A major Pacific storm brought snow to most of the forecast area. Heaviest snows occurred from south-central Washington south to central Oregon.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 PDT wrote it up.
A major Pacific storm brought snow to most of the forecast area. Heaviest snows occurred from south-central Washington south to central 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 Pendleton, OR wrote its last area forecast discussion before the first event at Dec 7, 9:16 PM PST, 3 hours 44 minutes earlier.
Area Forecast Discussion
National Weather Service Pendleton OR
916 PM PST Wed Dec 7 2016
.UPDATE...Forecast was updated with the latest model guidance as our
next winter storm approaches the area. The main updates were to
tweak PoPs, QPF, snow amounts and temperatures for tonight through
Friday. Overall QPF and snow amounts were adjusted up slightly in
most areas based on the latest data. Temperatures were significantly
lowered tomorrow with most areas staying in the 20s through the day.
Only a few spots in far southern Deschutes County may reach the
freezing mark on Thursday...this means frozen or freezing precip for
much of the CWA through Friday AM. Current thinking is that precip
will start off as all snow over Central Oregon prior to 10 AM
Thursday, then spread north and east through the afternoon hours.
Snow will reach the 395 corridor during the early afternoon hours.
Snow could begin to mix with sleet, and eventually freezing rain
during the late afternoon and evening hours across Central Oregon,
mainly south of hwy 26. Periods of snow will continue across all of
northern Oregon and Southern Washington into Thursday evening.
Blowing and drifting snow will be a concern in the Grande Ronde
Valley with south winds 20-35 MPH Thursday evening. Snow and mixed
precip will taper off and nearly end late Thursday night and Friday
morning for all lower elevations...except perhaps the Columbia
Gorge. This will mean just flurries or some freezing drizzle after
midnight and into Friday morning for the Lower Columbia Basin,
Foothills, surrounding valleys and Central Oregon. The next round of
precip moves in Friday afternoon, night and into Saturday for more
mixed precip in the lower elevations and snow in the mountains.
Temperatures will warm well above freezing Friday afternoon across
Central Oregon and the John Day basin...so expect just rain showers
here.
The previous winter storm watches will be upgraded to advisories and
also warnings for the Simcoe Highlands and the Southern Blue
Mountain Foothills. Advisories will also be added for the Grande
Ronde Valley, Wallowa County and the Southern Blue Mountains. 77
.AVIATION...06z tafs. Increasing mid and high level clouds tonight
with ceilings bkn 100-200. Winds 5-10kt. Warm front moving across
the area Thu with snow at all taf sites. Ceilings lowering to bkn-
ovc 020-040 with visibility 2-5sm in snow. Winds 5-15kt. Expecting
snow accumulations at all taf sites. 94
&&
.PREV DISCUSSION... /issued 323 PM PST Wed Dec 7 2016/
SHORT TERM...Tonight through Friday. A complex pattern will set up
over the Pacific NW through the short term period...and many
forecast challenges were encountered. Multiple Winter Storm
Watches, Warnings and Advisories will be issued for the afternoon
package. The Winter Storm Watches for the East Slopes of the WA
Cascades...the Eastern Columbia River Gorge and North Central Oregon
will be upgraded to Winter Storm Warnings for heavy snow and the
potential for freezing precipitation. Snow will begin to develop
along the East Slopes of the Oregon Cascades in Deschutes County and
the Bend/Redmond areas around 5 AM Thursday. The snow will then
spread over the remainder of eastern Oregon and eastern Washington
during the day. The warm front bringing the precipitation is
arriving slower than previously anticipated...and most of our
eastern Washington zones will not see snow develop until after 12 PM
Thursday. Models have also backed off on the QPF for the area due
to a more stretched out warm front and a surface low farther west
than previous runs were advertising. Therefore...snow amounts in
the Kittitas/Yakima Valleys...the Simcoe Highlands...the Lower
Columbia Basin and Blue Mtn Foothills will be less than the previous
forecast indicated and should only meet advisory criteria. Rather
than making a decision to downgrade the watch to an advisory...will
let the next shift analyze the system and decide the best highlights
(if any) for these areas. Forecasters will also need to consider
where freezing rain or sleet may occur due to the weak warm air
advection expected. The timing of the Winter Storm Watch will be
changed to reflect the slower moving front.
