Here's the full story (in all caps, 'cause when weather gets real, there's no time for proper capitalization):
...STAGNANT AIR CONDITIONS TO REMAIN INTO EARLY SATURDAY IN
PORTIONS OF WASHINGTON WITH DENSE FREEZING FOG IN PORTIONS OF
OREGON THIS AFTERNOON THROUGH WEDNESDAY MORNING...
.A COLD STABLE LOW-LEVEL AIR MASS WILL LEAD TO STAGNANT AIR
CONDITIONS AND MINIMAL MIXING THROUGH EARLY SATURDAY MORNING IN
THE YAKIMA AND KITTITAS VALLEYS. MEANWHILE AREAS OF DENSE FREEZING
FOG WILL CONTINUE THROUGH WEDNESDAY MORNING ACROSS PORTIONS OF
CENTRAL AND NORTHERN OREGON.
...FREEZING FOG ADVISORY IN EFFECT UNTIL 4 AM PST WEDNESDAY...
THE NATIONAL WEATHER SERVICE IN PENDLETON HAS ISSUED A FREEZING
FOG ADVISORY...WHICH IS IN EFFECT UNTIL 4 AM PST WEDNESDAY.
* TIMING: AREAS OF DENSE FREEZING FOG WILL PERSIST THROUGH EARLY
WEDNESDAY MORNING.
* VISIBILITY: LESS THAN ONE QUARTER MILE AT TIMES.
* IMPACTS: LOW VISIBILITIES WILL MAKE DRIVING DIFFICULT. FREEZING
ROAD SURFACES WILL BECOME SLICK AND HAZARDOUS.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A FREEZING 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.
ALSO...BE ALERT FOR FROST ON BRIDGE DECKS CAUSING SLIPPERY ROADS.
See also: "Wintry Mix"
...WINTRY MIX EXPECTED ACROSS CENTRAL OREGON TONIGHT AND
WEDNESDAY MORNING...
.MIXED PRECIPITATION WILL SPREAD NORTH ACROSS THE AREA THIS
EVENING AND CONTINUE INTO WEDNESDAY MORNING BEFORE TAPERING OFF.
...WINTER WEATHER ADVISORY IN EFFECT FROM 10 PM THIS EVENING TO
10 AM PST WEDNESDAY...
THE NATIONAL WEATHER SERVICE IN PENDLETON HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...SLEET...AND FREEZING RAIN WHICH IS IN
EFFECT FROM 10 PM THIS EVENING TO 10 AM PST WEDNESDAY.
* SNOW ACCUMULATIONS: UP TO 1 INCH OF SNOW AND SLEET ACCUMULATION.
* ICE ACCUMULATION: UP TO .1 INCH OF ICE ACCUMULATION.
* ELEVATION: ALL ELEVATIONS.
* TIMING: BEGINNING BY LATE THIS EVENING AND CONTINUING INTO
WEDNESDAY MORNING BEFORE TAPERING OFF.
* LOCATIONS INCLUDE: BEND...MADRAS...PRINEVILLE...REDMOND
* IMPACTS: ROADS WILL BECOME SNOW AND ICE COVERED AND HAZARDOUS
FOR TRAVEL.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...SLEET...OR
FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.