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Air Stagnation Advisory


URGENT - WEATHER MESSAGE
National Weather Service Seattle WA
1249 PM PST Tue Dec 12 2017

WAZ503-504-506-507-509>511-514-555-556-558-559-132000-
/O.CON.KSEW.AS.Y.0001.000000T0000Z-171214T2200Z/
Western Whatcom County-Southwest Interior-Western Skagit County-
Everett and Vicinity-Tacoma Area-Admiralty Inlet Area-
Hood Canal Area-Eastern Strait of Juan de Fuca-
East Puget Sound Lowlands-Bellevue and Vicinity-
Seattle and Vicinity-Bremerton and Vicinity-
1249 PM PST Tue Dec 12 2017

...AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL 2 PM PST
THURSDAY...

* AIR QUALITY...Dry conditions, light winds and poor mixing has
  lead to stagnant conditions in the interior lowlands. Stagnant
  conditions will trap pollutants near the surface which will
  lead to deteriorating air quality.

* TIMING...Through Thursday afternoon.

* MAIN IMPACT...Deteriorating air quality may affect people with
  respiratory issues. Check with your local clean air agencies
  for possible burn bans.

nwcleanairwa.gov  www.orcaa.org  www.pscleanair.org
www.swcleanair.org  www.ecy.wa.gov

PRECAUTIONARY/PREPAREDNESS ACTIONS...

An Air Stagnation Advisory indicates that due to limited movement
of an air mass across the advisory area...pollution will increase
to dangerous levels. Persons with respiratory illness should
follow their physicians advice for dealing with high levels of
air pollution.

&&

$$

www.weather.gov/seattle

URGENT - WEATHER MESSAGE...CORRECTED
National Weather Service Portland OR
358 PM PST Tue Dec 12 2017

...STAGNANT AIR CONDITIONS EXPECTED INTO THURSDAY...

...FREEZING FOG EXPECTED TO DEVELOP OVERNIGHT IN THE SOUTHERN
WILLAMETTE VALLEY...

ORZ005-WAZ022-132015-
/O.CON.KPQR.AS.Y.0002.000000T0000Z-171214T2200Z/
Lower Columbia-I-5 Corridor in Cowlitz County-
Including the cities of St. Helens, Clatskanie, Longview, Kelso,
and Castle Rock
358 PM PST Tue Dec 12 2017

...AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL 2 PM PST
THURSDAY...

* AIR QUALITY...Air quality may deteriorate due to an extended
  period of stagnant air conditions.

* TIMING...through Thursday afternoon.

* LOCATIONS...The Lower Columbia and I-5 Corridor in Cowlitz
  County

* IMPACTS...Limited ventilation may result in deteriorating air
  quality continuing this week.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

An Air Stagnation Advisory indicates that due to limited movement
of an air mass across the advisory area, pollution will increase
to dangerous levels. Persons with respiratory illness should
follow their physicians advice for dealing with high levels of
air pollution.

&&

$$

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
1248 PM PST Tue Dec 12 2017

...AIR STAGNATION ADVISORY EXTENDED THROUGH FRIDAY MORNING...

Our stagnant weather pattern is not expected to change until the
arrival of a weak frontal system on Friday. Until then, a strong
temperature inversion will remain over Washington and Idaho.
Winds will also be weak heightening the potential for the build
up of air pollution.

IDC009-017-021-035-049-055-057-061-069-079-WAC001-003-007-017-019-
023-025-043-047-051-063-065-075-132000-
/O.CON.KOTX.AS.Y.0003.000000T0000Z-171215T1800Z/
Benewah-Bonner-Boundary-Clearwater-Idaho-Kootenai-Latah-Lewis-
Nez Perce-Shoshone-Adams-Asotin-Chelan-Douglas-Ferry-Garfield-
Grant-Lincoln-Okanogan-Pend Oreille-Spokane-Stevens-Whitman-
1248 PM PST Tue Dec 12 2017 /148 PM MST Tue Dec 12 2017/

...AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
/11 AM MST/ FRIDAY...

* Air Quality...Pollutants may increase this week. Regional air
  quality sensors range from good to moderate. However, light
  winds and a strong inversion will increase the potential for
  the build up of air pollution and deteriorating air quality.

* Impacts...Persons with respiratory issues should follow the
  advice of their physician on how to deal with poor air
  quality. Outdoor burning may be limited, so please consult
  with your local burn agencies for updated burn restrictions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

An Air Stagnation Advisory indicates that due to limited movement
of an air mass across the advisory area. Pollution may increase
to unhealthy levels. Persons with respiratory illness should
follow their physicians advice for dealing with high levels of
air pollution.

&&

$$

URGENT - WEATHER MESSAGE
National Weather Service Pendleton OR
1147 AM PST Tue Dec 12 2017

...STAGNANT AIR CONDITIONS CONTINUE INTO FRIDAY...

...AREAS OF DENSE FREEZING FOG FOR THE FOOTHILLS OF THE SOUTHERN
BLUE MOUNTAINS AND PORTIONS OF NORTH CENTRAL AND CENTRAL OREGON
UNTIL NOON WEDNESDAY...

.An upper level ridge will persist over the Pacific Northwest.
This ridge will cause air movement to be limited over large
portions of the region. Areas of freezing fog will be possible
and the air quality will become unhealthy at times.

WAZ024-026>029-520-521-130700-
/O.CON.KPDT.AS.Y.0003.000000T0000Z-171215T1800Z/
Eastern Columbia River Gorge of Washington-Kittitas Valley-
Yakima Valley-Lower Columbia Basin of Washington-
Foothills of the Blue Mountains of Washington-
East Slopes of the Washington Cascades-Simcoe Highlands-
including the cities of White Salmon, Ellensburg, Thorp, Naches,
Sunnyside, Toppenish, Yakima, Connell, Prosser, Tri-Cities,
Dayton, Waitsburg, Walla Walla, Appleton, Cle Elum, Cliffdell,
Goldendale, and Bickleton
1147 AM PST Tue Dec 12 2017

...AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL 10 AM PST
FRIDAY...

* AIR QUALITY...Moderate to unhealthy at times.

* TIMING...Stagnant air to persist for several more days.

* IMPACTS...Persons with respiratory issues should follow the
  advice of their physician on how to deal with poor air
  quality. Also outdoor burning may be limited, so please
  consult with your local burn agencies.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

An Air Stagnation Advisory indicates that due to limited movement
of an air mass across the advisory area...pollution has the
potential to increase to dangerous levels. Persons with
respiratory illness should follow their physicians advice for
dealing with high levels of air pollution.

During periods of stagnant air...state air quality agencies
highly recommend that no outdoor burning occur and that
residential wood burning devices be limited as much as possible.
According to state air quality agencies...prolonged periods of
stagnant air can hold pollutants close to the ground...where
people live and breathe. Check with your local burn agency for
any current restrictions in your area.

&&

$$

U.S. Dept. of Commerce
NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
E-mail: w-nws.webmaster@noaa.gov
Page last modified: June 2, 2009
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