Locally high wind gusts occurred near the south end of the Wallowa valley in Wallowa county due to a low pressure system moving through southeast Washington state.
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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.
Locally high wind gusts occurred near the south end of the Wallowa valley in Wallowa county due to a low pressure system moving through southeast Washington state.
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 Nov 26, 9:25 AM PST, 1 hour 30 minutes earlier.
Area Forecast Discussion...Updated
National Weather Service Pendleton OR
925 AM PST Sun Nov 26 2017
Updated Aviation Discussion
.UPDATE...Significant updates were performed on temperatures
already as they have soared to nearly 60 degrees in central oregon
these last couple of hours and the winds increased. Temps across
a number of other locations have been increased such as the john
day area...the foothills of the blue mountains and over wallowa
county where they have climbed into the 60s already. In addition
the forecast winds have been increased across a number of
locations this morning and during the aftn along with forecast
high temps. The challenge will continue to be with winds that are
able to mix out the stable area near the surface to create a
downslope warming effect that will increase temps. A low pressure
system off the pacnw was responsible for the regions complex
weather today and this will approach the two state area and bring
showers to the area. As the system races across the region today
pressure gradients will continue to tighten creating breezy to
windy conditions and wind advisories have been hoisted across some
locations today.
&&
.AVIATION...18Z TAFs...Several aviation concerns are anticipated
with the frontal passage today. CIGS will lower and showers will
begin at KYKM and KDLS around 20Z then the remainder of the TAF
sites between 20Z-00Z. The areas likely to receive MVFR or less in
moderate rain will be KPDT and KALW. If the surface inversion breaks
ahead of the front at KPDT strong southerly winds will mix to the
surface. The inversion may break at KALW as well. Winds have already
increased at KRDM and KBDN. Winds will shift directions after the
FROPA at all stations and increase speeds at KPSC and KYKM. LLWS may
also be experienced today, especially at KPSC KRDM and KBDN. 76
&&
.PREV DISCUSSION... /issued 335 AM PST Sun Nov 26 2017/
SHORT TERM...Today through Tuesday...An upper ridge will persist
over the inland west with a moist southwest flow on the back side of
the ridge over the CWA today. Main forecast concern for this package
will be increasing southerly winds over the eastern mountains and
passes as well as the base of the Blue Mountains (the Foothills).
Also included is the southern Grande Ronde Valley and the Wallowa
Valley. These areas will have the strongest winds this morning ahead
of an approaching cold front. Winds in these areas will likely be
strong enough for a wind advisory and will keep the current advisory
in effect for this morning...and into the afternoon. There will be a
period of rain as the cold front moves through the CWA and then
showers behind it...especially in the eastern and northeast
mountains where the winds will become upslope. This will be about
the time that the wind advisory for strong southerly winds will end
due to a shift in the pressure gradients as the cold front passes.
There will be a break in the weather for Monday before the next
weather system moves into the region on Tuesday. This next system
will likely bring more precipitation to the area with another
Pacific cold front. This time pressure gradients will be mostly
westerly and the strongest winds will likely be over the Cascades
and along the east slopes. Snow levels will be high today between
8000-9000 feet MSL this morning...and then they will gradually lower
each day...to 3500-4500 feet MSL by Tuesday morning. These will be
low enough such that there may some light snow accumulations in the
mountains. At this time it is hard to say how much snow...but will
need to keep a close watch in case an advisory is needed. 88
LONG TERM...Tuesday Night through Saturday. Models in general
agreement with the synoptic pattern but appear to be stronger and
wetter with a cold front Friday night and Saturday compared to
previous runs. A shortwave trough and surface cold front will sweep
east of the Cascades Tuesday night, exiting the region after
midnight Wednesday. Snow levels will lower to around 2500-3000 feet,
but the fast moving cold front will only bring light accumulations
of snow. Breezy winds will accompany the front. Although Wednesday
will primarily be a dry day due to a weak transitory ridge, a
northwest flow aloft Wednesday morning may bring orographic light
snow showers over the Blues and Wallowas. Dry with patchy fog or
freezing fog is expected Wednesday night and Thursday. The next
cold front is progged to approach the WA coast Thursday afternoon
then along the WA Cascades Thursday night. 00Z models are trending
a little faster and spread precipitation as far east as the Tri-
Cities down toward Boardman by early Friday morning. Will hold off
on the faster timing but will increase PoPs Friday. According to
the 00Z GFS and ECMWF, the front will become stationary in a line
from Wallowa County across the Oregon Blue Mountains then southwest
toward Sisters for most of Friday, Friday night and into Saturday
morning. If the models continue to advertise the low snow levels
(3500-4500 feet Friday lowering to around 3000 feet Saturday) and
the stationary front, there could be at least a 24-hour period of
steady snow over the mountains of central and northeast Oregon. A
shortwave trough on Saturday will bring a chance of rain and snow
showers to all zones. Wister
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 59 35 52 36 / 70 50 10 10
ALW 63 38 54 38 / 60 70 10 10
PSC 51 38 54 37 / 60 30 0 10
YKM 44 34 49 35 / 40 20 10 30
HRI 51 33 52 36 / 60 30 0 10
ELN 43 32 44 33 / 50 20 10 30
RDM 62 29 47 29 / 50 30 10 10
LGD 58 32 46 34 / 50 80 10 20
GCD 63 35 45 33 / 50 80 10 10
DLS 48 38 51 39 / 50 30 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory until 3 PM PST this afternoon for ORZ049-050-507-
508.
WA...None.
&&
97/The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Peak gust of 66 mph at 420 PM PST, 2 miles north of Joseph in Wallowa county. There were seven other sporadic gusts between 58 and 64 mph at this locations during the period. Sustained winds at time of peak gust were 26 mph.
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, November 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: 725098.