* 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...South winds 25 to 35 mph with gusts up to 50 mph expected
for Ladd and Pyles Canyons.
* WHERE...Grande Ronde Valley.
* WHEN...From 6 AM to 4 PM PST Saturday.
* IMPACTS...Gusty winds will blow around unsecured objects. Tree
limbs could be blown down and a few power outages may result.
* 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.
...LIGHT FREEZING RAIN, MOUNTAIN SNOW EXPECTED THIS WEEKEND...
.A system moving across our region will bring areas of rain and some
light freezing rain to portions of the lower slopes of the eastern
Washington Cascades as well as the Kittitas Valley on Saturday. Then
on Sunday, areas of moderate snowfall will begin to fall across the
Washington Cascades as well as the northern Blue Mountains of both
Washington and Oregon.
* WHAT...Snow expected. Total snow accumulations of 4-6 inches.
Winds gusting as high as 40 mph.
* WHERE...In Oregon, Northern Blue Mountains of Oregon. In
Washington, Northwest Blue Mountains.
* WHEN...From 4 PM Saturday to 4 PM PST Sunday.
* IMPACTS...Travel could be difficult due to periods of moderate to
heavy snow.
* 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 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...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...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...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.
* WHAT...Visibility one quarter of a mile or less in freezing fog.
* WHERE...John Day Basin.
* WHEN...Until 11 AM PST this morning.
* 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 this morning.
* IMPACTS...Low visibility and slick roads could make driving
conditions hazardous.
