Dense Fog Advisory issued December 9 at 8:11PM PST until December 10 at 10:00AM PST by NWS Portland OR

* WHAT…Visibility one quarter mile or less in dense fog.

* WHERE…South Willamette Valley, Lower Columbia River and Cowlitz
River Valleys, Tualatin Valley, Portland West Hills and Chehalem
Mountain, East Central Willamette Valley, and South Washington
Cascade Foothills.

* WHEN…Until 10 AM PST Tuesday.

* IMPACTS…Low visibility could make driving conditions hazardous.