A series of fronts brought heavy rain over several days leading to several landslides across Northwest Oregon.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PQR wrote it up.
A series of fronts brought heavy rain over several days leading to several landslides across Northwest Oregon.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Portland, OR wrote its last area forecast discussion before the first event at Feb 5, 3:59 AM PST, 1 hour 1 minute earlier.
Area Forecast Discussion
National Weather Service Portland OR
359 AM PST Sun Feb 5 2017
...UPDATED AVIATION AND MARINE SECTIONS...
.SYNOPSIS...A cold low pressure system will remain centered off the
Washington coast through Sunday into Sunday night, with a cold
frontal boundary over southwest Washington and northwest Oregon.
Several surges of moisture will ride along the front into our area
with increasing rain, heavy at times, later tonight and Sunday.
Colder air along the back edge of the front in combination with heavy
precipitation rates along the front could drive snow levels down to
near the valley floors later Sunday and Sunday night. A low out near
37N 140W will be pulled toward our area and contribute moisture to
the heavy precipitation on Sunday, then help push the front through
the area by Monday morning. The low level flow will turn onshore and
well mixed as the main low center off the Washington coast moves
through on Monday. The air mass will remain cold on Monday but snow
levels will rise to around 1000 feet or so. Another system may
approach from the southwest Tuesday bringing a chance for active
weather.
&&
.SHORT TERM...Tonight through Tuesday night...A very complex
situation still is expected to develop Sunday. A cold front
associated with the low centered off the Washington coast moved onto
the north coastal areas this evening and will stall over southwest
Washington and northwest Oregon tonight and Sunday. The models
continue to forecast that increasing moisture, an atmospheric river
if you will, will ride along the front into our area later tonight
and Sunday with increasing heavy rain that could lead to some rivers
flooding, especially from the central Oregon coastal area
northeastward toward Mount Hood, in combination with some urban
flooding. We have a Flood Watch in effect for this. But colder air
along the back edge of the frontal boundary and the heavy
precipitation rates along the front could be enough to eventually
drive snow levels close to the valley floors and to near sea level
along the coast later Sunday and Sunday night.
Unlike our typical snow situations where cold air from the Gorge is
overridden by moisture or a cold enough air mass swings onshore from
off the Pacific, this scenario where existing rain changes over to
snow due to the thermodynamics of heavy rainfall rates and
sufficiently cold air nearby occurs much less frequently, with
recent examples of 11/19/2003 near Portland and March 2012 around
Eugene. Bottom line is that we could see snow or just cold rain, but
if the precipitation turns to snow, we could see significant amounts
that have big impacts due to the high moisture content over the area.
Our models and model soundings still suggest this is possible. We
will keep the current watches in effect. This is a situation where we
might not convert our watches to warnings or advisories until the
event begins to unfold, so be sure to stay tuned and prepared,
whichever way this unfolds.
The frontal boundary moves through the forecast area by 12z Monday as
the low out near 37N 140W is pulled in along the front and moves
through our area. This will bring an end to the heavy rain, and any
valley snow that does occur Sunday afternoon and night will decrease
as well. The low level flow will turn distinctly onshore on Monday
behind this front with significant orographic snows in the mountains.
Though thicknesses fall well down into the 520s Monday, the air mass
will become well mixed which should actually lift the snow level a
bit up off the valley floors, to perhaps around 1000 feet. However, a
heavier shower might briefly drop the snow level a bit lower.
Tolleson
Remainder of discussion unchanged...There will be a lull in the
precipitation for part of Tuesday as we transition to offshore flow
as a low develops and approaches from the southwest. Models have some
disagreement on the evolution of the this system for the Tuesday
night time period. The GFS keeps the bulk of the precipitation to the
south of the area while the wetter NAM spreads precipitation across
the forecast area by Tuesday evening. The ECMWF is a good compromise
between the two at this point. Snow levels will be fairly low, near
1000 ft or so, especially in the northern zones with the cool dry
offshore flow. But moisture will be the limiting factor on how low
snow level will eventually be.
.LONG TERM...Tuesday night through Saturday. Active weather will
continue through the week as several disturbances move across the
region. An upper level trough sweeps across northern WA/Southern BC
on Wed with cool, showery weather over the area. There is potential
for a strong and wet system Wed night and Thurs with NWP models
showing a sub-tropical moisture tap. ECMWF and GFS differ widely on
the strength and position of the low with GFS much stronger and
closer to the coast. Either way, mid-week will be a wet period.
There are indications we dry out toward the end of the week as a
ridge of high pressure builds across the northeast Pacific and into
the Pacific Northwest. tw
&&
.AVIATION...A mix of MVFR and VFR CIGS continue with steady -RA
and occasional RA. Expect MVFR to become more prevalent through
the morning hours as rain rates intensify. A low will move
through the area, likely tracking between KEUG and KSLE this
evening with areas north of the track seeing -RASN and eventually
some -SN in the evening and overnight hours before switching back
to -RA after a trailing front passes through. Amounts will be
quite variable depending on when snow starts in relation to the
precipitation rates, but heaviest snow appears like it will be
north of a KTMK to KPDX line and likely spare KAST for the most
part.
