Flood Watch issued December 8 at 3:35PM PST until December 12 at 4:00AM PST by NWS Portland OR
* WHAT...River and urban flooding caused by excessive rainfall is
possible. Landslides possible in areas of steep terrain, and
debris flows possible over recently burned areas.
* WHERE...Counties in Oregon: Benton, Clackamas, Clatsop, Columbia,
Hood River, Lane, Lincoln, Linn, Marion, Multnomah, Polk,
Tillamook, Washington, and Yamhill. Counties in Washington: Clark,
Cowlitz, Pacific, Skamania, and Wahkiakum.
* WHEN...Through late Thursday night.
* IMPACTS...Excessive runoff may result in flooding of rivers,
creeks, streams, and other low-lying and flood-prone locations.
Landslides and debris flows are possible during this flood event.
People, structures, and roads located below steep slopes, in
canyons, and near the mouths of canyons may be at serious risk
from rapidly moving landslides.
* ADDITIONAL DETAILS...
- A prolonged atmospheric river is expected to bring periods of
heavy rain to northwest Oregon and southwest Washington
Monday through Wednesday, with periods of lighter rain
continuing Thursday into Friday. This weather system will
result in an increased risk for flooding. Additional forecast
rain amounts from 4 PM Monday through 4 AM Thursday range
from 2.5 to 5 inches in the Cowlitz Valley, Lower Columbia,
Portland/Vancouver metro and northern Willamette Valley, 1.5
to 2.5 inches in the central Willamette Valley, and 0.75-1.5
inches in the southern Willamette Valley. Forecast rain
amounts reach 6 to 12 inches in the Cascades, Cascade
foothills, Coast Range and the coast, except 1.5-3.5 inches
from Florence to Newport and in areas of higher terrain in
Lane County. Rivers draining the coastal mountains and
several Willamette Tributaries have a 50 to 70% chance of
reaching minor flood stage or higher. The Pudding River at
Aurora and Johnson Creek at Sycamore have an 80% chance of
reaching minor flood stage or higher. Chances for flooding
along the Willamette mainstem remains low at 5-15%. Urban
flooding is possible and water on roadways will increase the
risk of hydroplaning and car accidents. Landslides in areas
of steep terrain will be possible due to saturated soils, as
well as debris flows over recently burned areas.
- http://www.weather.gov/safety/flood
You should monitor later forecasts and be alert for possible Flood
Warnings. Those living in areas prone to flooding should be prepared
to take action should flooding develop.
Varoitus voimassa ti klo 1:35 - pe klo 14:00
