A strong winter storm will impact southwest Washington and northwest Oregon today through Wednesday. More snow and now high winds are expected with some flooding possible toward the end of the week.
Below are estimates of what we can expect and during what time frames:
Snow
Location: NW OR & SW WA Coast Range
Expected window of when this will occur: Today and Wed
10 to 20 inches
Location: Central Coast Range
Today snow, then rain
6 to 12 inches
Location: Willamette & Lower Columbia Valleys (Mainly Portland Vicinity Northward)
Rain-snow line will shift north during the morning
Prime threat time: Wed (midnight – 8 AM)
Late morning (Clark-Cowlitz)
Wind
Location: Coast Range / Willapa Hills:
40 mph, gusts 80 mph (NW OR Cst Range)
20 mph, gusts 35 mph (Willapa Hills)
Expected Window of when this will occur: Wed (2 AM-4 PM)
Prime threat time: 6 AM-noon
High winds mainly Salem southward
20-30 mph, gusts 45-50 mph
Expected window of when this will occur: Wed (daytime)
Prime threat time: 10 AM – 2 PM
Rain
There is heavy rain potential. Rivers are expected to rise and there is the possibility for minor flooding later this week.
Unknowns
Where the rain/snow line will be
How much snow will fall on the valley floor
A Winter Storm Warning for Columbia County is in effect until 12 PM tomorrow.
Here is the text of the warning:
.COLD AIR HAS SETTLED OVER THE PACIFIC NORTHWEST AND WILL RESULT IN WINTRY WEATHER ACROSS SOUTHWEST WASHINGTON AND NORTHWEST OREGON THROUGH WEDNESDAY. A REINFORCING COLD FRONT WILL CONTINUE TO MOVE ACROSS WASHINGTON AND NORTHERN OREGON TODAY...BRINGING HEAVY SNOW TO THE CASCADES AND THE COLUMBIA RIVER GORGE...ALONG WITH SOME POSSIBLE LIGHT ACCUMULATIONS DOWN TO THE VALLEY FLOOR. A STRONGER LOW PRESSURE PRESSURE SYSTEM WILL THEN MOVE IN FROM THE SOUTHWEST LATE TONIGHT AND WEDNESDAY... SPREADING ABUNDANT MOISTURE OVER THE VERY COLD AIR MASS THAT IS IN PLACE ACROSS THE REGION. THIS WILL RESULT IN MORE HEAVY SNOW FOR THE CASCADES AND COLUMBIA RIVER GORGE...AND MAY BRING ACCUMULATIONS TO THE NORTHERN LOWLANDS AS WELL...INCLUDING THE PORTLAND AND VANCOUVER METRO AREA. DETAILS ARE STILL VERY UNCERTAIN ESPECIALLY FOR THE LOWLANDS...BUT THE POTENTIAL IS THERE FOR THIS TO BE A SIGNIFICANT WINTER WEATHER EVENT.
Precautionary actions
*Be sure your car is stocked with emergency and winter weather supplies
*Have utility companies’ numbers handy in case of power outages
*Have flashlights and other power outage supplies easily accessible
*Stay tuned to your local news and EM social media for updates on the weather
