TIM CHUEY WEATHER

December 7, 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

• A FLOOD WARNING IS IN EFFECT THROUGH LATE THIS EVENING FOR THE LUCKIAMUTE RIVER NEAR SUVER AFFECTING POLK AND BENTON COUNTIES.
• A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 10 A,M FRIDAY ABOVE 3,000 FT. FOR THE NORTHERN OREGON CASCADES AND THE CASCADES IN LANE COUNTY.
• A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 4 AM FRIDAY ABOVE 3,500 FT. FOR THE SOUTH CENTRAL OREGON CASCADES, THE SISKIYOU MOUNTAINS AND THE SOUTHERN OREGON CASCADES,
• A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 10 AM FRIDAY ABOVE 3,500 FT. FOR THE EAST SLOPES OF THE OREGON CASCADES.
• A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL 10 AM FRIDAY ABOVE 4,000 FT. FOR THE NORTHERN BLUE MOUNTAINS OF OREGON AND THE NORTHWEST BLUE MOUNTAINS.

HEALTH ADVISORIES

• A PUBLIC HEALTH ADVISORY IS IN EFFECT FOR UNSAFE LEVELS OF FECAL BACTERIA IN OCEAN WATERS AT BEVERLY BEACH IN LINCOLN COUNTY. PEOPLE SHOULD AVOID DIRECT CONTACT WITH THE WATER IN THIS AREA UNTIL THE ADVISORY IS LIFTED. UNSAFE LEVELS OF FECAL BACTERIA CAN CAUSE DIARRHEA, STOMACH CRAMPS, SKIN RASHES, UPPER RESPIRATORY INFECTIONS AND OTHER ILLNESSES. CHILDREN, THE ELDERLY, AND THOSE WITH A COMPROMISED IMMUNE SYSTEM SHOULD USE EXTRA CAUTION AS THEY ARE MORE VULNERABLE TO TO ILLNESSES FROM WATERBORNE BACTERIA. VISITORS SHOULD AVOID WADING IN NEARBY CREEKS, POLS OF WATER ON THE BEACH, OR IN DISCOLORED WATER, AND STAY CLEAR OF WATER RUNOFF FLOWING INTO THE OCEAN.
• A RECREATIONAL USE HEALTH ADVISORY HAS BEEN EXPANDED FOR THE AREA FROM THE ROSS ISLAND LAGOON TO RIVERPLACE MARINA IN MULTNOMAH COUNTY DUE TO THE PRESENCE OF A CYANOBACTERIA BLOOM. PEOPLE SHOULD AVOID SWIMMING AND HIGH SPEED WATER ACTIVITIES, SUCH AS WATER SKIING OR POWER BOATING, IN AREAS OF THE LAKE AND SLOUGH WHERE BLOOMS ARE, AS THE MAJOR ROUTE OF EXPOSURE IS INGESTION OF WATER. TOXINS ARE NOT ABSORBED THROUGH THE SKIN, HOWEVER, THOSE WITH SKIN SENSITIVITIES MAY GET A PUFFY RED RASH. THE OREGON HEALTH AUTHORITY ENCOURAGES PEOPLE TO VISIT THE AREA AND ENJOY ACTIVITIES SUCH AS CATCH AND RELEASE FISHING, CAMPING, HIKING, BILKING, PICNICKING, BIRD WATCHING, CANOEING, AND KAYAKING. BOATING IS SAFE AS LONG AS SPEEDS DO NOT CREATE EXCESSIVE WATER SPRAY. SPRAYS COULD LEAD TO THE RISK OF INHALING CYANOTOXINS. DRINKING WATER FROM THE LAKE IS ESPECIALLY DANGEROUS.
• A RECREATIONAL USE HEALTH ADVISORY IS IN EFFECT FOR THE WILLAMETTE RIVER FROM ROSS ISLAND DOWNSTREAM (NORTH) TO THE AREA NEAR CATHEDRAL PARK IN PORTLAND, IN MULTNOMAH COUNTY DUE TO THE PRESENCE OF A CYANOBACTERIA BLOOM. PEOPLE SHOULD AVOID SWIMMING AND HIGH SPEED WATER ACTIVITIES, SUCH AS WATER SKIING OR POWER BOATING, IN AREAS OF THE LAKE AND SLOUGH WHERE BLOOMS ARE, AS THE MAJOR ROUTE OF EXPOSURE IS INGESTION OF WATER. TOXINS ARE NOT ABSORBED THROUGH THE SKIN, HOWEVER, THOSE WITH SKIN SENSITIVITIES MAY GET A PUFFY RED RASH. THE OREGON HEALTH AUTHORITY ENCOURAGES PEOPLE TO VISIT THE AREA AND ENJOY ACTIVITIES SUCH AS FISHING, CAMPING, HIKING, BILKING, PICNICKING, BIRD WATCHING, CANOEING, AND KAYAKING. BOATING IS SAFE AS LONG AS SPEEDS DO NOT CREATE EXCESSIVE WATER SPRAY. SPRAYS COULD LEAD TO THE RISK OF INHALING CYANOTOXINS.DO NOT DRINK THE WATER.
• A RECREATIONAL USE HEALTH ADVISORY CONTINUES IN EFFECT FOR ARRONS LAKE, BUT HAS BEEN LIFTED FOR PETE’S SLOUGH AND STURGEON LAKE ON SAUVIE ISLAND DUE TO THE PRESENCE OF A CYANOBACTERIA BLOOM. PEOPLE SHOULD AVOID SWIMMING AND HIGH SPEED WATER ACTIVITIES, SUCH AS WATER SKIING OR POWER BOATING, IN AREAS OF THE LAKE AND SLOUGH WHERE BLOOMS ARE, AS THE MAJOR ROUTE OF EXPOSURE IS INGESTION OF WATER. TOXINS ARE NOT ABSORBED THROUGH THE SKIN, HOWEVER, THOSE WITH SKIN SENSITIVITIES MAY GET A PUFFY RED RASH. THE OREGON HEALTH AUTHORITY ENCOURAGES PEOPLE TO VISIT THE AREA AND ENJOY ACTIVITIES SUCH AS FISHING, CAMPING, HIKING, BILKING, PICNICKING, BIRD WATCHING, CANOEING, AND KAYAKING. BOATING IS SAFE AS LONG AS SPEEDS DO NOT CREATE EXCESSIVE WATER SPRAY. SPRAYS COULD LEAD TO THE RISK OF INHALING CYANOTOXINS.
• A RECREATIONAL USE HEALTH ADVISORY IS IN EFFECT FOR AGENCY LAKE AND EXTENDED THE ADVISORY FOR THE SOUTHERN PORTION OF UPPER KLAMATH LAKE, FROM HOWARD’S BAY SOUTH TO THE LINK RIVER DAM  IN KLAMATH COUNTY DUE TO THE PRESENCE OF A CYANOBACTERIA BLOOM. PEOPLE SHOULD AVOID SWIMMING AND HIGH SPEED WATER ACTIVITIES, SUCH AS WATER SKIING OR POWER BOATING, IN AREAS OF THE RESERVOIR WHERE BLOOMS ARE, AS THE MAJOR ROUTE OF EXPOSURE IS INGESTION OF WATER. TOXINS ARE NOT ABSORBED THROUGH THE SKIN, HOWEVER, THOSE WITH SKIN SENSITIVITIES MAY GET A PUFFY RED RASH. THE OREGON HEALTH AUTHORITY ENCOURAGES PEOPLE TO VISIT AND ENJOY ACTIVITIES SUCH AS FISHING, CAMPING, HIKING, BILKING, PICNICKING, BIRD WATCHING, CANOEING, AND KAYAKING. BOATING IS SAFE AS LONG AS SPEEDS DO NOT CREATE EXCESSIVE WATER SPRAY. SPRAYS COULD LEAD TO THE RISK OF INHALING CYANOTOXINS.
• 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

