A strong fall storm system affected much of the Northland on November 11 into the 12th. Warm temperatures ahead of an area of low pressure led to a rain event across the southern part of the area while colder air moving in from the north led to a changeover to snow from the International Falls area southward into the Iron Range area earlier than forecast.
Every event with a place to put it; 3 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 DLH wrote it up.
A strong fall storm system affected much of the Northland on November 11 into the 12th. Warm temperatures ahead of an area of low pressure led to a rain event across the southern part of the area while colder air moving in from the north led to a changeover to snow from the International Falls area southward into the Iron Range area earlier than forecast. This lead to snowfall of 6 to 8 inches from southern Koochiching County into central St. Louis County where a colder pocket of air moved in and kept snow going earlier and longer than anticipated. The snow along the Iron Range led to snow and ice covered roads and multiple wrecks. One wreck near Gilbert resulted in two fatalities.
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 Duluth, MN wrote its last area forecast discussion before the first event at Nov 10, 10:28 PM CST, 5 hours 32 minutes earlier.
Area Forecast Discussion
National Weather Service Duluth MN
1028 PM CST Wed Nov 10 2021
.DISCUSSION...(This evening through Tuesday)
Issued at 438 PM CST Wed Nov 10 2021
Summary...Our first winter storm system will move through the
region tonight through Friday night, bringing a mix of rain and
snow with some significant snowfall accumulations and strong winds
to the area. Another round of light snow/rain is expected
Saturday night into Sunday. The forecast remains cold but becomes
dry for the rest of Sunday into Monday, though lake effect showers
will be possible. A gradual warm-up can be expected for the
middle of next week, but with some precipitation chances as well.
The main focus of this forecast is the storm system due to move
through the area tonight through Friday night. Tonight a strong
band of warm air advection, isentropic lift and frontogenesis is
going to lift up into the region, then continue to lift northeast
on Thursday. Plenty of warm air surging into the area from the
south will keep precipitation types tonight for most of the area
all rain, though parts of northern Minnesota will see a mix or
even all snow, overnight and Thursday morning, with a few inches
of snow accumulation expected for Itasca, Koochiching, and the
Arrowhead. This will be wet, heavy snow, and combined with the
warm ground, it is going to be difficult to get the snow to pile
up except on grassy or elevated surfaces. Together with compaction
and other melting going on, have reduced snowfall amounts from
what guidance would imply to a certain extent. Temperatures
overnight to only dip below freezing for parts of northern
Minnesota. Thursday, temperatures should get above freezing
everywhere, and together with the weak solar insolation this time
of year, most of the daytime precipitation will be either rain or
snow that melts once it hits the ground. The exception will be as
the cold air begins to push into the area from the west, causing
the temperature column and surface temperatures to begin falling,
and I expect snow to begin accumulating on grassy surfaces by mid-
late afternoon Thursday for north central Minnesota. Synoptically,
the surface low crosses the eastern forecast area during the day
on Thursday and we get into the TROWAL/CAA areas of the storm,
which should produce a decent frontogenesis band of wrap-around
precipitation that slowly slides into the area from the northwest
during the day, then slowly weakening and pulling northeast wind
time Thursday night and Friday. This precipitation is going to
have a good pool of cold air to tap into aloft, and with colder
surface temperatures sliding into the area Thursday afternoon,
most precipitation will switch over to snow for Thursday night and
Friday morning. The best lift and thermal parameters Thursday
night remain over far northern Minnesota where it appears we may
get 3 to 6 inches of snow around International Falls and
surrounding areas. There is still considerable uncertainty in how
much snow is going to accumulate Thursday afternoon through Friday
morning, with ground and air temperature changes, and the
position of the heavier precipitation band. For now we have issued
a winter storm watch for Thursday afternoon through Friday
morning, and later shifts will have to take another look at it, as
what happens tonight will affect what happens tomorrow night.
Behind this potent fall storm, Friday through Sunday we will
still be under the influence of cyclonic flow and a cold pool
aloft, which will produce shower chances as well as some lake
effect snow chances along the South Shore through Sunday morning.
A shortwave moves through the region late Saturday and early
Sunday, which may bring another chance for accumulating snow to
parts of the area. The track of this wave has been shifting on the
last few model runs, so we will have to wait for that to
stabilize before we can determine more details.
We can expect a bit of a warm-up starting Monday and continuing
through at least mid week, as the strong upper level trough
finally shifts east and allows ridging and warm air advection to
push into the area. With the baroclinic zone nearby, we can expect
some weak shortwave to move through the upper level flow that may
bring us some small precipitation chances next week, but no
significant system are currently in the forecast through next
Wednesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 522 PM CST Wed Nov 10 2021
A messy forecast this TAF set with poor flying conditions expected
the next 24 hours as a low pressure system moves toward the region.
Current VFR conditions to slowly deteriorate this evening, with an
area of rain and predominantly IFR conditions spreading in from
south to north across the area through the TAF period. A few
locations may also receive snow, reducing conditions still further
to LIFR. Strong southeast winds aloft to produce LLWS this evening
for a few sites, though other sites may also be affected. Some
improvement in visibilities may be found after 16z Thursday, but
ceilings are likely to remain IFR.
&&
.MARINE...
Issued at 957 PM CST Wed Nov 10 2021
A Gale Warning is in effect for part of the North Shore zones and
the Outer Apostle Islands. There is a small possibility that the
Grand Marias to Grand Portage zone could see storm warning winds
tomorrow morning for a short time. However, given the uncertainty,
holding off on upgrading to a Storm Warning. A Small Craft
Advisory is in effect for the Twin Ports to Saxon Harbor. Winds
will be out of the east to northeast over Lake Superior.
