* 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 and the Weiser Basin.
* WHEN...For the Air Stagnation Advisory, until 5 PM MST Saturday.
For the Dense Fog Advisory, until 11 AM MST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous.
* ADDITIONAL DETAILS...Fog and snow flurries 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 and the Weiser Basin.
* WHEN...For the Air Stagnation Advisory, until 5 PM MST Saturday.
For the Dense Fog Advisory, until 11 AM MST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous.
* ADDITIONAL DETAILS...Fog and snow flurries could produce patchy
black ice and slick roads.
* WHAT...Snow and freezing rain expected. Total snow accumulations
up to one inch and ice accumulations less than one tenth of an
inch.
* WHERE...Lower Treasure Valley Zones, and northern Malheur County
including Highways 20 and 26.
* WHEN...From 5 PM MST /4 PM PST/ Saturday to 5 AM MST /4 AM PST/
Sunday.
* IMPACTS...Roads, and especially bridges and overpasses, will
likely become slick and hazardous. Plan on slippery road
conditions.
* WHAT...Flooding caused by excessive rainfall is possible.
* WHERE...A portion of northwest Washington, including the following
county, Mason.
* WHEN...From Saturday afternoon through Sunday evening.
* IMPACTS...Excessive runoff may result in flooding of rivers,
creeks, streams, and other low-lying and flood-prone locations.
* ADDITIONAL DETAILS...
- A stronger storm system will bring 2 to 3 inches of rain,
possibly more to the Olympic mountains Friday night into
Sunday morning. With snow levels above 7000 feet for the bulk
of the precipitation, most of that will be rain and that
could be enough to drive the Skokomish River above flood
stage. The current river forecast has it cresting just below
flood stage.
- http://www.weather.gov/safety/flood
* 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...Inner Vancouver Metro.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Deteriorating 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.
* 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.
* WHAT...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...Until 4 AM PST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems.
* WHAT...Visibility less than a quarter mile in freezing fog.
* WHERE...North Central Oregon.
* WHEN...Until 11 AM PST Saturday.
* IMPACTS...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...Inner Vancouver Metro.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Deteriorating 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.
* 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.
* 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...South Willamette Valley.
* WHEN...For the Dense Fog Advisory, until 1 PM PST this afternoon.
For the Air Stagnation Advisory, until 4 AM PST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous. With temperatures at or just below freezing, fog
droplets may freeze on contact with surfaces, with slick spots on
roadways possible early Friday morning.
* 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 one quarter mile or
less in dense fog.
* WHERE...South Willamette Valley.
* WHEN...For the Dense Fog Advisory, until 1 PM PST this afternoon.
For the Air Stagnation Advisory, until 4 AM PST Saturday.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous. With temperatures at or just below freezing, fog
droplets may freeze on contact with surfaces, with slick spots on
roadways possible early Friday morning.
* 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.
Dense freezing fog has formed again along Interstate 84 east of
Pendleton, on Cabbage Hill. In the LaGrande area, patchy dense
freezing fog was also occurring, along with very cold
temperatures. Visibilities of less than one half mile were
occurring in these areas.
Motorists are urged to use caution when traveling on Interstate
84 east of Pendleton through the morning hours due to low
visibilities and patches of ice.
* 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.
* 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...Inner Vancouver Metro.
* WHEN...Until 4 AM PST Saturday.
* IMPACTS...Deteriorating 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.
* 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...South Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Saturday.
For the Dense Fog Advisory, until 11 AM PST this morning.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous. With temperatures at or just below freezing, fog
droplets may freeze on contact with surfaces, with slick spots on
roadways possible early Friday morning.
* 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...South Willamette Valley.
* WHEN...For the Air Stagnation Advisory, until 4 AM PST Saturday.
For the Dense Fog Advisory, until 11 AM PST this morning.
* IMPACTS...Poor air quality may cause issues for people with
respiratory problems. Low visibility could make driving conditions
hazardous. With temperatures at or just below freezing, fog
droplets may freeze on contact with surfaces, with slick spots on
roadways possible early Friday morning.