A cold front passage during the morning produced strong winds across some exposed ridges along Washington Cascade east slopes and through portions of the Washington Columbia Basin.
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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.
A cold front passage during the morning produced strong winds across some exposed ridges along Washington Cascade east slopes and through portions of the Washington Columbia Basin.
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 18, 3:25 AM PST, 35 minutes earlier.
Area Forecast Discussion
National Weather Service Pendleton OR
325 AM PST Wed Dec 18 2024
.SHORT TERM...Today through Thursday...A cold front is passing over
the Cascades at this time and will sweep across the forecast area
this morning before exiting to the east in the afternoon. This will
push a band of of fast moving precipitation across the forecast area
then turn to some lingering showers over the mountains in the
afternoon before ending. Snow levels will lower allowing for some
minimal snow accumulations in the mountains before precipitation
ends.
Southerly winds ahead of the front will turn westerly behind the
frontal passage. Could see some wind gusts around 45 mph during and
after the frontal passage. Some wind advisories are in effect along
the Foothills of the Blue Mountains and southern Grande Ronde Valley
through this morning. Winds will begin to decrease in the afternoon.
A ridge of high pressure will move over the region Wednesday night
through Thursday. This will lead to some shallow inversions
Wednesday night and some patchy fog development around the Lower
Columbia Basin. A southwest flow will begin to bring some moisture
into western Washington Thursday clipping the Cascades with some low
chance POPs and light precipitation. JS/OVERANDOUT!
.LONG TERM...Friday through Wednesday...Dry conditions continue
Friday through Saturday morning as the upper ridge moves across the
PacNW. However, the arrival of these progressive systems will return
with rain and mountain snow from Saturday night onwards. About 1" of
QPF amounts may develop for the WA/OR Cascades with 0.50" or below
for the Blues and lowlands (30-70% chance). QPF amounts could
increase to 2" of rain Tuesday over the crest of the Cascades but
confidence remains low (15-30%). Breezy winds (up to 25 mph) develop
Saturday at the Grande Ronde Valley and the Wallowas. Due to tighten
surface gradients, these winds may extend across the rest of the
forecast area Sunday night onwards. Snow levels remain between 4.5-
6.5kft through Tuesday night before decreasing to 3.5-4.5 kft
Wednesday. There is a 30-50% chance for 2" of mountain snow or less
accumulating at the crest of the Cascades Monday into Tuesday. With
the next system arriving, snow may increase to 4" or higher
Wednesday, though confidence is low (<30%). Feaster/97
&&
.AVIATION...12Z TAFs...Mixture of flight categories will persist
this morning for KDLS and KYKM with KPSC currently in MVFR. The
remaining sites will be in VFR. Based on current radar imagery, the
system begins moving across the forecast area with oncoming showers
at the WA/OR Cascades (KDLS/KYKM) and Lower Columbia Basin (KPSC).
This will bring rain, mist and some fog for mainly KDLS and KYKM,
lowering their CIGs and VSBYs. Gusts will develop for most sites at
around 25-35 kts this morning into afternoon with sustained winds at
11-23 kts. KDLS will have winds less than 10 kts. Feaster/97
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 54 33 45 35 / 50 0 0 0
ALW 53 36 46 38 / 80 0 0 0
PSC 55 36 40 37 / 30 0 0 0
YKM 47 29 38 33 / 50 0 0 0
HRI 55 36 41 37 / 30 0 0 0
ELN 44 28 38 32 / 60 0 0 10
RDM 49 29 47 36 / 40 0 0 0
LGD 48 30 45 33 / 70 0 0 0
GCD 48 28 46 33 / 40 0 0 0
DLS 53 37 44 39 / 80 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory until 10 AM PST this morning for ORZ049-507-508.
WA...Winter Weather Advisory until 4 AM PST early this morning for
WAZ026-522-523.
Wind Advisory until 1 PM PST this afternoon for WAZ029.
&&
SHORT TERM...91
LONG TERM....97
AVIATION...97The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
The mesonet station HARMY 14 miles north northwest of West Richland recorded a 67mph gust at 0715 PST on December 18th. The mesonet station PC048 Nine Mile Hill 14 miles southeast of Burbank measured a wind gust of 58mph at 1020 PST December 18th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2024Every state in 2024This day in weather historyWarnings in Washington, December 2024
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: 1228187.