A low pressure moving across the Upper Great Lakes brought moderate to heavy lake enhanced snow to west half portions of Upper Michigan from the afternoon of the 20th into the morning of the 21st.
Every event with a place to put it; 5 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 MQT wrote it up.
A low pressure moving across the Upper Great Lakes brought moderate to heavy lake enhanced snow to west half portions of Upper Michigan from the afternoon of the 20th into the morning of the 21st.
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 Marquette, MI wrote its last area forecast discussion before the first event at Feb 20, 11:51 AM CST, 1 hour 9 minutes earlier.
Area Forecast Discussion
National Weather Service Marquette MI
1251 PM EST Mon Feb 20 2023
.SHORT TERM...(Today)
Issued at 344 AM EST MON FEB 20 2023
Water vapor imagery and RAP analysis show one shortwave trough
moving east through Ontario early this morning which along with CAA
behind its attendant sfc low and cold front has resulted in some
fluffy LES accumulation from last evening into the overnight hours.
A second clipper shortwave upstream over southern Saskatchewan and
the nw North Dakota border will be the next weather producer for
Upper Michigan as it moves across the area tonight. Widespread
advisory criteria snowfall is expected with this clipper system
across much of the northern and eastern tiers of the U.P. beginning
this afternoon into Tuesday morning.
IR satellite, radar imagery and sfc obs indicate light northerly
flow LES still lingers early this morning over mainly the north
central UP. However, radar reflectivities have definitely been
diminishing the last couple hours and snowflake size is much smaller
so not expecting much additional accumulation, maybe a tenth or two
before LES ends later this morning as a sfc ridge builds in from the
west.
Focus then shifts to the clipper shortwave/system approaching from
the High Plains. Models in fairly good agreement that this shortwave
and its attendant sfc low will track east through central MN into
far NW WI this afternoon into early evening and then into central
and eastern Upper Mi later tonight. Model qpf fields and soundings
show the onset of the snow from this system holding off until
afternoon, but then the column saturates fairly quickly with
moderate to strong isentropic ascent/q-vect convergence and upper
diffluence ahead of the shortwave. Using the mixing ratio method at
the 280K sfc, mixing ratios up to 2g/kg advecting over the area
should result in a fairly widespread 1-2 inches across much of the
western half of the UP this afternoon from 18-00Z. Amounts across
the higher terrain of the Keweenaw and Copper County could be
boosted into the 3-4 inch range though due to a combination of
enhanced fgen and lake enhancement. The east half will probably only
see an inch or less of snow in the afternoon (18-00Z time frame), but
they will quickly get into high-end advisory amounts tonight in some
counties due to lake enhancement potential off Lake Michigan. Good
model omega/lift through the DGZ as noted on the fcst soundings could
also boost snow ratios and thus snow amounts higher than expected
this afternoon.
Under mostly cloudy skies, temps early this morning in the teens to
lower 20s will rise into the mid 20s to lower 30s this afternoon,
warmest south central.
.LONG TERM...(Tonight through Sunday)
Issued at 417 AM EST MON FEB 20 2023
Key Messages:
-High Res models have significantly increased snowfall totals over
the UP this afternoon and tonight. Therefore widespread Winter
Weather Advisories have been issued for much of the CWA, with some
low-end warnings possibly being needed over the Keweenaw Peninsula
and east tonight.
-The mid-week system is expected to bring some significant lake-
enhanced snowfall and possibly some blowing snow concerns across the
region, particularly over the NE snow belts.
-The active weather pattern continues through this weekend.
A robust and very moist Clipper low moves through Upper MI tonight,
bringing some moderate to heavy snowfall rates across the area
early. Some hi-res models have significantly increased snow totals
across the area, as this suite of guidance is likely picking up on
the mini-TROWAL of the Clipper bringing higher snowfall rates across
the northern half of the UP. In addition, CAMs highlight a strong
band of heavy snowfall moving from west to east across the UP
tonight, with the band intensifying over the east due to lake
enhancement off of Lake MI around and after midnight tonight.
