A cold front moving across the area brought heavy snow to the South Washington Cascades. Snow along the front and post frontal showers brought 12-20 inches of snow to multiple locations around 4000 feet and higher.
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 cold front moving across the area brought heavy snow to the South Washington Cascades. Snow along the front and post frontal showers brought 12-20 inches of snow to multiple locations around 4000 feet and higher.
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 Nov 24, 2:38 AM PST, 2 hours 22 minutes earlier.
Area Forecast Discussion
National Weather Service Portland Oregon
238 AM PST Thu Nov 24 2016
.SYNOPSIS...A strong frontal boundary will move into Southwest
Washington and far Northwest Oregon this morning then become nearly
stationary. A secondary low pressure area develops offshore along the
front this afternoon, reaching the North Washington coast Thursday
night. The frontal boundary weakens late Thursday night and Friday
morning with the main energy over Southwest Oregon. A cold upper
trough settles over the forecast area this weekend. The general
progressive pattern continues next week.
&&
.SHORT TERM...Today through Saturday...Complicated weather pattern
shaping up during the next 36-48 hours with below normal confidence
in some details due to continued model differences. Water vapor
satellite imagery early this morning shows an impressive shortwave
trough encompassing much of the Gulf of Alaska. More impressive is
the convective activity over the coastal waters and the South
Washington and North Oregon coast associated with a frontal boundary.
KLGX Doppler radar shows the impressive line extending from near
Raymond to about KTMK. Lightning detection showed up to 125 cloud to
ground strikes within this line from 08Z to 09Z.
A strong jet on the backside of the trough is beginning to result in
the shortwave trough digging. This will result in the approaching
front to become more oriented from southwest to northeast as it drops
southeastward across the area late tonight and Thursday. Biggest
forecast question today will be QPF. Models differ on location of the
QPF core within the baroclinic zone. The 06Z NAM has the front
stalling across SW Washington and far NW Oregon this afternoon, while
the ECMWF is a little more southeast, somewhat similar to the 00Z
GFS. However, the 06Z GFS is trending toward the 06Z NAM solution.
Another forecast issue will be coastal wind. 06Z NAM does show 70 kt
850 mb and 900 mb wind speeds off the North-Central Oregon coast 15Z
today. Wind speeds diminish from north to south later this morning as
the front sags southeast. Again, the main forecast challenge will be
the actual frontal location by early afternoon. There is also a high
wind watch valid late this afternoon through this evening. Overall
confidence in this event is less than optimum. 06Z NAM and GFS have
come more into line showing a secondary low pressure area developing
out near 140W early this morning and then continuing to deepen today
as it heads toward the Washington coast. The ECMWF does not have near
the surface reflection as the NAM or GFS. The NAM indicates 65-75 kt
850 mb and 900 mb wind speeds along the Central Oregon coast early
this evening. With the current warning in place, will punt to the day
shift on the high wind watch.
Snow levels continue to hover around 3500-4000 feet in the Cascades
per surface observations. It should be noted that temperatures have
fallen across the upper Hood River valley and we could see
precipitation begin to mix with snow above 2000-2500 feet this
morning. The NAM & WRF-ARW wet bulb zero heights support this idea as
cold air banks up against the Cascades. Do not foresee major
accumulations at these elevations, but still something worth
monitoring.
Models continue to vary considerably on what becomes of the
aforementioned baroclinic boundary, which leads to difficult QPF
forecast challenges. The GEM, EC & WRF-ARW models hold the heaviest
QPF over the Nehalem, Wilson, Nestucca and Siletz River Basins today
while the latest GFS & HRRR runs suggest the front will likely drop
southward this morning and end up over the Alsea and Siuslaw River
drainages by midday. The GFS & HRRR runs would be less likely to
produce river flooding as the heaviest rainfall would likely not sit
over any given drainage too long. The 06Z GFS has the heaviest rain
this afternoon over the North Oregon coast basins, then slowly shifts
the focus south late this afternoon and tonight. By Friday morning
the front has weakened with the primary dynamics over far SW Oregon
and NW California. But, the front never goes completely away. The
GFS, and to a certain extent the ECMWF, lift the frontal remains
north Fri evening and Fri night as a colder upper level trough pushes
toward the coast.
Snow levels will vary quite a bit across the Cascades today and
tonight. Cold air will likely be stubborn to scour out across the
south Washington Cascades especially near Mt Adams where 10-20 inches
of snow appear likely above 3500' and somewhere between 15-30 inches
above 4500'. Warm air streaming northeastward ahead of the front
should result in snow levels rising to around 4500 feet this
afternoon across the Oregon Cascades. This process will be slowest to
occur near Mt Hood so the current Winter Wx Advisory looks on track.
The good news is that this should bring a period of improved travel
conditions for those traveling across the Cascade passes today.
The cold upper trough Saturday will keep snow levels below the
passes. QPF will not be all that impressive, but snow will continue
to accumulate above the passes. Weishaar
.LONG TERM...(Saturday night through Wednesday)...No Changes...
