Snow fall was heavy above 4500 feet in the Northern Blue Mountains of Northeast Oregon 17th of March 2018. This snowfall was due to moisture wrapping around from the east on the north side of an upper low.
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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.
Snow fall was heavy above 4500 feet in the Northern Blue Mountains of Northeast Oregon 17th of March 2018. This snowfall was due to moisture wrapping around from the east on the north side of an upper low.
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 Mar 17, 3:15 AM PST, 2 hours 15 minutes earlier.
Area Forecast Discussion...Updated
National Weather Service Pendleton OR
415 AM PDT Sat Mar 17 2018
Updated Aviation Discussion
.SHORT TERM...Today through Monday...A large upper low pressure
system continues to spin over southwest Oregon this morning. Wrap
around moisture from this low is pushing rain and mountain snow
showers over mainly Oregon, but there are some showers too in
Washington. The greatest chance of accumulating snow is over the
south central and the northeast portion of the forecast area, i.e.
the John Day Highlands, the John Day Basin and also Wallowa County
where there are currently Winter Weather Advisories in effect today
through noon for the John Day Basin and through 4 PM (23Z) over the
John Day Highlands and Wallowa County. Snow amounts will just be
enough to warrant these advisories. Elsewhere there will be rain and
mountain snow showers. The upper low will weaken as it tracks to the
east across southern Oregon today. Precipitation will gradually
taper off tonight through Sunday night with areal coverage of
showers will be decreasing. By Monday morning most areas will be dry
except the areas along the Idaho border, and the portion of the CWA
that borders MFR's area of responsibility (south central Oregon).
There may also be some lingering showers over the northern Blue
Mountains as well as the Cascade east slopes. Then another upper low
will track southward along the Oregon/Washington coast by late
Monday, which will bring another chance of rain and mountain snow
showers to southern portions of the CWA as well as the Cascade east
slopes and the Blue Mountains by Monday evening. There will be a
slow warming trend through the short term, however by only a couple
degrees each day. However, it will remain cooler than normal for mid
March with temperatures in the 50s in the lower elevations and 30s
to 40s over the mountains. Winds will be light throughout the short
term forecast period. 88
.LONG TERM...Monday Night Through Friday...A series of upper level
troughs will move through WA and OR during the extended time period.
An upper level low and associated trough will move across OR with a
few showers Monday night and Tuesday. Another trough will move
toward the coast Tuesday night with rain and high elevation snow
moving into eastern WA and OR. Snow levels Tuesday night and
Wednesday will be 4000-5000 feet. This system will bring increasing
PoPs Wednesday with rain and snow. Snow levels rise to 6000 feet
Wednesday night due to broad southerly flow ahead of another trough
approaching the coast. This trough will move slowly across WA and OR
Thursday and Friday with rain and snow likely. Snow levels will
start mainly above 5000 feet Thursday then decrease to 1000-1500
feet Friday. Coonfield
&&
.AVIATION...12Z TAFs...A broad upper level low will keep conditions
moist and unstable through 03-06Z. Areas of rain and/or snow showers
move either near or over most TAF sites at some point today. Best
chances of showers will occur during the morning and early afternoon
hours at KRDM, KBDN, KALW and KPDT. Shower chances will be more
limited at KDLS KPSC and KYKM. Cigs/vis will mainly be VFR. MVFR
conditions will be possible at KALW KPDT KRDM and KBDN due to
upslope flow and the shower activity. Winds will generally be 5 to
15 kts through the period, though KDLS may have winds of 15 to 20
kts Saturday afternoon. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 50 32 50 33 / 40 30 10 10
ALW 52 35 51 33 / 50 40 10 10
PSC 56 34 56 32 / 20 10 10 0
YKM 59 32 55 31 / 10 0 10 10
HRI 55 34 54 33 / 30 20 10 0
ELN 55 31 51 30 / 10 10 10 10
RDM 47 24 46 24 / 60 20 10 10
LGD 42 31 43 28 / 70 70 20 10
GCD 41 28 42 29 / 80 50 10 10
DLS 57 34 54 34 / 20 10 10 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Winter Weather Advisory until 4 PM PDT this afternoon for
ORZ050- 506.
Winter Weather Advisory until noon PDT today for ORZ505.
WA...None.
&&
88/76/76The national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
Snow accumulation of 11 inches at Milk Shakes SNOTEL in Wallowa county by 400 LST on the 18th. Also had 11 inches reported at Tollgate by noon on the 17th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2018Every state in 2018This day in weather historyWarnings in Oregon, March 2018
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: 745130.