Frontal systems are moving through Oregon bringing rain and they will be pushed by Atmospheric Rivers. The graphics for days 1-3  show a warm front slowly pushing through the Pacific Northwest Saturday. The graphics for days 3-7  Sunday through Thursday show frontal systems sliding through Oregon Sunday and next Thursday.

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Forecast For The South Willamette Valley Including Eugene-Springfield:

• Mostly cloudy with showers and a slight (20%) chance of thunderstorms tonight (0.25 in. of rain possible, thunderstorms, small hail possible),
• Clouds and sun with a good (50%) chance of AM showers, a mix of clouds and sun with a (30%) chance of showers Friday afternoon (under 0.10 in. of rain possible), partly cloudy with patchy evening frost, mostly cloudy with a (40%) chance of rain and snow and widespread frost late Friday night,
• Mostly cloudy with a good (50%) of AM rain, rain likely (70%) Saturday afternoon (0.10 in. of rain possible), rain Saturday night (0.25 in. of rain possible),
• Mostly cloudy with rain and a bit warmer Sunday, then rain Sunday night.
• lows 38-32 warming to 45 Sunday night highs 48-53.
• Mostly cloudy with a good (50%) of rain Monday, partly cloudy with a slight (20%) chance of evening rain, just mostly cloudy Monday night,
• A mix of clouds and sun and a bit cooler Tuesday, partly cloudy  at night,
• Clouds and sun with a slight (20%) chance of AM rain, a mix of clouds and sun with a (40%) chance of rain Wednesday afternoon, mostly cloudy with a (40%) chance of rain Wednesday night,
• Mostly cloudy with a slight (20%) chance of AM rain, then partly cloudy with a slight (20%) chance of rain Thursday afternoon.
• highs 53-50 lows 38-35 warming to 37 Wednesday night. (seasonal averages high 47 low 35)

Forecast for the Umpqua Valley including Roseburg:

