A deep low off the coast of Oregon spread heavy snow across Southeast Oregon and Southwest Idaho over a 2 day period.
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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 BOI wrote it up.
A deep low off the coast of Oregon spread heavy snow across Southeast Oregon and Southwest Idaho over a 2 day period.
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 Boise, ID wrote its last area forecast discussion before the first event at Feb 12, 9:34 AM MST, 1 hour 26 minutes earlier.
Area Forecast Discussion
National Weather Service Boise ID
934 AM MST Fri Feb 12 2021
.DISCUSSION...Snow accumulated up to 3 inches overnight in parts
of the Treasure Valley with nighttime temperatures 2 to 4 degrees
lower than expected. That storm has now moved east of our CWA
with only flurries left behind. The next Pacific storm, currently
off the northwest coast, will be wetter and with more snow.
Winter Weather Advisories are currently in effect late tonight
and Saturday for eastern Oregon and southwest Idaho (except the
mountains north of the Snake Basin). Latest models now suggest
upgrading the advisories to Winter Storm Warnings for heavy snow
in eastern Oregon (except the south where rain is more likely),
and western Idaho including the Treasure Valley, and also in the
Idaho mountains north of the Snake Basin. NBM shows a chance of
freezing rain at Burns/OR overnight with above-freezing moist air
moving over sub-freezing surface air. Other models see it
differently there: GFS indicates rain (which we doubt), and NAM
indicates several inches of snow. Forecast changes and upgraded
Winter Weather products will be available for the afternoon
package.
Partial clearing and colder weather is expected Saturday night,
and Sunday also looks dry, but another Pacific storm will bring
more snow Sunday night and Monday.
&&
.AVIATION...MVFR to LIFR conditions due to low clouds and snow
will continue through the afternoon and the overnight period with
mountain obscurations. Isolated pockets of VFR as the region is
between systems today, but the next system will arrive this
evening. Surface winds: Variable less than 10 kts, becoming west
to northwest 10 to 20 kts after 12/18z. Wind decreasing after
sunset. Winds aloft at 10kft MSL: WNW 30 to 40 kts, then
increasing to 40 to 50 kts after 13/18z.
Weekend Outlook...MVFR to IFR conditions with gusty winds Saturday
as another storm system arrives. This system will bring
widespread snow across the entire region tonight through Saturday.
A lull in activity is anticipated Sunday, with a return of
snowfall Sunday night. Periods of mountain obscuration will
continue.
&&
.PREV DISCUSSION...
SHORT TERM...Today through Sunday night...Snow continues across
the forecast area this morning, though models continue to indicate
a lull in snowfall across the Treasure Valley starting within the
next couple hours. Mountain snow remains favored through the day.
Another surge of moisture late this afternoon / early this evening
will bring a return of snowfall across the valley locations. The
focus of moisture will shift to the southwestern half of the
forecast area this evening and through Saturday with additional
Winter Weather Advisories in place. Details regarding timing and
intensity can be seen in related products. The central Idaho
mountains continue to be monitored as models have bumped up
snowfall for this upcoming system. With other Advisories
currently in place, will have the next shift reevaluate their
status. Snowfall coverage will be less on Sunday, though some
pockets of snowfall will remain. Models then continue to indicate
another stronger push of moisture entering eastern Oregon later
Sunday night, with precipitation spreading east through the
overnight hours. Snow levels keep either snow or a rain-snow mix
across the area through the forecast period. Gusty winds will
also be possible with the Saturday system, especially south of the
Snake River Plain. Temperatures through the forecast period will
remain 5 to 15 degrees below normal, with the coolest temperatures
expected on Sunday.
LONG TERM...Monday through Friday...Active weather pattern will
continue through the extended period as a couple more systems more
through. One system will continue widespread precipitation across
Southwest Idaho through Monday afternoon. Early to mid-morning
snowfall remains possible across the Treasure Valley for Monday
though it may change into a mix of rain/snow by afternoon as
temperatures warm behind a warm front. Lingering snow is possible
Tuesday as a northwest flow aloft continues over the region. A
brief upper ridge axis will move over the area Wednesday ahead of
another upper low approaching the Pacific Northwest Wednesday
evening. That system will have a southwest flow aloft out ahead
of it which could allow the valleys to warm for a threat of rain
as mountains remaining as snow. There remains a lot of uncertainty
with how much cold air can remain in the valleys through the
week. Temperatures will generally remain 5 to 10 degrees below
normal through the forecast period.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 5 PM MST this afternoon
IDZ011-013-033.
Winter Weather Advisory from 11 PM this evening to 11 PM MST
Saturday IDZ012-014>016-029-030-033.
OR...Winter Weather Advisory until 4 PM PST this afternoon ORZ062.
Winter Weather Advisory from 11 PM MST /10 PM PST/ this evening
to 11 PM MST /10 PM PST/ Saturday ORZ062>064.
Winter Weather Advisory from 10 PM this evening to 10 AM PST
Saturday ORZ061.
&&
www.weather.gov/Boise
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DISCUSSION...LC
AVIATION.....CR
PREV SHORT TERM...KB
PREV LONG TERM....JDSPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOISE ID
948 AM MST FRI FEB 12 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0923 AM SNOW BOISE 43.61N 116.23W
02/12/2021 M2.5 INCH ADA ID NWS EMPLOYEE
2.5 INCHES OF SNOW AT THE NWS OFFICE AS OF 9AM.
0923 AM SNOW BOGUS BASIN SKI AREA 43.76N 116.10W
02/12/2021 E4.0 INCH BOISE ID PUBLIC
4.0 INCHES OF SNOW AT THE BOGUS BASIN SKI RESORT WEBCAMS.
0923 AM SNOW MCCALL 44.91N 116.11W
02/12/2021 E4.0 INCH VALLEY ID DEPT OF HIGHWAYS
4.0 INCHES VIA MCCALL WEBCAM.
0923 AM SNOW BRUNDAGE SKI AREA 45.00N 116.16W
02/12/2021 E3.0 INCH ADAMS ID PUBLIC
3.0 INCHES VIA WEBCAM.
0923 AM SNOW MERIDIAN 43.61N 116.40W
02/12/2021 M2.8 INCH ADA ID NWS EMPLOYEE
0923 AM SNOW TAMARACK 44.95N 116.37W
02/12/2021 E4.0 INCH ADAMS ID PUBLIC
4.0 INCHES VIA WEBCAMS.
&&
CREDMANThe national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
The COOP observer at Halfway reported 9 inches of new snow and reports were received from the public of 8 to 12 inches of snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2021Every state in 2021This day in weather historyWarnings in Oregon, 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: 945795.