o.10 in. of rain possible, snow level 3,000 ft., no snow accumulation expected), partly cloudy with a (30%) chance of rain and snow showers late Monday night (snow level 2,500 ft.),
• Mostly cloudy with a AM rain and snow showers likely (70%), a slight (20%) chance of showers Tuesday afternoon, partly cloudy with a slight (20%) chance of evening showers, partly cloudy with patchy frost late at night,
• Areas of AM frost, sunny and a bit warmer Wednesday afternoon, mostly clear in the evening, then partly cloudy with a slight (20%) chance of showers Wednesday night.
• lows 44-39 warming to 42 Tuesday night highs 57-66.
• Partly cloudy and a bit warmer with a slight (20%) chance of showers Thursday, just partly cloudy Thursday night,
• Partly cloudy and a bit warmer Friday, a slight (20%) chance of evening showers, mostly cloudy with a slight (20%) chance of showers late at night,
• Mostly cloudy and a bit cooler with a good (50%) chance of showers Saturday, a (40%) chance of showers Saturday night,
• Then mostly cloudy and a bit cooler with a (40%) chance of showers Sunday.
• highs 69-74 cooling to 64 Sunday lows 45-49 cooling to 47 Saturday night. (seasonal average high 67 low 45)

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

• Mostly cloudy with a slight (20%) chance of evening coastal showers and coastal showers and a slight (20%) of thunderstorms late tonight while a  (30%) chance of inland evening showers and inland showers with inland showers and a slight (20%) chance  of thunderstorms late tonight (0.10 in. of rain possible),
• Mostly cloudy with AM showers and a slight (20%) chance of showers and a slight (20%) chance of thunderstorms, partly cloudy and slightly cooler with a slight (20%) chance of thunderstorms Monday afternoon (under 0.10 in. of rain possible), partly cloudy in the evening, mostly cloudy with a (30%) chance of showers late Monday night (under 0.10 in. of rain possible),
• Mostly cloudy with AM coastal showers likely (70%), a bit warmer with a (50%) chance of showers Tuesday afternoon while a (40%) chance of inland showers at night,
• Sunny and a bit warmer Wednesday, then partly cloudy with a slight (20%) chance of showers Wednesday night.
• lows 43-38 warming to 42 Wednesday night highs 55-62.
• Partly cloudy with a slight (20%) chance of showers Thursday, partly cloudy with a slight (20%) chance of evening showers, just partly cloudy late Thursday night,
• Partly cloudy and a bit warmer Friday, partly cloudy with a slight (20%) chance of evening rain, mostly cloudy with a (20%) chance of showers late at night,
• Mostly cloudy and a bit cooler with a good (50%) chance of  showers Saturday, a good (50%) chance of showers Saturday night,
• Then mostly cloudy with a good (50%) chance of showers Sunday.
• highs 62-64 cooling to 59 Saturday and Sunday lows 43-46. (seasonal average high 58 low 46)

Forecast for the Northern Oregon Cascades including Willamette Pass:

• Mostly cloudy with a good (50%) chance of evening rain and snow showers, rain and snow showers late tonight (0.50 in. of rain possible, 1 in. of snow possible),
• Mostly cloudy with AM rain and snow showers and a slight (20%) chance of thunderstorms (0.50 in. of rain possible, 2-4 in. of snow possible, snow possibly heavy at times),  a bit cooler with a good (50%) chance of rain and snow showers Monday afternoon (AM snow possibly heavy at times), snow and rain showers Monday night (0.50 in. of rain possible, 1 in of snow possible),
• Mostly cloudy and a bit warmer with snow and rain showers Tuesday, evening snow showers likely (70%)  and a good (50%) chance of rain and snow showers with a slight (20%) chance of snow showers at night,
• Sunny and warmer Wednesday, partly cloudy with evening snow showers likely (70%) and a slight (20%) chance of rain showers, then partly cloudy with a slight (20%) chance of rain and snow showers late Wednesday night.
• snow level 3,500 ft. tonight, 3,000 ft. Monday, 2,500 ft. Monday night, 2,500 ft. rising to  4,000 ft. Tuesday afternoon, 3,000 ft. Tuesday night, free air freezing level 5,500 ft. Wednesday, then snow level 5,000 ft. 5,000 ft. Wednesday night,
• lows 28-25 warming to 30 Wednesday night highs 36-48.
• A mix of clouds and sun with a (40%) chance of rain and snow showers and a bit warmer Thursday, mostly cloudy with a (40%) chance of evening rain and snow showers, partly cloudy with a slight (20%) chance of showers late Thursday night,
• Mostly sunny and a bit warmer Friday, partly cloudy with a (40%) chance of evening showers, mostly cloudy with a (40%) chance of showers late at night,
• AM clouds and sun with with a good (50%) chance of showers, a mix of clouds and sun and a bit cooler with a good (50%) chance of showers Saturday afternoon, mostly cloudy with showers likely (70%) and a slight (20%) chance of snow showers Saturday night,
• Then mostly cloudy with rain and snow showers likely (70%) and a bit cooler Sunday.
• snow level  5,500 ft. Thursday, 6,500 ft. Thursday night, free air freezing level 9,000 ft. Friday, snow level 7,500 Friday night, 7,000 ft. Saturday, 6,000 ft. Saturday night, then 5,500 ft. Sunday.
• highs 52-59 cooling back to 52 Sunday lows 32-38 cooling to 34 Saturday night.