A Winter Storm Warning remains in effect through 10:00 p.m. Monday for mountain areas in much of southern Oregon. Forecasters at the National Weather Service said an atmospheric river and stationary front will continue to bring impactful weather to the region through Monday. The snowfall accumulation will be unusually high east of the Cascades and over the Siskiyou Summit through this event. Snow will continue to accumulate into Tuesday, although the locations, intensity and elevations will change…