* WHAT...For the Dense Fog Advisory, visibility less than one mile
in dense fog. For the Air Stagnation Advisory in valleys, an
extended period of stagnant air, with light winds and little
vertical mixing. This is due to an inversion near the surface that
will continue to trap pollutants.
* WHERE...Lower Treasure Valley in Idaho and Oregon.
* WHEN...For the Dense Fog Advisory, until 2 PM MST this afternoon.
For the Air Stagnation Advisory, until 9 PM MST Friday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous.
* WHAT...An extended period of stagnant air, with light winds and
little vertical mixing. This is due to an inversion near the
surface that will continue to trap pollutants in valleys.
* WHERE...Portions of south central, southwest, and west central
Idaho and northeast and southeast Oregon.
* WHEN...Until 9 PM MST /8 PM PST/ Friday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...For the Dense Fog Advisory, visibility less than one mile
in dense fog. For the Air Stagnation Advisory in valleys, an
extended period of stagnant air, with light winds and little
vertical mixing. This is due to an inversion near the surface that
will continue to trap pollutants.
* WHERE...Lower Treasure Valley in Idaho and Oregon.
* WHEN...For the Dense Fog Advisory, until 2 PM MST this afternoon.
For the Air Stagnation Advisory, until 9 PM MST Friday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous.
* WHAT...Temperatures will continue warming this morning, allowing
the cold weather advisory to expire. A ridge of high pressure will
lead to a strong inversion and stagnant air conditions near the
surface that will continue to trap pollutants. This could worsen
air quality over time.
* WHERE...For the Air Stagnation Advisory, the Rogue, Applegate and
Sams valleys in Jackson County, including Medford, Talent,
Phoenix, Eagle Point, Central Point, Jacksonville, Applegate and
Shady Cove.
* WHEN...Until 4 PM PST Wednesday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...A ridge of high pressure will lead to a strong inversion
and stagnant air conditions near the surface that will continue to
trap pollutants. This could worsen air quality over time.
* WHERE...Valley locations across southern Oregon. West of the
Cascades, this includes the Umpqua, Illinois, Applegate, and Rogue
valleys, including Grants Pass, Sunny Valley, Galice, Murphy,
Selma, Cave Junction and O'Briend. East of the Cascades, this
includes Klamath Falls, Sprague River, Chiloquin, Chemult, Silver
Lake, Paisley, and surrounding areas.
* WHEN...Until 4 PM PST Wednesday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...Temperatures of 33 to 36 will result in frost formation.
* WHERE...South Central Oregon Coast, including all coastal areas
from Port Orford north to around Reedsport as well as the Coquille
Valley.
* WHEN...Until 9 AM PST this morning.
* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive
outdoor plants may be killed if left uncovered.
* ADDITIONAL DETAILS...A few of the typically colder locations could
fall to freezing.
* WHAT...Temperatures will continue warming this morning, allowing
the cold weather advisory to expire. A ridge of high pressure will
lead to a strong inversion and stagnant air conditions near the
surface that will continue to trap pollutants. This could worsen
air quality over time.
* WHERE...For the Air Stagnation Advisory, the Rogue, Applegate and
Sams valleys in Jackson County, including Medford, Talent,
Phoenix, Eagle Point, Central Point, Jacksonville, Applegate and
Shady Cove.
* WHEN...Until 4 PM PST Wednesday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...Visibility less than one half mile locally less than one
quarter mile.
* WHERE...Central Oregon, Foothills of the Southern Blue Mountains
of Oregon, and North Central Oregon.
* WHEN...Until 11 AM PST this morning.
* IMPACTS...Low visibility will make driving conditions hazardous.
Slick road conditions may also develop especially on bridges and
overpasses.
* WHAT...For the Air Stagnation Advisory, Light winds and limited
air movement will lead to a period of stagnant air conditions.
This scenario could result in the build up of air pollutants over
time. For the Dense Fog Advisory, visibility one quarter mile or
less in dense fog.
* WHERE...Central Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Thursday.
For the Dense Fog Advisory, until 11 AM PST this morning.
* IMPACTS...Deteriorating air quality may cause issues for people
with respiratory problems. Low visibility could make driving
conditions hazardous.
* WHAT...Light winds and limited air movement will lead to a period
of stagnant air conditions. This scenario could result in the
build up of air pollutants over time.
* WHERE...Foothills of the Northern and Central Oregon Cascades,
North and Central Coast Range Valleys of Oregon, Lower Columbia
River and Cowlitz River Valleys, Tualatin Valley, Outer Southeast
Portland Metro, Willapa and Wahkiakum Lowlands, North Clark County
Lowlands, and South Washington Cascade Foothills.
* WHEN...Until 4 AM PST Thursday.
* IMPACTS...Deteriorating air quality may cause issues for people
with respiratory problems.
* WHAT...For the Dense Fog Advisory, visibility one quarter mile or
less in dense fog. For the Air Stagnation Advisory, Light winds
and limited air movement will lead to a period of stagnant air
conditions. This scenario could result in the build up of air
pollutants over time.
* WHERE...South Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Thursday.
For the Dense Fog Advisory, until 11 AM PST this morning.
* IMPACTS...Deteriorating air quality may cause issues for people
with respiratory problems. Low visibility could make driving
conditions hazardous.
* WHAT...For the Dense Fog Advisory, visibility one quarter mile or
less in dense fog. For the Air Stagnation Advisory, Light winds
and limited air movement will lead to a period of stagnant air
conditions. This scenario could result in the build up of air
pollutants over time.
