Dense Fog, Air Stagnation Advisories Issued by National Weather Service

Forecasters with the National Weather Service issued a Dense Fog Advisory for Friday morning due to visibility at less than a quarter mile, urging drivers to use caution during the Friday morning commute.

The National Weather Service said the advisory was issued because the limited visibility poses a danger to drivers, and the fog may last all day Friday.

The NWS has also extended an Air Stagnation Advisory until noon Tuesday, Jan. 22. An Air Stagnation advisory is issued when limited movement of air in a given area may lead to unhealthy levels of air pollution. A Stage 1 Burn Ban for King County was lifted at 1 p.m. yesterday, but bans remain in place in Snohomish and Pierce counties.

Here's the advisory:

...DENSE FOG ADVISORY IN EFFECT UNTIL NOON PST FRIDAY... ...AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL NOON PST TUESDAY...

THE NATIONAL WEATHER SERVICE IN SEATTLE HAS ISSUED A DENSE FOG ADVISORY...WHICH IS IN EFFECT UNTIL NOON PST FRIDAY.

* TIMING...TONIGHT AND FRIDAY MORNING.

* VISIBILITY...LESS THAN A HALF MILE IN MOST AREAS AND LOCALLY NEAR ZERO.

* IMPACTS...LOW VISIBILITY WILL CREATE DIFFICULT DRIVING CONDITIONS AND FREEZING TEMPERATURES WILL CREATE LOCALLY ICY ROADS. STAGNANT CONDITIONS IN THE LOWER ATMOSPHERE WILL ALLOW POLLUTANTS...SUCH AS WOOD SMOKE AND VEHICLE EMISSIONS...TO INCREASE NEAR THE SURFACE.

* RESTRICTIONS/BURN BANS...CHECK WITH YOUR LOCAL AIR QUALITY AGENCY FOR ANY RESTRICTIONS IN YOUR AREA. PRECAUTIONARY/PREPAREDNESS ACTIONS...

AN AIR STAGNATION ADVISORY MEANS THAT LIMITED MOVEMENT OF THE AIR MASS OVER THE ADVISORY AREA WILL ALLOW POLLUTION TO INCREASE TO DANGEROUS LEVELS. PERSONS WITH RESPIRATORY ILLNESS SHOULD FOLLOW THEIR PHYSICIANS ADVICE FOR DEALING WITH HIGH LEVELS OF AIR POLLUTION.

A DENSE FOG ADVISORY MEANS VISIBILITIES WILL FREQUENTLY BE REDUCED TO LESS THAN ONE QUARTER MILE. IF DRIVING...SLOW DOWN... USE YOUR HEADLIGHTS...AND LEAVE PLENTY OF DISTANCE AHEAD OF YOU.