Therefore, due to the increased snowfall amounts and band of heavy
snowfall moving through the area early tonight, a Winter Weather
Advisory has been issued for all the UP save for Iron, Dickinson,
and Menominee counties (although Iron may need to be included too as
it looks to reach marginal Winter Weather Advisory criteria). With
robust atmospheric lift over the west and lake enhancement over the
east and Keweenaw, snowfall rates over these spots may exceed 1
in/hr for a few hours, particularly over the lake enhanced areas; a
low-end Winter Storm Warning may need to be issued for the Keweenaw
and east in the future. As the low begins to head into Canada early
Tuesday morning, expect one last band of heavy lake enhanced
snowfall to move over the N snow belts around the time of the
morning commute. Overall, thinking the higher terrain over the north
central and west as well as the east downwind of Lake MI could see 6
to 10 inches of fluffy snowfall between early this afternoon and
dawn Tuesday morning; it is plausible that some localized spots
could see up to a foot of snow. Meanwhile, the interior west and
north central (outside the higher elevations) could see 3 to 6
inches, whereas the south central may see less than an inch to 3
inches. To be honest, I'm a little nervous about how high the snow
totals are given that the QPF may be a bit too high, particularly
over the east late tonight; I'm kinda expecting closer to 6 to 8
inches at most over the west and east given most model guidance
hints at lower QPF totals. However, given sufficient moisture flux
over the Great Lakes, the mini-TROWAL projected over the northern
half of the UP, and upslope flow over the east and Keweenaw (and
N/NW snow belts on the backside of the low late tonight into Tuesday
morning), it is still possible that these higher totals will be
achieved; indeed the HIRES-ARW, the NAMDNG, and the HREF all hit on
this. Therefore, while snow totals could be lower than what is
currently predicted, they may also be achieved, with some spots
possibly even locally overachieving. As we head into Tuesday, expect
the transition to pure LES over the NW snow belts, with the snowfall
dwindling throughout the day as weak ridging builds into the region.
The next weather of note starts as we head into Tuesday night. Model
guidance shows a significant trof developing over the Intermountain
West Tuesday. This trof is expected to eject two shortwave lows over
the Plains, with the first one beginning to lift Tuesday
night/Wednesday morning. As this occurs, we could see some light
system snowfall move across the area late Tuesday night into
possibly Wednesday morning before dry air at the mid-levels and sfc
cut-off any additional snow. As the first shortwave low weakens as
it lifts into the Lower Great Lakes Wednesday evening, a second,
more robust shortwave low lifts from the Central Plains towards
Lower MI Wednesday into Thursday. As it does so, expect some
snowfall to move into the area from WI; some lake enhancement looks
possible over the NE snow belts as this occurs. We could see some
significant snowfall over the NE snow belts Wednesday night into
Thursday, as delta-Ts near 20C, high snow ratios, and localized
upslope flow could produce intense snowfall rates. The Euro EFI
supports this line of thinking by putting most of our area in the 0
shift to tails and west in 1 shift to tails. In addition,
anomalously high NE'rly winds could bring snow bands much further
inland, in addition to creating blowing snow concerns across much of
the area. The only thing that may hinder snow totals with this
system is that model skew-Ts show a significant dry layer at around
5 kft Wednesday/Wednesday night. However, with sufficient lift and
moisture in the mid levels due to the TROWAL of this second low
getting moisture from the TROWAL of the first shortwave low (in
addition to some Gulf of Mexico moisture sneaking in from the warm
sector), I wonder if this dry layer will be overcome fairly quickly
by Wednesday night. Whether this is overcome sooner or not will
likely depend the strength of the weak localized ridge over us in
the lower levels of the atmosphere during the middle of this week as
the second shortwave low approaches. Ultimately, the greatest
snowfall amounts and rates, as well as the highest winds, look to
happen Thursday as the TROWAL of the second low finally gets
overhead. As the low quickly moves into southern Canada Thursday
evening, expect the winds to veer with time, with the transition to
LES occurring during the overnight hours. Expect the LES to die-down
Friday as weak ridging once again moves back over the area.