* WHERE...South Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Thursday.
For the Dense Fog Advisory, until 11 AM PST this morning.
* IMPACTS...Deteriorating air quality may cause issues for people
with respiratory problems. Low visibility could make driving
conditions hazardous.
* WHAT...For the Air Stagnation Advisory, Light winds and limited
air movement will lead to a period of stagnant air conditions.
This scenario could result in the build up of air pollutants over
time. For the Dense Fog Advisory, visibility one quarter mile or
less in dense fog.
* WHERE...Central Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Thursday.
For the Dense Fog Advisory, until 11 AM PST this morning.
* IMPACTS...Deteriorating air quality may cause issues for people
with respiratory problems. Low visibility could make driving
conditions hazardous.
Dense freezing fog has formed along interstate 84 east of
Pendleton on Cabbage Hill with visibilities less than one quarter
mile. motorists are urged to use caution when traveling this
stretch of interstate tonight and be alert for patches of ice on
the roadways.
Areas of dense fog will impact mainly parts of Clackamas County
in the Portland metro area overnight into early Monday morning.
This includes Milwaukie, Lake Oswego, Oregon City, and Happy
Valley. Visibility will be reduced to one quarter mile or less at
times, and low visibility could make driving conditions hazardous
in these locations. Locations within the City of Portland and
Multnomah County will mostly remain clear due to east winds out of
the Columbia River Gorge. If you encounter dense fog while
driving, slow down and leave plenty of distance ahead of you.
Pedestrians and cyclists should wear bright or reflective clothing
to increase the chances of being seen by others in poor
visibility conditions.
* WHAT...For the Cold Weather Advisory, very cold temperatures as
low as 18 degrees expected.
A ridge of high pressure will lead to a strong inversion and
stagnant air conditions near the surface that will continue to trap
pollutants. This could worsen air quality over time.
* WHERE...For the Cold Weather Advisory, the southern end of the
Rogue Valley including Ashland as well as the outskirts of Phoenix
and Talent; the Shady Cove area; areas east of Eagle Point and
White City on Highway 140; and portions of the Applegate Valley
including the outskirts of Ruch, Applegate, and Jacksonville Hill.
For the Air Stagnation Advisory, the Rogue, Applegate and Sams
valleys in Jackson County, including Medford, Talent, Phoenix, Eagle
Point, Central Point, Jacksonville, Applegate and Shady Cove.
* WHEN...For the Cold Weather Advisory, from 2 AM to 8 AM PST Monday.
For the Air Stagnation Advisory, until 4 PM PST Wednesday.
* IMPACTS...Frostbite and hypothermia will occur if unprotected skin
is exposed to these temperatures, especially for longer periods of
time.
Poor air quality may cause issues for people with respiratory
problems.
* WHAT...A ridge of high pressure will lead to a strong inversion
and stagnant air conditions near the surface that will continue to
trap pollutants. This could worsen air quality over time.
* WHERE...Valley locations across southern Oregon. West of the
Cascades, this includes the Umpqua, Illinois, Applegate, and Rogue
valleys, including Grants Pass, Sunny Valley, Galice, Murphy,
Selma, Cave Junction and O'Briend. East of the Cascades, this
includes Klamath Falls, Sprague River, Chiloquin, Chemult, Silver
Lake, Paisley, and surrounding areas.
* WHEN...Until 4 PM PST Wednesday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...Temperatures of 33 to 36 will result in frost formation.
* WHERE...South Central Oregon Coast, including all coastal areas
from Port Orford north to around Reedsport as well as the Coquille
Valley.
* WHEN...From 9 PM this evening to 9 AM PST Monday.
* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive
outdoor plants may be killed if left uncovered.
* ADDITIONAL DETAILS...A few of the typically colder locations could
fall to freezing.
* WHAT...For the Cold Weather Advisory, very cold temperatures as
low as 18 degrees expected.
A ridge of high pressure will lead to a strong inversion and
stagnant air conditions near the surface that will continue to trap
pollutants. This could worsen air quality over time.
* WHERE...For the Cold Weather Advisory, the southern end of the
Rogue Valley including Ashland as well as the outskirts of Phoenix
and Talent; the Shady Cove area; areas east of Eagle Point and
White City on Highway 140; and portions of the Applegate Valley
including the outskirts of Ruch, Applegate, and Jacksonville Hill.
For the Air Stagnation Advisory, the Rogue, Applegate and Sams
valleys in Jackson County, including Medford, Talent, Phoenix, Eagle
Point, Central Point, Jacksonville, Applegate and Shady Cove.
* WHEN...For the Cold Weather Advisory, from 2 AM to 8 AM PST Monday.
For the Air Stagnation Advisory, until 4 PM PST Wednesday.
* IMPACTS...Frostbite and hypothermia will occur if unprotected skin
is exposed to these temperatures, especially for longer periods of
time.
Poor air quality may cause issues for people with respiratory
problems.
* WHAT...Visibility less than half a mile in freezing fog with some
locally dense freezing fog with less than one quarter of a mile
visibility.
* WHERE...Central Oregon mainly in areas north of Bend, Foothills of
the Southern Blue Mountains of Oregon, and North Central Oregon.
* WHEN...Until 11 AM PST Monday.
* IMPACTS...Low visibility could make driving conditions hazardous.
The freezing fog can also cause slick conditions on roads,
especially on bridges and overpasses.