Overnight, winds will continue to increase and peaking tomorrow
morning. There is some uncertainty as to whether or not the gale
winds will make it down to the twin ports so for now a Small Craft
Advisory will remain in effect for that portion of the Lake
Superior. As the surface low pressure moves northward into
southern Ontario the winds will shift around to the southwest by
tomorrow afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 36 43 29 37 / 100 100 50 60
INL 32 37 27 34 / 100 100 100 70
BRD 34 40 27 35 / 100 50 70 40
HYR 37 47 28 39 / 100 100 40 40
ASX 38 50 29 41 / 100 90 40 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...Winter Storm Watch from Thursday afternoon through Friday
morning for MNZ010-011-018.
LS...Small Craft Advisory until 9 PM CST Thursday for LSZ121-144>148.
Small Craft Advisory from noon to 9 PM CST Thursday for LSZ142-
143-150.
Gale Warning until noon CST Thursday for LSZ142-143-150.
Small Craft Advisory from 6 PM to 9 PM CST Thursday for LSZ140-
141.
Gale Warning until 6 PM CST Thursday for LSZ140-141.
&&
DISCUSSION...LE
AVIATION...LE
MARINE...KSEHazardous Weather Outlook National Weather Service Duluth MN 501 PM CST Wed Nov 10 2021 MNZ010>012-018>021-026-112315- Koochiching-North St. Louis-Northern Cook/Northern Lake- North Itasca-Central St. Louis-Southern Lake/North Shore- Southern Cook/North Shore-South Itasca- 501 PM CST Wed Nov 10 2021 This Hazardous Weather Outlook is for portions of northeast Minnesota. .DAY ONE...Tonight A wintry mix of rain and snow is expected to begin this evening, mainly over Koochiching County and spreading eastward into the Minnesota Arrowhead. Snowfall accumulations will generally be light, between 1 to 2 inches. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday The wintry mix will affect the remainder of the region Thursday, becoming all snow by Thursday evening and continue into Friday morning. At this time, the highest snow totals appear to be in Koochiching County, northern St. Louis and northern Itasca counties, where a Winter Storm Watch has been issued. Lake effect snow is possible in the northwest Wisconsin snow belt Friday night through Saturday. Another brief brush with snow is forecast Saturday and Sunday with some light accumulations possible. .SPOTTER INFORMATION STATEMENT... Snow spotters are requested to report their snowfall measurements to the National Weather Service. LSZ121-140>148-150-112315- Bayfield to Oak Point WI-Grand Portage to Grand Marais MN- Grand Marais to Taconite Harbor MN- Taconite Harbor to Silver Bay Harbor MN- Silver Bay Harbor to Two Harbors MN-Two Harbors to Duluth MN- Duluth MN to Port Wing WI-Port Wing to Sand Island WI- Sand Island to Bayfield WI-Oak Point to Saxon Harbor WI- Outer Apostle Islands Beyond 5 NM from Mainland- 501 PM CST Wed Nov 10 2021 This Hazardous Weather Outlook is for portions of Lake Superior and the Nearshore waters of western Lake Superior. .DAY ONE...Tonight Increasing easterly winds will gust to 35 to 45 knots tonight through Thursday morning, creating very hazardous conditions. Gale Warnings and Small Craft Advisories are in effect this afternoon and tonight. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Gale Warnings and Small Craft Advisories continue through Thursday, with the advisories continuing through the evening. Gusty winds return Friday and Friday night and may create hazardous conditions once again. MNZ025-033>038-WIZ001>004-006>009-112315- North Cass-South Cass-Crow Wing-Northern Aitkin-South Aitkin- Carlton/South St. Louis-Pine-Douglas-Bayfield-Ashland-Iron- Burnett-Washburn-Sawyer-Price- 501 PM CST Wed Nov 10 2021 This Hazardous Weather Outlook is for portions of northeast Minnesota and northwest Wisconsin. .DAY ONE...Tonight No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Lake effect snow is possible in the northwest Wisconsin snow belt Friday night through Saturday. Another brief brush with snow is forecast Saturday and Sunday with some light accumulations possible. .SPOTTER INFORMATION STATEMENT... Snow spotters are requested to report their snowfall measurements to the National Weather Service. JTS More information may be obtained at the following web address: http://www.weather.gov/duluth (all lower case)
The national radar mosaic for the moment the first event began.
3 heavy snow. Local standard time, as filed.
Heavier than expected snow was observed across the northern portion of St. Louis County with 6 to 8 inches being reported over a 24-hour period. This highest total was 8 inches near Celina.
A strong storm brought heavy snow to much of the county in a span of just over 12 hours. Snowfall totals of 6 to 8 inches were reported with the highest report being 8 inches near Big Falls.
Heavier than expected snow led to snow and ice covered roads along the Iron Range. This lead to a multi-vehicle accident near Gilbert that resulted in two fatalities (indirect) and at least two injuries (indirect) from one vehicle. The occupants of the other vehicles in the wreck were not injured or had non-life threatening injuries. Snowfall totals of 5 to 7 inches were reported along the Range with the highest report being 6.8 in Chisholm.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Heavy Snow, Central St. Louis | 2021-11-11 | 32 | Female | Vehicle/Towed Trailer | Indirect |
| Heavy Snow, Central St. Louis | 2021-11-11 | 11 | Male | Vehicle/Towed Trailer | Indirect |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2021Every state in 2021This day in weather historyWarnings in Minnesota, November 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: 993057, 993056, 993049.