A strong upper-level trough brought about SW winds aloft and thus a strong downsloping wind event across the foothills of the Blue Mountains the night of March 8 and through the overnight hours into March 9.
Every event with a place to put it; 1 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 strong upper-level trough brought about SW winds aloft and thus a strong downsloping wind event across the foothills of the Blue Mountains the night of March 8 and through the overnight hours into March 9.
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 8, 2:09 PM PST, 4 hours 51 minutes earlier.
Area Forecast Discussion
National Weather Service Pendleton OR
209 PM PST Fri Mar 8 2024
.SHORT TERM...Tonight through Sunday night...An elongated upper
level ridge with a slight positive tilt extends from Alberta down
to the CA coast. The axis of the ridge is over the CWA, resulting
in a seasonably warm and dry day. Meanwhile, an elongated upper
level trough is between 130-140W and is forcing the ridge to the
east. This trough will quickly travel across WA/OR tonight and
Saturday. The biggest impact for our area will be the very windy
conditions that will set up along the Blue Mountain foothills
east-southeast of Pendleton and Milton-Freewater as well as the
Grande Ronde Valley. 850mb winds from the SSE will increase to
around 40-45kts tonight, and a lee side low will set up west of
the northern Blue Mtns. Surface gradients from BKE-MEH will be as
strong as 8mb early Saturday morning from the deterministic
models, and almost half of the HREF members show wind gusts at
55-63 mph near the Cabbage Hill area while the other half show
gusts 45-55 mph. Since I-84 near Cabbage Hill is a highly traveled
and wind proned area, a High Wind Warning was issued for the base
of the northern Blue Mountains from 7 PM tonight through 10 AM
Saturday. I kept the wind advisory for the Grande Ronde Valley,
but I can't rule out that the base of Ladd Canyon will observe
gusts as high as 55-60 mph. After 10 AM Saturday, wind directions
will shift to a more SW direction which often leads to a sharp
decrease in the winds near Cabbage Hill and Mission. However, the
Grande Ronde Valley will continue to observe 45-50 mph gusts and
most of the lower elevations will observe 35-45 mph gusts
(confidence 70%).
The fast moving system will do little in terms of precipitation
and snowfall amounts through Sunday morning. Only the highest
peaks of the Cascades will receive anything more than 3 inches.
Santiam Pass is forecast to receive 1-3 inches while the other
mountain passes will observe one inch or less.
The forecast area will be between systems Saturday evening for a
break in precipitation before the next trough arrives on Sunday.
There will be another round of snow for the Cascades with better
potential for moderate snow, mainly near the crest. Forecast will
show 2-5 inches below 4000 feet and 5-10 inches above 4000 feet.
Confidence wasn't quite high enough for a Winter Weather Advisory
but one may be needed if accumulations are more than currently
forecast. Snow amounts will be less than 3 inches for most of the
eastern mountains (significantly higher for the Eagle Cap
Wilderness). It will be a breezy spring day as well with SSW winds
10-20G30 mph for many areas. Wister/85
.LONG TERM...Monday through Friday...Sensible weather concerns
through the extended forecast will revolve around a period of
active weather early in the work week as a series of troughs
continue to move through the area. Light to moderate snow in the
mountains with light rain in the lower elevations will be possible
through early Wednesday. Wednesday afternoon through Friday will
be mainly dry with little in the way of weather concerns.
Monday, ensemble guidance is in good agreement in a shortwave
departing the region to the east and a difluent westerly flow
setting up over the PacNW. This will mostly result in light snow
showers across the mountain zones, while rainshadowing east of the
Cascades keeps the lower elevations relatively dry. By late Monday
afternoon, ensemble guidance advertises the arrival of a cold
front to the PacNW with an upper trough beginning to dive down
from the Gulf of Alaska. The cold front is expected to move across
the PacNW overnight Monday, while being followed up by the trough
moving across the region through much of Tuesday. The combination
of the two synoptic features is expected to bring moderate to
locally heavy snow accumulations along the Cascade crest above
4,500 feet, while snow accumulations across the rest of the
mountain areas will remain light. Along the crest of the Cascades
above 4,500 feet, current NBM and ensemble cluster guidance show
45-60% probabilities of exceeding 6 inches of snow accumulations
by Tuesday morning, while by Wednesday morning the OR Cascades
will see a 70-85% chance and the WA Cascades 50-65% chance. Across
the rest of the mountain areas, there is moderate (55-65%)
confidence in snow accumulations between 2-5 inches through the
Monday-Tuesday time period.
Wednesday, ensemble guidance continues to be in great agreement
that the upper trough will exit to the southeast of the PacNW
during the first half of the day, with a brief period of Northwest
flow aloft developing over the region. This will result in only
light snow showers continuing across the mountains through
Wednesday evening, with only a 40-60% chance along the Cascades
and 20-30% chance along the northern Blues of an additional 2
inches of snowfall. As for the other mountain areas, additional
accumulations Wednesday will be under an inch (confidence 60%).
Late Wednesday into Friday, ensemble guidance shows very little
disagreement in an upper level ridge gradually building over
western CONUS. This will result in dry conditions developing in
the latter half of the week with warming temperatures area-wide.
Lawhorn/82
&&
.AVIATION...00Z TAFs...VFR conditions to prevail through the
period. CIGs are expected to remain above 12kft AGL through this
evening, with increasing cloud cover between 5kft to 10kft AGL
expected at all sites tomorrow. A weather system approaching the
region will result in increasing precipitation chances across the
mountains, but only around 30% chances of precipitation at sites
DLS/PDT/ALW. Winds will generally remain less than 12kts through
tonight, but southerly winds will increase to 12-17kts with gusts
up to 25kts at most sites tomorrow except site PSC where winds
will be less than 12kts. Lawhorn/82
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 33 52 36 55 / 0 30 20 50
ALW 36 53 37 55 / 0 40 40 70
PSC 33 54 37 59 / 0 20 10 40
YKM 30 53 32 53 / 0 10 10 40
HRI 31 53 37 58 / 0 30 10 40
ELN 31 49 31 49 / 0 10 10 50
RDM 31 48 32 49 / 0 20 0 40
LGD 31 45 32 46 / 0 20 30 60
GCD 26 47 31 48 / 0 40 10 60
DLS 35 54 37 52 / 0 30 30 70
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory from 7 PM this evening to 3 PM PST Saturday for
ORZ049.
High Wind Warning from 7 PM this evening to 10 AM PST Saturday
for ORZ507.
WA...None.
&&
SHORT TERM...85
LONG TERM....82
AVIATION...82The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Cabbage Hill ODOT sensor reported a wind gust of 70 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2024Every state in 2024This day in weather historyWarnings in Oregon, March 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: 1165724.