Dense Fog Advisory issued November 27 at 8:37PM PST until November 28 at 10:00AM PST by NWS Portland OR

* WHAT…For the Dense Fog Advisory, visibility one quarter mile or
less in dense fog. For the Air Stagnation Advisory, a persistent
inversion with light and variable winds will lead to a period of
stagnant air conditions. This scenario could result in the build
up of air pollutants near the surface over time.

* WHERE…Central Willamette Valley.

* WHEN…For the Dense Fog Advisory, until 10 AM PST Thursday. For
the Air Stagnation Advisory, until 4 PM PST Tuesday.

* IMPACTS…Deteriorating air quality may cause issues for people
with respiratory problems. Low visibility could make driving
conditions hazardous.