Yet another storm front is expected to dump up to a foot of snow on Interstate 5's Siskiyou Summit and up to 2 feet at Diamond Lake beginning Tuesday while bringing heavy rains and winds to the Rogue Valley, authorities said.
The National Weather Service forecasts that the snow level will fluctuate today through Wednesday morning between 2,500 feet above sea level to 3,500 feet, leaving heavy snowfalls in higher mountain areas but no snow forecast for I-5 passes north of Medford.
However, those heading south into Northern California can expect "significant" travel impacts along I-5’s Siskiyou Summit and Mt. Shasta City as well as along Highway 140 in the Fish Lake-Lake of the Woods area, according to the weather service.
This front moving down from Alaska is cold enough to withstand the normal warming effect of the Pacific, weather service meteorologist Sven Nelaimischkies said.
“We’re in a polar-vortex type of situation,” Nelaimischkies said. “That’s what’s bringing in this cold air mass and all this snow.”
The storm is expected to drop about two-thirds of an inch of rain by Wednesday afternoon in Medford, three-fourths of an inch of rain in Ashland and more than an inch of rain in Grants Pass, according to the weather service.
Winds are also expected to gust up to 20 mph in Medford and 30 mph in Ashland, according to the weather service.
Forecasts also call for up to 30 inches of new snow at Crater Lake but only 6 new inches in Klamath Falls.
The storm series is also expected to pack a wet and windy punch to Oregon’s South Coast, with 3.29 inches of rain forecast for Brookings by late Wednesday afternoon and 3.67 inches by then in Gold Beach.
However, no main-stem river flooding was expected as of Monday afternoon.
This storm is the latest infusion to Western Oregon’s once anemic snowpack that has suffered from warm, dry weather for much of the winter.
The Rogue River Basin snowpack was just two-thirds of average Feb. 6 before this weekend’s snows, which jumped the snowpack to 74 percent of average Monday morning, according to the federal Natural Resources Conservation Service.