Winter Weather Advisories will be issued for the Blue Mtns...the
John Day Basin...and the Ochoco Mountains. Snow amounts of 2-4
inches are forecast for the John Day Basin and 3-5 inches in the
Ochoco Mountains on Thursday before warm air spreads and increases
snow levels to around 3500-4000 feet. In the Blue Mtns...light snow
will be continue from Thursday afternoon through Friday night...and
this will be a prolonged light to moderate snow event. Snow amounts
in the Grande Ronde Valley and Wallowa County are not expected to
become significant...but windy conditions in the Grande Ronde Valley
late Thursday will cause blowing and drifting of snow. Wister
LONG TERM...Friday night through Wednesday...Extended models have
come into better agreement through the extended period so confidence
is better than yesterdays low confidence but still need some
consistency over the coming model runs.
A cold front will be passing over the region Friday night and snow
levels will vary due to the cold pool trapped in the Columbia Basin.
Most precipitation type will be snow but could see some wintery mix
over portions of the Basin. This will leave us in a west to
northwest flow over the weekend with small shortwaves passing over
the region. Precipitation will taper off Saturday to showers before
another system increases precipitation late Sunday and Sunday night.
A small upper level ridge will begin to build first of next week
which will begin to turn the flow more southwesterly. The new trend
in the models is to bring some warm fronts into the region tuesday
and Wednesday associated with this building ridge pattern. However,c
confidence in this solution is low at this time as models have had
issues agreeing over the past couple of days. Overall the weather
pattern looks to remain active with wintery weather impacting the
forecast area through the long term forecast period.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 7 22 20 31 / 0 90 80 60
ALW 11 26 25 33 / 0 80 90 50
PSC 13 25 23 30 / 0 80 80 50
YKM 15 25 19 26 / 0 80 90 50
HRI 11 25 22 29 / 0 90 80 60
ELN 11 24 20 26 / 0 50 90 60
RDM 8 23 23 42 / 20 80 50 50
LGD 5 21 23 38 / 0 80 80 70
GCD 10 24 33 41 / 0 90 70 60
DLS 21 26 23 28 / 0 100 90 70
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Winter Weather Advisory from 4 AM to 10 PM PST Thursday for
ORZ509-511.
Winter Storm Warning from 7 AM to 10 PM PST Thursday for ORZ510.
Winter Weather Advisory from 11 AM Thursday to 4 AM PST Saturday
for ORZ503.
Winter Weather Advisory from 1 PM Thursday to 4 AM PST Friday
for ORZ050.
Winter Weather Advisory from noon Thursday to 4 AM PST Saturday
for ORZ502.
Winter Weather Advisory from 11 AM Thursday to 1 AM PST Friday
for ORZ044-507.
Winter Storm Warning from 10 AM to 7 PM PST Thursday for ORZ041.
Winter Weather Advisory from 11 AM Thursday to 4 AM PST Friday
for ORZ049.
Winter Weather Advisory from 7 AM to 10 PM PST Thursday for
ORZ505-506.
Winter Storm Warning from 10 AM Thursday to 1 AM PST Friday for
ORZ508.
WA...Winter Weather Advisory from noon Thursday to 4 AM PST Saturday
for WAZ030.
Winter Weather Advisory from 11 AM Thursday to 1 AM PST Friday
for WAZ026>029.
Winter Storm Warning from 11 AM Thursday to 3 PM PST Saturday
for WAZ521.
Winter Storm Warning from 10 AM to 7 PM PST Thursday for WAZ024.
Winter Storm Warning from noon Thursday to 3 PM PST Saturday for
WAZ520.
&&
77/91/94The national radar mosaic for the moment the first event began.
5 heavy snow. Local standard time, as filed.
Measured heavy snow of 8 inches 9 miles west of La Pine. Also 8 inches of snow 9 miles east-southeast of Bend.
Measured heavy snow of 7 inches fell at the Prineville airport by early afternoon of the 8th. Also a retired NWS employee measured 7 inches of snow in Bend.
Measured heavy snow of 5 inches 9 miles west-southwest of Dufur in Wasco county. Also 4 inches of snow in southern Wasco county, 8 miles northeast of Warm Springs.
Measured heavy snow of 7 inches 1 mile west of the City of The Dalles during this period. Also 6 inches of snow accumulated 4 miles east of Mosier.
Measured heavy snow of 5.3 inches in west Condon, Gilliam county. Also 4 inches of snow accumulated near Mayville, 10 miles south of Condon.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2016Every state in 2016This day in weather historyWarnings in Oregon, December 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: 664801, 662584, 664802, 664804, 664803.