A major winter storm brought periods of moderate to heavy snowfall and gusty northwest winds to 45 mph. Snowfall amounts were mainly in the 6 to 12 inch range.
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 BYZ wrote it up.
A major winter storm brought periods of moderate to heavy snowfall and gusty northwest winds to 45 mph. Snowfall amounts were mainly in the 6 to 12 inch range. In addition, surface observations showed prolonged reductions in visibilities below 1 mile. Interstate 90 was closed from Sheridan to Buffalo for a prolonged period of time. In addition, schools instituted virtual learning and the Wyoming Department of Transportation urged no unnecessary travel.
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 Billings, MT wrote its last area forecast discussion before the first event at Dec 12, 3:36 AM MST, 5 hours 24 minutes earlier.
Area Forecast Discussion
National Weather Service Billings MT
336 AM MST Mon Dec 12 2022
.DISCUSSION...
Today through Tuesday night...
The upper low that will be impacting the region through at least
the middle of this week was situated over northeastern Nevada
early this morning. Water vapor satellite imagery showed a steady stream
of moisture advecting north into the region. A cold front was
pushing south through the area overnight. Snow will spread into
the western and central areas through the morning hours, becoming
more widespread this afternoon and evening as the lower levels
moisten up and large scale ascent increases. Snow will increase
over southeast Montana overnight as the upper low shifts east
towards the central Plains, and moisture originating from the
Gulf of Mexico wraps around the low into the region. With decent
moisture, instability, upslope flow and a favorable temperature
profile through the dendritic growth zone, snowfall rates will be
increasing by the afternoon and evening. Snowfall amounts from
today through tonight will range from 2 to 4 inches, with the
greatest totals from Rosebud County and areas west.
Heading into Tuesday, the greatest impacts continue to be over
southeast Montana where snowfall will be greatest, and winds the
strongest. There will likely be a sharp gradient in snowfall over
central areas, as snowfall wraps back into the area and competes
with drier air to the northwest. Northwest winds wrapping around
the low will likely gust towards 40 mph by Tuesday afternoon over
the far southeast. The combination of snow and wind will create
near blizzard to blizzard conditions with significant impacts and
possible road closures, especially the closer you get to the
Dakotas and northeastern Wyoming. Snowfall amounts Tuesday through
Tuesday night are forecast to range from 6 to 10 inches from Big
Horn County and areas east (NBM probabilities of 6+ inches is 60
to 80 percent), with a quick decrease in snowfall the farther
west you go. Central areas, including Billings have the greatest
uncertainty with regards to snowfall totals during this timeframe.
Have gone ahead and upgraded the Winter Storm Watch over southeast
Montana to Winter Storm Warnings, with Blizzard Warnings for
Powder River and Carter counties, where conditions are forecast to
be worst. The remainder of the winter weather highlites continue
to be in good shape and will not make any changes at this time.
Periods of snowfall will continue to affect the area Wednesday and
Thursday. Information on this time period can be found in the
extended discussion below. STP
Wednesday through Sunday...
Wednesday into Wednesday night, the upper low will move eastward
from Nebraska to Iowa. This pattern will facilitate additional
snowfall in the form of a steady snow over southeast MT and north
central WY and periods of snow over south central MT. There could
well be periods of dry weather over south central MT on
Wednesday. A disturbance rotating around the upper low will then
cause a period of light snow over south central MT from Wednesday
afternoon into the night. Snow accumulation on Wednesday will be 1
to 5 inches over north central WY and southeast MT east of
Billings, with less than an inch elsewhere. Additional
accumulation Wednesday night is similar with 1-4 inches over
southeast MT, 1-2 inches over Sheridan County, and less than an
inch elsewhere. For the 24 hour period spanning Wednesday and
Wednesday night, the Weather Prediction Center is highlighting a
70% chance of at least 4 inches of snow over southeast MT.
Thursday, the upper low will continue to move eastward with more
light, steady snow over southeast MT. Another disturbance will
move south-southeastward Thursday afternoon into the night and
bring another round of light snow to south central-southeast MT
and north central WY.