KPDX AND APPROACHES...Mostly VFR in the area early this morning
but expect deteriorating conditions as rainfall rates increase
into the morning hours. Rain will begin to mix with snow
somewhere around 21Z Sun and switch to all snow around 03Z Mon.
Expect a switch back to -RASN or even straight to -RA after the
front passes through, likely before 12Z Monday. Bowen
&&
.MARINE...Winds turning to out of the west early this morning and
have decreased to 15 to 20 kt with gusts to 25 kt. Expect winds
to turn more northerly later today and decrease further. As a low
pressure system moves near and onshore around North Bend, OR,
winds south of about Waldport will turn back to out of the south
and pick up with gusts to about 30 kt possible this afternoon and
evening. Seas will hover around 10 ft into the morning hours and
then generally decrease. But the same area which sees increased
winds later today will likely also see seas increase back to
around 10 ft for a bit. Have adjusted Small Craft Advisories for
Winds and Seas to reflect this trend.
There will be a few periods of borderline small craft advisory
winds and seas for the first half of the work week, but main
focus will be increasing seas and winds Wed night through Thu
night. Models continue to waffle with seas, now keeping them
below 20 ft instead of near 30 ft as previous runs showed. Also
seeing the possibility of storm winds with this system, but at
this point gales appear to be the most likely scenario. Again,
expect plenty of changes to the forecast between now and then.
Bowen
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...Winter Storm Warning until 6 PM PST Monday for Northern Oregon
Cascade Foothills-Northern Oregon Cascades-Upper Hood
River Valley.
Winter Weather Advisory from 10 AM this morning to 6 AM PST
Monday for Central Willamette Valley-Greater Portland
Metro Area-Western Columbia River Gorge.
Winter Weather Advisory until 6 PM PST Monday for Cascades in
Lane County-Central Columbia River Gorge.
Flood Watch from 8 AM PST this morning through Monday morning
for Cascade Foothills in Lane County-Central Coast Range
of Western Oregon-Central Oregon Coast-Central Willamette
Valley-Coast Range of Northwest Oregon-Greater Portland
Metro Area-North Oregon Coast-Northern Oregon Cascade
Foothills-South Willamette Valley.
Winter Storm Warning from 10 AM this morning to 6 AM PST Monday
for Lower Columbia-North Oregon Coast.
Winter Weather Advisory from 10 AM this morning to 1 AM PST
Monday for Central Oregon Coast.
Winter Storm Warning from 8 AM this morning to 6 AM PST Monday
for Central Coast Range of Western Oregon-Coast Range of
Northwest Oregon.
WA...Winter Storm Warning until 6 PM PST Monday for South Washington
Cascade Foothills-South Washington Cascades.
Winter Weather Advisory from 10 AM this morning to 6 AM PST
Monday for Greater Vancouver Area-Western Columbia River
Gorge.
Winter Weather Advisory until 6 PM PST Monday for Central
Columbia River Gorge.
Flood Watch from 8 AM PST this morning through Monday morning
for Greater Vancouver Area.
Winter Storm Warning from 10 AM this morning to 6 AM PST Monday
for I-5 Corridor in Cowlitz County.
Winter Weather Advisory from 10 AM this morning to 1 AM PST
Monday for South Washington Coast.
Winter Storm Warning from 8 AM this morning to 6 AM PST Monday
for Willapa Hills.
PZ...Small Craft Advisory for winds until 8 AM PST this morning for
Coastal Waters from Cape Shoalwater WA to Florence OR out
60 nm.
Small Craft Advisory for hazardous seas until 10 AM PST this
morning for Coastal Waters from Cape Shoalwater WA to
Cascade Head OR out 60 nm.
Small Craft Advisory for winds from 2 PM this afternoon to
midnight PST tonight for Coastal Waters from Cascade Head
OR to Florence OR out 60 nm.
Small Craft Advisory for hazardous seas until 4 AM PST Monday
for Coastal Waters from Cascade Head OR to Florence OR out
60 nm.
Small Craft Advisory for Rough Columbia River Bar from 8 AM
this morning to 3 PM PST this afternoon.
Small Craft Advisory for Rough Columbia River Bar from 10 PM
this evening to 2 AM PST Monday.
&&
Interact with us via social media:
www.facebook.com/NWSPortland
www.twitter.com/NWSPortland
This discussion is for Northwest Oregon and Southwest Washington
from the Cascade crest to 60 nautical miles offshore. The area is
commonly referred to as the forecast area.The national radar mosaic for the moment the first event began.
4 heavy rain. Local standard time, as filed.
Broadcast Media reported a landslide closed Highway 224 near Tong Road in Damascus in both directions following a weekend of heavy rain.
Multnomah County Sheriff's Office reported that heavy rain caused a landslide on the Historic Columbia River Highway near the Stark Street Bridge.
Multnomah County Sheriff's Office reported flooding and a sinkhole near the 31700 block of SE Pipeline Rd.
Portland Bureau of Transportation reported a landslide closed 1 lane on highway 26 near the Oregon Zoo, and another landslide near Skyline Blvd.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2017Every state in 2017This day in weather historyWarnings in Oregon, February 2017
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 682840, 682841, 682842, 682843.