AIR STAGNATION ADVISORY
Issue Date: 945 AM PST SAT DEC 26 2009
Expiration: 1000 AM PST MON DEC 28 2009

...AIR STAGNATION ADVISORY NOW IN EFFECT UNTIL 10 AM PST MONDAY...
...WIND ADVISORY IS CANCELLED...
THE NATIONAL WEATHER SERVICE IN SEATTLE HAS CANCELLED THE WIND
ADVISORY. THE AIR STAGNATION ADVISORY IS NOW IN EFFECT UNTIL
10 AM PST MONDAY.
* WINDS IN THE LOCAL SEATTLE...TACOMA...BREMERTON AREA ARE NOT
  EXPECTED TO EXCEED WIND ADVISORY CRITERIA.
* STRONG HIGH PRESSURE ALOFT WILL PERSIST OVER THE REGION TODAY.
  THIS WILL TRAP COLD AIR NEAR THE SURFACE UNDER WARM AIR ALOFT.
* THE RESULTING LACK OF MIXING WILL ALLOW POLLUTANTS SUCH AS
  WOOD SMOKE AND INDUSTRIAL EMISSIONS TO ACCUMULATE AND REDUCE
  AIR QUALITY.
* THE MOST LIKELY PLACES TO EXPERIENCE REDUCED AIR QUALITY ARE
  ALONG AND WEST OF THE I-5 CORRIDOR.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
AN AIR STAGNATION ADVISORY IS ISSUED WHEN LOCALLY ESTABLISHED
CRITICAL VALUES OF TRANSPORT WINDS...MIXING HEIGHT...AND
VENTILATION ARE EXPECTED TO PERSIST FOR AT LEAST 72 HOURS. CHECK
WITH YOUR LOCAL AIR QUALITY AGENCY FOR POSSIBLE RESTRICTIONS IN
YOUR AREA.
$$

WIND ADVISORY
Issue Date: 436 AM PST SAT DEC 26 2009
Expiration: 400 PM PST SAT DEC 26 2009

...AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST THIS
MORNING...
...WIND ADVISORY REMAINS IN EFFECT UNTIL 4 PM PST THIS
AFTERNOON...
AN AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST THIS
MORNING. A WIND ADVISORY REMAINS IN EFFECT UNTIL 4 PM PST THIS
AFTERNOON.
* EAST WINDS OF 25 TO 35 MPH WITH GUSTS TO NEAR 50 MPH WILL
CONTINUE MAINLY EAST OF STATE ROUTES 167 AND 161. THE WINDS WILL
DIMINISH IN THE AFTERNOON.
* AREAS MOST PRONE TO STRONG EAST WINDS ARE RENTON...KENT...
AUBURN...AND SUMNER.
* THOSE...ESPECIALLY WITH HIGH PROFILE VEHICLES...PLANNING TRAVEL
ON STATE ROUTES 161 AND 167 SHOULD BE PREPARED FOR STRONG CROSS
WINDS.
* A STRONG LOW LEVEL INVERSION WILL PREVENT MUCH MIXING FROM
OCCURRING OVER THOSE AREAS NOT PRONE TO STRONG EAST WINDS.
THIS WILL ALLOW POLLUTANTS LIKE WOOD SMOKE AND INDUSTRIAL
EMISSIONS TO ACCUMULATE AND REDUCE AIR QUALITY.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A WIND ADVISORY IS ISSUED WHEN SUSTAINED WINDS OF 30 TO 39 MPH OR
GUSTS OF 45 TO 57 MPH ARE LIKELY. WINDS THIS STRONG CAN SNAP
SMALL TREE BRANCHES...TOPPLE SMALL OR SHALLOW-ROOTED TREES...AND
CAUSE LOCAL POWER OUTAGES.
AN AIR STAGNATION ADVISORY IS ISSUED WHEN LOCALLY ESTABLISHED
CRITICAL VALUES OF TRANSPORT WINDS...MIXING HEIGHT...AND
VENTILATION ARE EXPECTED TO PERSIST FOR AT LEAST 72 HOURS. CHECK
WITH YOUR LOCAL AIR QUALITY AGENCY FOR POSSIBLE RESTRICTIONS IN
YOUR AREA.
$$