• Mostly cloudy with showers and snow showers with a slight (20%) chance of thunderstorms tonight (under 0.10 in. of rain possible, snow level 3,000 ft. falling to 2,500 ft., no snow accumulation expected),
• Mostly cloudy with patchy dense fog and a (50%) chance of AM rain and snow showers (under 0.10 in. of rain possible, snow level 2,500 ft.), just mostly cloudy and a bit cooler Friday afternoon, a patchy fog with  a slight (20%) chance of rain and snow late Friday night,
• Mostly cloudy with areas of AM fog, mostly cloudy and a bit warmer with a (30%) chance of rain rain Saturday afternoon, a good (50%) chance of evening rain, rain likely (70%) late at night (0.10 in. of rain possible),
• Mostly cloudy with rain, a bit warmer Sunday, then rain Sunday night.
• lows 40-35 warming to 46 Sunday night highs 46-52.
• Mostly cloudy with AM rain likely (70%), a good (50%) chance of rain Monday afternoon, a slight (20%) chance of evening rain, just mostly cloudy late Monday night,
• Partly cloudy Tuesday partly cloudy at night,
• Mostly cloudy with a slight (20%) chance of rain Wednesday, a (30%) chance of rain Wednesday night,
• Mostly cloudy with a slight (20%) chance of AM rain, then partly cloudy with a slight (20%) chance of rain Thursday afternoon.
• highs near 52 lows 40-37 warming to 39 Wednesday night. (seasonal averages high 48 low 37)

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

• Mostly cloudy with coastal showers and a slight (20%) chance of thunderstorms tonight while inland evening showers likely (70%) and a slight (20%) chance of thunderstorms with inland showers likely (70%) late tonight (0.10 in. of rain possible),
• Mostly cloudy with AM coastal showers likely (70%) and a slight (20%) chance of thunderstorms while inland AM showers likely (70%), just mostly cloudy and a bit warmer Friday afternoon (under 0.10 in. of rain possible), mostly cloudy with a slight (20%) chance of coastal rain late at night while partly cloudy inland in the evening and mostly cloudy with a slight (20%) chance of inland rain late Friday night,
• Mostly cloudy with a (30%) chance of rain and a bit warmer Saturday (under 0.10 in. of rain possible), evening coastal rain likely (70%) and coastal rain late at night while a good (50%) chance of evening inland rain and inland rain likely (70%) late at night (0.10 in. of rain possible),
• Mostly cloudy with rain and a bit warmer Sunday, then rain Sunday night .
• lows 42-37 warming to 47 Sunday night highs 55-59.
• Mostly cloudy and a bit cooler with a good (50%) chance of rain Monday, partly cloudy with a slight (20%) chance of evening rain, just partly cloudy late Monday night,
• Some AM clouds, mostly sunny and a bit warmer Tuesday afternoon,  mostly clear in the evening, partly cloudy late at night,
• Mostly cloudy and a bit cooler with a (30%) chance of rain Wednesday, a (40%) chance of rain Wednesday night,
• Mostly cloudy with a (30%) chance of AM rain, then partly cloudy with a (30%) chance of rain Thursday afternoon.
• highs 58-60 lows near 42. (seasonal averages high 53 low 41)

Forecast for the Northern Oregon Cascades including Willamette Pass:

• Mostly cloudy with evening showers and a slight (20%) chance of thunderstorms (possible hail), snow showers tonight (0.50 in. of rain possible, 4-8 in.of snow possible),
• Clouds and sun with AM snow showers likely (70%), a mix of clouds and sun and a bit cooler with widespread frost and a (40%) chance of snow showers Friday afternoon (2 in. of snow possible), partly cloudy with widespread evening frost, a slight (20%) chance of snow late Friday night,
• Mostly cloudy with a good (50%) chance of snow and  rain and warmer Saturday, rain with snow likely (70%) at night,
• Mostly cloudy with AM rain and snow, rain and a bit warmer Sunday afternoon, then rain Sunday night.
• snow level 2,500 ft. tonight and Friday, 1,500 ft. Friday night, 2,000 ft. rising to 4,500 ft. Saturday afternoon, 6,000 ft. Saturday night, 6,500 ft. Sunday, then 6,000 ft. Sunday night.
• lows 23-17 warming to 32 Sunday night highs near 28-38.
• Mostly cloudy and a bit cooler with rain and snow likely (70%) Monday, partly cloudy with a (40%) chance of evening rain and snow, a slight (20%) chance of snow late Monday night,
• Partly cloudy with a slight (20%) chance of AM snow and rain, a bit cooler with a slight (20%) chance of rain Tuesday afternoon, just partly cloudy at night,
• Partly cloudy with a slight (20%) chance of AM rain, a bit warmer with a (40%) chance of rain and a slight (20%) chance of snow Wednesday afternoon, partly cloudy with a (40%) chance of rain and snow Wednesday night,
• Clouds and sun with a (30%) chance of AM rain and snow, then just a mix of clouds and sun Thursday afternoon.
• snow level  5,500 ft. Monday, 4,500 ft. Monday night, 5,000 ft. Tuesday, free air freezing level 11,000 ft.. Tuesday night, snow level 6,000 ft. Wednesday, 5,500 ft. Wednesday night, then 5,000 ft. Thursday.
• highs 37-39 lows 26-24 warming back to 26 Wednesday night.