A series of winter systems moved through the region starting Thursday Jan. 11th through Saturday Jan.
Every event with a place to put it; 2 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 series of winter systems moved through the region starting Thursday Jan. 11th through Saturday Jan. 13th, and produced moderate to heavy snow across much of the forecast area. Persistent northwest flow aloft also sustained snow showers across the mountains between the systems. The second system was far more productive, with many lower elevation areas seeing 4-7 inches and locally higher of additional accumulating snow during this period of time.
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 Feb 12, 8:47 AM PST, 13 minutes earlier.
Area Forecast Discussion
National Weather Service Pendleton OR
847 AM PST Fri Feb 12 2021
.MORNING UPDATE...Snow currently falling across the northern half
of the forecast area will continue today while southern portions
will see periodic bands of snow. Snow intensity through this
afternoon will be quite light, with bands of moderate snow
possible in the mountains, but will pick up once again tonight as
the next weather system approaches the forecast area. Shortwave
trough will approach the region from the northwest tonight, with a
leading westerly to southwesterly flow aloft that will push some
moisture east of the Cascades. With a slight increase in moisture,
this system is looking to be more potent than the system yesterday
with snow accumulations through Saturday afternoon of 2-4 inches
in lower elevations of southern WA and central OR, 3-6 inches
across the Blue Mountain foothills in WA/OR and Lower Columbia
Basin/Gorge in OR, and 6-10 inches possible across the mountains
with locally higher amounts near the Cascade crests. Snow will
briefly diminish across the forecast Saturday and early Sunday
before another system arrives. Afternoon highs today will be in
the teens and 20s mountains while overnight lows tonight will be
in the single digits to teens. Lawhorn/82
&&
.PREV DISCUSSION... /issued 403 AM PST Fri Feb 12 2021/
SHORT TERM...
Today through Sunday night...
Two systems will be affecting the region during the short term
period.
The first system is currently upon us, and will be winding down
through the morning hours everywhere except for the Cascades.
Overall this system has likely underperformed in most locations.
The second system will move in right behind it later today into
and ramp up tonight before winding down Saturday evening. Guidance
continues to suggest that this is a stronger, wetter system.
However, I can't help but wonder based on recent model
performance iff this one will underperform as well. While there is
some decent omega toward Saturday morning, all of the better
dynamics are over the Cascades and on the west side.
Nevertheless, temperatures will be quite cold...only in the teens
and 20s and snow ratios will be high, so whatever moisture there
is will lead to a fluffy snow and it won't take much moisture to
lead to decent accumulations.
Based on all of this, will not be making any changes to the
current headlines. Will wait to see if any changes are needed
(snow amounts need to be increased or decreased etc) as the next
system moves in.
The second system will end Saturday night and Sunday looks dry
over most of the area except for portions of the Cascades.
However, precip chances will increase again Sunday night.
Today is definitely the coldest day of the next couple. Highs will
mainly be in the 20s, but some locations will struggle to break
20. On average, highs will be a couple of degrees warmer on
Saturday, then by Sunday about 3-5 degrees warmer on average with
many areas, especially across central Oregon and even portions of
the Basin approaching freezing. Overnight lows will be in the
single digits and teens.
LONG TERM...
MONDAY THROUGH FRIDAY...The extended period begins in
the midst of an incoming system set to bring another bout of
widespread snowfall to the area, especially for the Cascades and
eastern mountains. Low level snow will occur initially in the
morning hours before transitioning to more of a wintry mix as warmer
air pushes onshore associated with a warm front. The bulk of precip
occurs early Monday morning as mountain upslope snowfall is set to
linger into Tuesday before eventually tapering off late Tuesday for
the OR Cascades, and early Wednesday for the WA Cascades and eastern
mountains. The associated cold front moves through Monday night into
Tuesday, keeping chilly temps overnight before the offshore ridge
builds to increase high temps back into the low-40s by Tuesday and
lows in the upper-20s in the Basin.
Guidance is suggesting that the upper ridge offshore will infiltrate
into CA near the Bay Area and continue northeast, influencing our
region and allowing for conditions to dry out in anticipation of the
next system. Models are in good agreement with this next system that
is poised to move in early Thursday morning. The concern with this
system is that models have picked up on the persistent NW flow
becoming more westerly/south-southwesterly associated with
Wednesday's transient ridge, bringing in a more moist, Pacific
airmass that may keep snow chances across Central and South OR. PoP
chances increasing in intensity and becoming more widespread across
our area into Friday and potentially even into the weekend for our
mountain areas. Current confidence is leaning more toward the GFS
outcome when observing the ensemble clusters, which highlights a
significant southerly wind component coupled with onshore flow which
hints at additional moisture influx that could result in a wetter
system that sticks around our area into Saturday. Stay Tuned.
