PORTLAND, Ore. (KOIN) — There will be an increased chance of freezing rain in the interior valleys of Northwest Oregon and Southwest Washington early next week as temperatures in the mid 30s and low 40s persist in the greater Portland area.

KOIN 6 Meteorologists Kelley Bayern and Steve Pierce report that there’s still a lot of uncertainty for next week’s weather forecast. However, the National Weather Service is anticipating the possibility of freezing rain from Dec. 20 to Dec. 22 during the overnight and morning hours.

“Sunday through next week turns more interesting and challenging to forecast as we bring in moisture and keep chilly temperatures around,” Bayern said. “Rain showers arrive Sunday within a quick disturbance, with a shot at snow and mixed showers in Portland come the overnight hours into Monday morning.”

Colder-than normal temperatures are expected through Dec. 23. | NWS

Snow levels may drop to 500 feet of elevation early next week, with little snowfall expected. Rain is forecast to return to the region by Tuesday night, with the possibility of more than an inch falling across the valley. Periods of heavy mountain snow may also be possible, but forecasts remain fickle into next week with little certainty. Hazardous driving conditions will be possible across mountain passes and through the gorge during this time.

“Please do not take any one model or forecast for next week, then never look again expecting it will stay the same,” Portland’s National Weather Service office said. “It is fully expected this forecast will fluctuate … between now and next week.”