The active weather pattern continues into this weekend, as another
shortwave low brings some WAA back across the area. This is looking
to bring additional snowfall across the area, particularly over the
east half. Behind it, another weak shortwave from Canada looks to
bring a strong shot of cold air back across the area next Sunday,
kicking off some LES over the NW snow belts. Additional shortwave
lows look to impact the area as we head into next week, with the
active weather pattern looking to continue as we head into March.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1250 PM EST MON FEB 20 2023
Conditions will deteriorate from VFR to IFR through the afternoon
from west to east as a clipper system approaches the area. IFR
conditions will continue through the night in light snow and
eventually blowing snow as winds turn northwesterly behind the low
and become quite gusty for a few hours. Conditions will begin to
improve by mid/late morning Tuesday.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 435 AM EST MON FEB 20 2023
Light winds of 20 knots or less this morning become SE'rly winds of
20 to 30 knots across Lake Superior this afternoon and evening ahead
of an approaching Clipper low moving towards Upper MI. As the low
travels through Upper MI tonight, expect the winds over Lake
Superior to back with time, with a band of 35 to 40 knot N'rly gales
moving from west to east across the lake tonight through Tuesday
morning. With the strong winds and CAA expected behind the Clipper
low, Gale and Heavy Freezing Spray Warnings have been issued across
most of the lake from tonight to Tuesday afternoon. As the Clipper
low leaves into Canada Tuesday, expect the winds to die down
quickly, becoming 20 knots or less again by early Tuesday evening.
However, as a robust shortwave low lifts from the Central Plains
towards Lower MI Wednesday into Thursday, expect NE'rly winds to
pick up over Lake Superior during the middle of this week. With the
cold air aloft hanging in place, expect the higher wind speeds to
bring heavy freezing spray across the area Wednesday; the heavy
freezing spray is expected to remain across the lake until Friday
morning. Expect the highest NE'rly winds Thursday as the TROWAL of
the low moves overhead, with gales of 40 to 45 knots expected across
the lake; a few storm force gusts up to 50 knots could be seen in
the far western lake Thursday. As the low continues into southern
Canada Thursday evening, expect the winds to back with time and
weaken, eventually becoming 20 knots or less again by Friday
morning.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Winter Weather Advisory until 7 AM EST Tuesday for MIZ001>004-
009-084.
Winter Weather Advisory from 4 PM this afternoon to 7 AM EST
Tuesday for MIZ005.
Winter Weather Advisory from 7 PM this evening to 7 AM EST
Tuesday for MIZ006-007-013-014-085.
Lake Superior...
Gale Warning from 1 AM to 1 PM EST Tuesday for LSZ245>251-
265>267.
Gale Warning from 10 PM this evening to 7 AM EST Tuesday for
LSZ240>244-263-264.
Heavy Freezing Spray Warning from 1 AM to 1 PM EST Tuesday for
LSZ240>251-263>267.
Lake Michigan...
Gale Warning from 1 AM to 1 PM EST Tuesday for LMZ248-250.