Temperatures continue to increase slightly through the extended
period, as late workweek highs stay in the mid-40s for the Basin and
mid-30s in the mountains. 75
AVIATION...
12Z TAFs...Variable conditions currently across all sites as
conditions degrade through the period. LIFR conditions expected
between 15-17Z as cigs drop to 005-009 and vsbys drop below 1SM
except for YKM where 1 1/2SM is expected. DLS will experience this
closer to 22Z, with cigs of 3/4SM. Periods of light snow will
continue through the period, and should be increasing in intensity
and PoP chances toward the end of the period as the next system
bears down on the PacNW. Winds should stay relatively light, with
PSC being the highest with 10kt northwest winds until 18Z. 75
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 18 13 21 11 / 60 80 90 30
ALW 22 17 25 16 / 60 70 80 30
PSC 25 19 29 15 / 50 70 80 30
YKM 23 17 27 14 / 40 80 80 30
HRI 24 17 26 15 / 60 90 90 30
ELN 22 16 27 14 / 30 70 60 20
RDM 24 11 27 10 / 40 80 80 20
LGD 23 18 25 13 / 60 80 80 20
GCD 32 25 33 17 / 50 90 90 30
DLS 24 18 27 18 / 70 90 90 40
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Winter Storm Warning until 4 PM PST Saturday for ORZ041-044-049-
502-503-507>511.
Winter Weather Advisory until 4 PM PST Saturday for ORZ505-506.
Winter Weather Advisory until 10 PM PST this evening for ORZ050.
WA...Winter Storm Warning until 4 PM PST Saturday for WAZ024-029-030-
520.
Winter Weather Advisory until 4 PM PST Saturday for WAZ521.
Winter Weather Advisory from 4 PM this afternoon to 4 PM PST
Saturday for WAZ026>028.
&&
MORNING UPDATE...82PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
718 AM PST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0950 PM HEAVY SNOW 5 S PENDLETON 45.60N 118.82W
02/11/2021 E4.0 INCH UMATILLA OR DEPT OF HIGHWAYS
4 INCHES OF NEW SNOW SINCE 933 AM. ELEVATION 1450 FEET.
ODOT REPORT.
&&
JASPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
724 AM PST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0305 AM HEAVY SNOW 9 S HARDMAN 45.04N 119.68W
02/12/2021 E7.0 INCH MORROW OR DEPT OF HIGHWAYS
7 INCHES OF NEW SNOW IN 24 HOURS. ODOT REPORT. ELEVATION
4300 FEET.
&&
JASPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
810 AM PST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0309 AM HEAVY SNOW 9 ENE GATEWAY 44.84N 120.93W
02/12/2021 E4.0 INCH WASCO OR DEPT OF HIGHWAYS
4 INCHES OF NEW SNOW SINCE 7 PM. ODOT REPORT. ELEVATION
2020 FEET.
&&
JASPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
812 AM PST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0636 AM HEAVY SNOW SHANIKO 45.00N 120.75W
02/12/2021 E4.0 INCH WASCO OR DEPT OF HIGHWAYS
4 INCHES OF NEW SNOW SINCE MIDNIGHT. ODOT REPORT.
ELEVATION 3300 FEET.
&&
JASPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
814 AM PST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0800 AM HEAVY SNOW 4 ESE PILOT ROCK 45.46N 118.75W
02/12/2021 M4.0 INCH UMATILLA OR TRAINED SPOTTER
7 INCHES OF NEW SNOW IN PAST 24 HOURS. ELEVATION 1900
FEET.
&&
JASPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
828 AM PST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0820 AM HEAVY SNOW 5 ENE APPLETON 45.85N 121.18W
02/12/2021 M10.0 INCH KLICKITAT WA TRAINED SPOTTER
10 INCHES OF NEW SNOW IN PAST 24 HOURS. ELEVATION 2100
FEET.
&&
JASThe national radar mosaic for the moment the first event began.
2 heavy snow. Local standard time, as filed.
A Cocorahs observer in SSE Prosser, WA measured 10.5 inches of snowfall in a 24 hour period ending at 9:30am PST on Feb. 13th. A social media report originating from Richland, WA measured 10 inches of snowfall at 9:05am on Feb. 13th.
A social media report originating 5 miles ENE of Walla Walla, WA estimated 8.5 inches of snowfall over a 48 hour period ending at 10:21am PST on Feb. 13th. A local newspaper from Walla Walla, WA estimated 5 inches of snowfall in a 24 hour period ending at 2:00pm PST on Feb. 12th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2021Every state in 2021This day in weather historyWarnings in Washington, February 2021
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: 935144, 935154.