A winter storm warning has been issued for the Cascades in Northern Oregon and Lane County, as an incoming storm is expected to drop several feet of mountain snow along mountain passes between 8 p.m. Friday and 11 p.m. Sunday.

KOIN 6 Meteorologist Kelley Bayern reports that the region could see as much as 4 feet of mountain snow over the weekend.

“Significant mountain snowfall returns to the mountains tonight,” Bayern said. “Expect up to 4 feet of snowfall through Sunday evening. 

Drivers navigating local mountain passes during this time are urged to use extreme caution. The National Weather Service warns that drivers should only travel the passes out of necessity, and asks that travelers bring emergency flashlights, food, and water.

“Travel could be very difficult,” The NWS states. “Patchy blowing snow could significantly reduce visibility. Those with recreation plans in the Cascades this weekend should prepare for peak winter conditions.”

Weekend snow forecast. (KOIN 6 News)

Cascade Mountain Pass Forecast:

  • Friday night: 8 to 12 inches of snow
  • Saturday: 10 to 20 inches of snow 
  • Sunday: 4 to 8 inches of snow

Periods of heavy rain and potential thunderstorms are in the forecast for the Portland metro area and the rest of the Willamette Valley over the weekend.

“Expect rain showers to trickle in by midday with steady rain by dinnertime,” Bayern said. “The heaviest rain arrives by the later evening hours throughout early Saturday morning.”

Rain forecast. (KOIN 6)

The weather also has the potential to be a hodgepodge of conditions in Portland, with hail, snow and occasional periods of sunshine peeking through the clouds will be possible. Snow levels are expected to drop to 1,000 feet of elevation on Sunday morning.

Mixed showers of rain and snow will be possible in the city during the early Monday morning hours as temperatures are expected to drop into the mid 30s. These conditions are not expected to have a significant impact on city roads.