Previous Discussion from Wednesday afternoon follows...The active
weather pattern looks to continue through much of the long term
forecast as a series of storm systems move across the Pac NW. Models
continue to show an upper level trough moving across the forecast
area Saturday night and Sunday which will maintain showers over the
region. Snow levels look to lower to around 2500 ft on Sunday, with
an additional 3 to 6 inches possible at the Cascade passes. If you
are planning on traveling over the Cascades, prepare for hazardous
road conditions.
Models then show a weak upper level shortwave dropping southeastward
Sunday night and Monday. This system looks to bring another round of
rain to the area late Sunday/early Monday, with cool northwesterly
flow keeping showers going on Monday. High pressure looks to build
across the area Monday night and Tuesday bring with it a period of
quieter weather and raising snow levels to around 4500 ft. However,
this bring will be short as models show another upper level trough
dropping south out of the Gulf of Alaska Tuesday night and Wednesday
which could bring another round of heavy rain and Cascade snow, with
locally windy conditions. /64
&&
.AVIATION...Primarily VFR early this morning with occasional MVFR
CIGS and VIS at the coast. This should trend toward more MVFR
conditions this morning at the coast. A band of thunderstorms
stretching from near KAST southwest over the coastal waters. If
current trends continue most of the coastal areas will see some
thunderstorms through about 15Z as the band shifts east. Southerly
wind gusting 30 to 40 kt right along the coast will ease later
this morning as a cold front moves ashore. South winds appear to
increase again with gusts 30 to 40 knots Thursday evening but
there is significant model uncertainty regarding the track of a
potential surface low and even it's possible existence versus on
open surface trough. 06Z model runs are in better agreement but
still have significant differences in the details.
Inland areas remain generally VFR into this evening, but areas
from KSLE northward have better chances for MVFR CIGS and VIS
after 21Z Thu as heavier precipitation leans further inland.
KPDX AND APPROACHES...VFR prevailing through about 21Z Thu
then a good chance for MVFR CIGS in the 2000 to 3000 ft range to
occasionally affect the TAF sites. MVFR conditions may continue
through tonight into early Fri.
&&
.MARINE...A band of thunderstorms extending southwest from near
Astoria will continue to slide east as a cold front pushes toward
the coast. The cold front may be further back from the convection
but valuable information from buoy 46029 shows pressure rises and
a slight windshift and decrease in wind. Hires wind models are
fairly close to the observation and this will push the front
through Astoria around 4 am, then slide down the coast to Florence
by 10 am if not a couple of hours earlier. Seas appear to have hit
its peak around 20 ft around 1 am for the northern waters, but the
central Oregon coastal waters may still a bump to 22 ft early this
morning. Seas will gradually subside this morning but remain above
15 feet through Friday with a bump back up to near 20 ft this
evening with the next system.
Models have not done well with this system for Thu evening. The
track and strength of this second system keeps changing in small
but impactful ways, leading to more uncertainty. The 06Z models
are in slightly better agreement but confidence in the forecast is
still not very high. But a decision has to be made so will
convert the Storm Watch to a Gale Warning starting late this
afternoon through late evening. Feel fairly confident that the
waters south of Cascade Head will see gales, and possibly a short
period of near storm force gusts early this evening. North of
Cascade Head confidence is lower as model solutions vary from
Small Craft Advisory to Gale force winds.
Friday things start to calm down, with winds and seas coming back
down. Still think we will see small craft advisory winds through
most of the day on Friday, though winds should drop below 20 kt
by Friday evening. Seas should drop back down into the mid-teens
by Friday evening as well. Weaker fronts move across the waters
over the weekend, but generally seas expected to drop to around 9 ft
by Saturday night or Sunday, and winds stay fairly benign for this
time of year. /mh
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...Winter Weather Advisory until 4 AM PST Friday for Northern
Oregon Cascades.
High Wind Warning until 10 AM PST this morning for Central
Oregon Coast-North Oregon Coast.
Flood Watch from 10 AM PST this morning through Friday evening
for Central Coast Range of Western Oregon-Central Oregon
Coast-Central Willamette Valley-Coast Range of Northwest
Oregon-Greater Portland Metro Area-North Oregon Coast-
South Willamette Valley.
High Wind Watch from this afternoon through this evening for
Central Oregon Coast-North Oregon Coast.
WA...Winter Storm Warning until 4 AM PST Friday for South Washington
Cascades.
Flood Watch from 10 AM PST this morning through Friday evening
for South Washington Coast.
High Wind Watch from this afternoon through this evening for
South Washington Coast.
PZ...Gale Warning until 10 AM PST this morning for Coastal Waters
from Cape Shoalwater WA to Florence OR out 60 nm.
Gale Warning from 1 PM this afternoon to midnight PST tonight
for Coastal Waters from Cape Shoalwater WA to Florence OR
out 60 nm.
Small Craft Advisory for Rough Columbia River Bar until 4 PM
PST this afternoon.
&&
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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.1 heavy snow. Local standard time, as filed.
Multiple locations around 4000' and above recorded 12-20 of snow. Highest amounts observed were recorded at Pinto Rock SNOTEL at 4440' elevation and Lone Pine SNOTEL at 3930' elevation, which both recorded 20 inches of snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2016Every state in 2016This day in weather historyWarnings in Washington, November 2016
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: 667826.