Dense freezing fog has formed again along Interstate 84 east of
Pendleton, on Cabbage Hill. Visibilities of less than one quarter
mile were occurring in this area. Motorists are urged to use
caution when traveling on this stretch of interstate through the
morning hours due to low visibilities and patches of ice.
* 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 5 PM MST /4 PM PST/ Saturday.
* IMPACTS...Poor 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 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...Treasure Valley Zones and the Weiser Basin.
* WHEN...For the Dense Fog Advisory, until 11 AM MST Saturday. For
the Air Stagnation Advisory, until 5 PM MST Saturday.
* IMPACTS...Low visibility could make driving conditions hazardous.
Poor air quality may cause issues for people with respiratory
problems.
* ADDITIONAL DETAILS...Fog could produce patchy black ice and slick
roads.
* WHAT...For the Dense Fog Advisory, visibility one quarter mile or
less 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...Treasure Valley Zones and the Weiser Basin.
* WHEN...For the Dense Fog Advisory, until 11 AM MST Saturday. For
the Air Stagnation Advisory, until 5 PM MST Saturday.
* IMPACTS...Low visibility could make driving conditions hazardous.
Poor air quality may cause issues for people with respiratory
problems.
* ADDITIONAL DETAILS...Fog could produce patchy black ice and slick
roads.
* WHAT...Visibility one quarter of a mile or less in freezing fog.
* WHERE...John Day Basin.
* WHEN...Until 11 AM PST Friday.
* IMPACTS...Low visibility and slick roads could make driving
conditions hazardous.
* WHAT...Visibility one quarter of a mile or less in freezing fog.
* WHERE...Central Oregon.
* WHEN...Until 11 AM PST Friday.
* IMPACTS...Low visibility and slick roads could make driving
conditions hazardous.
* WHAT...Visibility one quarter of a mile or less in freezing fog.
* WHERE...Foothills of the Southern Blue Mountains of Oregon and
North Central Oregon.
* WHEN...Until 11 AM PST Friday.
* IMPACTS...Low visibility and slick roads 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, Central Willamette Valley,
Tualatin Valley, Outer Southeast Portland Metro, Willapa and
Wahkiakum Lowlands, North Clark County Lowlands, and South
Washington Cascade Foothills.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* 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 frequently below one
quarter mile in dense fog and areas of freezing fog.
* WHERE...South Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Saturday.
For the Dense Fog Advisory, until 11 AM PST Friday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous.
* ADDITIONAL DETAILS...Fog will reform and increase across the south
Willamette Valley this evening. Overall, temperatures will hold at
or just above freezing overnight. But, a few spots will drop back
below freezing. As such, motorists should be prepared for
potentially icy or slick spots, especially on less-traveled rural
roadways and bridges.
* 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 frequently below one
quarter mile in dense fog and areas of freezing fog.
* WHERE...South Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Saturday.
For the Dense Fog Advisory, until 11 AM PST Friday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous.
* ADDITIONAL DETAILS...Fog will reform and increase across the south
Willamette Valley this evening. Overall, temperatures will hold at
or just above freezing overnight. But, a few spots will drop back
below freezing. As such, motorists should be prepared for
potentially icy or slick spots, especially on less-traveled rural
roadways and bridges.
* 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. East of the Cascades, this includes Klamath Falls,
Sprague River, Chiloquin, Chemult, Silver Lake, Paisley, and
surrounding areas.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Low visibility could make driving conditions hazardous.
Watch for icy spots on roads. Poor air quality may cause issues
for people with respiratory problems.
Dense freezing fog will continue along Interstate 84 east of
Pendleton towards Cabbage Hill, with visibilities less than one
quarter mile. Motorists are urged to use caution when traveling
this stretch of interstate this afternoon tonight and be alert for
patches of ice on the roadway.
* 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...South Willamette Valley.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* 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, Central Willamette Valley,
Tualatin Valley, Outer Southeast Portland Metro, Willapa and
Wahkiakum Lowlands, North Clark County Lowlands, and South
Washington Cascade Foothills.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Deteriorating air quality may cause issues for people
with respiratory problems.
If you are located in this coastal area, move inland
to higher ground.
Tsunami warnings mean that a tsunami with significant
inundation is possible or is already occurring. Tsunamis are
a series of waves dangerous many hours after initial arrival
time. The first wave may not be the largest.
At 1044 AM Pacific Standard Time on December 5 an earthquake with
preliminary magnitude 7.3 occurred 45 miles southwest of
Eureka California.
Estimated tsunami start times for selected sites are;
Fort Bragg California 1110 AM. PST. December 5.
Crescent City California 1120 AM. PST. December 5.
Port Orford Oregon 1120 AM. PST. December 5.
Brookings Oregon 1125 AM. PST. December 5.
Charleston Oregon 1140 AM. PST. December 5.
San Francisco California 1210 PM. PST. December 5.
The tsunami warning will remain in effect until further notice.
Refer to the internet site tsunami.gov for more information.
* WHAT...Visibility less than one quarter mile in freezing fog.
Although there will be some improvement in the visibility this
afternoon, dense freezing fog will return tonight.
* WHERE...Foothills of the Southern Blue Mountains of Oregon and
North Central Oregon.
* WHEN...Until 11 AM PST Friday.
* IMPACTS...Low visibility and slick roads could make driving
conditions hazardous.
* ADDITIONAL DETAILS...Periods of light snow flurries or light
freezing drizzle may be observed as well.
* 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 5 PM MST /4 PM PST/ Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...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. For the Dense Fog Advisory,
visibility one quarter mile or less in dense fog.
* WHERE...Treasure Valley Zones.
* WHEN...For the Air Stagnation Advisory, until 5 PM MST Saturday.
For the Dense Fog Advisory, until 2 PM MST Friday.
* IMPACTS...Low visibility could make driving conditions hazardous
especially for the morning commute. Poor air quality may cause
issues for people with respiratory problems. Low visibility could
make driving conditions hazardous.
* ADDITIONAL DETAILS...Fog could produce patchy black ice and slick
roads.
* WHAT...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. For the Dense Fog Advisory,
visibility one quarter mile or less in dense fog.
* WHERE...Treasure Valley Zones.
* WHEN...For the Air Stagnation Advisory, until 5 PM MST Saturday.
For the Dense Fog Advisory, until 2 PM MST Friday.
* IMPACTS...Low visibility could make driving conditions hazardous
especially for the morning commute. Poor air quality may cause
issues for people with respiratory problems. Low visibility could
make driving conditions hazardous.
* ADDITIONAL DETAILS...Fog could produce patchy black ice and slick
roads.
* WHAT...Valley locations may see poor air quality. This is due to
an inversion and stagnant air conditions near the surface that
will continue to trap pollutants.
* WHERE...Valleys in Douglas, Josephine, and Jackson County. This
includes the Umpqua, Illinois, Applegate, and Rogue valleys.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
