A powerful storm system from the Pacific is expected to make landfall in the Wood River Valley Friday night, delivering up to two feet of powder in the central mountains, according to a Thursday morning forecast from the National Weather Service’s Pocatello office.
“Look for high mountain snow at elevations of 7,000 to 8,000 feet,” the office stated. “The heaviest period of precipitation will occur Sunday night through Monday night.”
According to commercial weather forecasting service Accuweather, this particular east-tracking storm from the Pacific is classified as an “atmospheric river,” or a fast-moving band of warm water vapor from the tropics. It could rival the intensity of Atlantic hurricanes, according to AccuWeather Meteorologist Randy Adkins.
Adkins said the storm’s moisture plume has origins from former severe Tropical Storm Namtheun in the western Pacific and “will join forces with a non-tropical system sitting over the northern Pacific on Wednesday.” Rapid strengthening will result, he said.
“As the storm comes together a few hundred miles off the coasts of Washington and British Columbia, its intensification could easily surpass the criteria for bombogenesis [extreme low pressure] … putting the bomb cyclone at or even below the intensity level of Hurricane Larry,” AccuWeather stated in a news release Wednesday, referring to the strong storm that hit the east coast in September.
Though the storm will bring damaging winds with gusts of 40 mph, it will also deliver “greatly needed” precipitation to Idaho, California, Oregon and Washington, AccuWeather stated.
“The snow that accumulates in the mountains may provide bonus runoff into streams this fall or next spring, should snowpack remain in place through the winter,” the service stated.