&&
SHORT TERM...Voss
LONG TERM...TAP
AVIATION...MZ
MARINE...TAPHazardous Weather Outlook...CORRECTED National Weather Service Marquette MI 532 AM EST Mon Feb 20 2023 MIZ001>007-009-010-013-014-084-085-211015- Keweenaw-Ontonagon-Northern Houghton-Baraga-Marquette-Alger-Luce- Gogebic-Iron-Delta-Southern Schoolcraft-Southern Houghton- Northern Schoolcraft- 532 AM EST Mon Feb 20 2023 /432 AM CST Mon Feb 20 2023/ This Hazardous Weather Outlook is for portions of central Upper Michigan and western Upper Michigan. .DAY ONE...Today and Tonight Moderate to at times heavy accumulating snowfall is possible from this afternoon into Tuesday morning. North winds gusting to 35 mph will also lower visibility in blowing snow. See the latest Winter Weather Message for additional details. Waves building near 7 feet could cause some minor beach erosion tonight from the Garden Peninsula to Seul Choix Point. Waves building near 14 feet could cause some minor beach erosion from Ontonagon up to the tip of the Keweenaw tonight and from Marquette to Shot Point Tuesday morning. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Moderate accumulating snowfall is possible Wednesday night through Thursday night across much of Upper Michigan. .SPOTTER INFORMATION STATEMENT... The need for weather spotter reports is not anticipated at this time. MIZ011-012-211015- Dickinson-Menominee- 432 AM CST Mon Feb 20 2023 This Hazardous Weather Outlook is for portions of central Upper Michigan. .DAY ONE...Today and Tonight Snowfall accumulation from 1 to locally 4 inches could cause some slippery travel this afternoon into tonight. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Moderate accumulating snowfall is possible Wednesday night through Thursday night across much of Upper Michigan. .SPOTTER INFORMATION STATEMENT... The need for weather spotter reports is not anticipated at this time. LSZ162-240>251-263>267-211015- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM-Saxon Harbor WI to Black River MI- Black River to Ontonagon MI- Ontonagon to Upper Entrance of Portage Canal MI- Upper Entrance of Portage Canal to Eagle River MI- Eagle River to Manitou Island MI- Manitou Island to Point Isabelle MI- Point Isabelle to Lower Entrance of Portage Canal MI- Lower Entrance of Portage Canal To Huron Islands MI Including Keweenaw and Huron Bays-Huron Islands to Marquette MI- Marquette to Munising MI-Munising to Grand Marais MI- Grand Marais to Whitefish Point MI- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- Lake Superior East of a line from Manitou Island to Marquette MI and West of a line from Grand Marais MI to the US/Canadian Border Beyond 5NM from shore- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 532 AM EST Mon Feb 20 2023 /432 AM CST Mon Feb 20 2023/ This Hazardous Weather Outlook is for portions of Central Lake Superior...Eastern Lake Superior and Western Lake Superior. .DAY ONE...Today and Tonight North to northwest gales of 35 to 40 knots and heavy freezing spray are expected late this evening into Tuesday morning across all but far western Lake Superior. See the latest Marine Weather Message and Open Lake Forecast for additional details. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday North gales of 35 to 40 knots will continue into Tuesday morning over the east half and heavy freezing spray will continue through Tuesday. See the latest Marine Weather Message and Open Lake Forecast for additional details. Northeast gales of 35 to 45 knots and heavy freezing spray are possible late Wednesday into Thursday. See the latest Open Lake Forecast for additional details. .SPOTTER INFORMATION STATEMENT... The need for weather spotter reports is not anticipated at this time. LMZ221-248-250-211015- Green Bay North of line from Cedar River MI to Rock Island Passage-Seul Choix Point to Point Detour MI- 5NM East of a line from Fairport MI to Rock Island Passage- 532 AM EST Mon Feb 20 2023 This Hazardous Weather Outlook is for portions of Northern Lake Michigan. .DAY ONE...Today and Tonight West to northwest gales to 35 knots are expected late tonight. See the latest Marine Weather Message and Nearshore Marine Forecast for additional details. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Northwest gales to 35 knots will continue Tuesday morning. See the latest Marine Weather Message and Nearshore Marine Forecast for additional details. Northeast gales of 35 to 40 knots are possible Wednesday night into Thursday. .SPOTTER INFORMATION STATEMENT... The need for weather spotter reports is not anticipated at this time. Voss
The national radar mosaic for the moment the first event began.
4 winter weather, 1 winter storm. Local standard time, as filed.
Observers in Ironwood measured between 9 and 12 inches of lake enhanced snow over an approximate 18-hour period.
Observers measured a widespread 5 to 8 inches of lake enhanced snow over an approximate 18-hour period.
Observers measured a widespread 4 to 7 inches of lake enhanced snow across the higher terrain of Baraga County over an approximate 18-hour period.
Moderate lake effect snow totals over an approximate 18-hour period included 6.2 inches at Bergland and 5.4 inches eight miles north of Mass City.
An estimated 4 to 7 inches of lake enhanced snow fell over an approximate 18-hour period.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Michigan in 2023Every state in 2023This day in weather historyWarnings in Michigan, February 2023
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: 1082083, 1082084, 1082087, 1082103, 1082112.