From Tuesday through Thursday, total snow accumulation will range
from less than an inch northwest of Billings to over a foot over
southeast Montana and Sheridan County, Wyoming.
Friday into Friday night, upper ridging will move into the region
and dominate the weather with dry conditions. An isolated snow
shower is possible (20% chance) but any snow accumulation would be
minimal.
Through Friday, windy conditions over southeast MT-north central
WY will cause blowing and drifting snow. This is an added hazard
to the heavy accumulation expected. Even though snow should stop
falling on Friday, there likely will be more travel difficulties
in this area from the blowing and drifting snow.
Saturday into Sunday, different model solutions emerge with regard
to an upper low: ECMWF group favors a deep upper low closer to MT
but the GFS and Canadian groups favor a position farther east.
Models do generally agree on a cold front crossing our area
Saturday that brings temperatures down several degrees for Sunday.
The duration of the cold air then becomes uncertain, but a cold
snap is possible early next week. In addition, there can be
periods of light snow but the air will be dry so accumulation
will be limited.
High temperatures will generally be in the teens and 20s Wednesday
through Saturday then single digits and teens Sunday. RMS
&&
.AVIATION...
VFR will prevail for most of the area early this morning. There
will be patchy fog near KMLS, KBHK and Ekalaka this morning.
Conditions will deteriorate to MVFR-LIFR over south central MT
and north central WY after 12z today as the ceiling and visibility
decrease with light to moderate snow moving in. By tonight the
entire area will have light-moderate snow with MVFR-LIFR
conditions. Mountains will be obscured through the TAF period. RMS
&&
.PRELIMINARY POINT TEMP/POPS...
Tdy Tue Wed Thu Fri Sat Sun
-------------------------------------------------------
BIL 023 012/022 015/028 017/028 013/024 008/021 001/013
8/S 88/S 66/S 43/S 11/Q 12/S 22/S
LVM 025 011/026 014/027 014/027 010/024 008/025 003/021
8/S 44/S 33/S 21/Q 10/Q 12/S 21/B
HDN 021 009/019 011/023 013/025 008/022 002/019 906/010
7/S 99/S 88/S 74/S 22/S 12/S 22/S
MLS 021 009/016 011/018 012/019 008/015 000/013 906/005
2/S 89/S 99/S 84/S 22/S 11/B 11/B
4BQ 023 010/017 011/020 014/022 010/018 003/018 903/011
2/S 8+/S +9/S 85/S 22/S 11/B 11/B
BHK 020 011/018 012/019 009/016 006/013 000/011 905/005
2/S 7+/S +9/S 84/S 21/Q 11/B 10/B
SHR 025 007/019 010/023 012/025 010/022 003/023 903/016
5/S 9+/S 98/S 75/S 32/S 12/S 22/S
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory in effect until 5 AM MST Tuesday FOR
ZONES 29-34-40-42-56-63>66-139-141-170-172-173-228-235.
Winter Storm Warning in effect from 11 AM this morning to 5
AM MST Thursday FOR ZONES 30-57-138-169-171.
Winter Storm Warning in effect from 11 PM this evening to 5
AM MST Thursday FOR ZONES 31>33-58.
Blizzard Warning in effect from 11 PM this evening to 5 AM
MST Thursday FOR ZONES 36-37.
WY...Winter Storm Warning in effect from 11 AM this morning to 5
AM MST Thursday FOR ZONES 198-199.
&&
weather.gov/billingsThe national radar mosaic for the moment the first event began.
2 winter storm. Local standard time, as filed.
Snowfall of 5 to 13 inches, along with poor road conditions, were reported across the area.
Snowfall of 8 to 12 inches was reported across the area. In addition, U.S. 212 and Interstate 90 were closed, along with area schools.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2022Every state in 2022This day in weather historyWarnings in Wyoming, December 2022
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: 1066545, 1066546.