Ice Storm in Michigan, February 21 to 22, 2022

Area Forecast Discussion
National Weather Service Gaylord MI
938 PM EST Mon Feb 21 2022

.UPDATE...
Issued at 920 PM EST Mon Feb 21 2022

Surface low taking shape over Missouri this evening, sliding
northeast over the next 24 hours along a stalled out frontal
boundary across the southern Great Lakes. Low level cold air has
become entrenched across much of northern Michigan with
temperatures ranging from the single digits over eastern upper to
the lower 20s closer to M-55. Precipitation will blossom across
northern Michigan over the next several hours as warm air aloft
slides over the top of the entrenched low level cold air. Our
current forecast thoughts on precipitation type haven't really
changed much, with mainly snow over eastern upper into the Tip of
the Mitt, mainly sleet closer to the M-32 corridor and mainly
freezing rain from M-72 southward.

Precipitation will come in two waves, with the first batch
tonight, and a second, more impressive batch of precipitation
later Tuesday morning into the afternoon hours as the surface low
draws closer. Overall, over the next 24 hours, several inches of
snow over eastern upper into the Tip of the Mitt (M-68 northward),
a few inches of sleet possible along the M-32 corridor, with ice
accumulations up to 0.25 inches (or more) from M-72 to M-55. All
in all, a real mess with poor travel conditions expected in many
parts of northern Michigan through Tuesday evening. No headline
changes at this time. It will be close as to whether
Gladwin/Arenac Counties need an upgrade to an ice storm warning -
depending on how much warm air gets into that area.

&&

.NEAR TERM...(Through Tonight)
Issued at 315 PM EST Mon Feb 21 2022

High Impact Weather Potential: Multi-day wintry mix begins. Snow,
sleet and freezing rain accumulation all likely.

Pattern Synopsis/Forecast: Large scale pattern early this afternoon
continues to feature a weakly positive tilt trough across the
western third of the country with generally zonal flow prevailing
east of the Rockies. 120+ kt northern jet streak lies from the
northern plains east into the Atlantic while southern jet is
stretched across the far southern plains into the lower Mississippi
Valley. This has set up a tight baroclinic zone from the northern
plains eastward through the upper Great Lakes into southern
Ontario/Quebec.

Isentropically driven band of snow across the Dakotas/MN earlier
this morning is now filling in as far east as the central UP.
Primary focus through tonight will revolve around that ongoing band
of snow north as it pushes toward eastern upper and well-advertised
developing/strengthening surface low across the central plains
that'll ride along a cold/stationary front draped from the mid-MS
Valley into the lower lakes. With the approach of this system, that
boundary will begin to lift north as warm front tonight, but will
likely remain well to the south of northern MI.

Primary Forecast Concerns: Precipitation type and amounts.

Clouds will continue to thicken and lower this afternoon as deeper
moisture/forcing spread into the area from the west and low-levels
continue to gradually saturate. As was alluded to above, light snow
already ongoing across central sections of the UP. Across northern
lower, certainly a different story as saturation is expected to take
much longer, but may moisten up enough above the boundary layer to
result in some nuisance freezing drizzle and/or flurries in spots
into this evening (already ongoing intermittently across the higher
terrain). It's not until late this evening when deep layer
saturation eventually occurs across northern lower, but as we wait
for this to occur, southwesterly return flow above the inversion
should help to bring an elevated warm nose into areas south of M-
32...most notably along/south of M-72.

Ultimately, still setting up for a messy forecast tonight. Current
trends still remain in favor of primarily all snow across eastern
upper and north of M-68 in the tip of the mitt. A transition to
snow/sleet/freezing rain south of there. Snow amounts through
tonight in the 1-3 inch range, highest across Chippewa County. Ice
accumulation on the order of around a tenth of an inch, or even a
touch more, especially along and south of M-72. Between M-68 and M-
72 likely to be the toughest call with a snow/sleet/freezing rain
mix in that corridor. Lesser snow/ice amounts, but even a couple
tenths of an inch of sleet can serious issues on roads. Of course,
this is just the start of long duration messy winter weather with
very changeable conditions through Tuesday night, particularly with
regard to ice/sleet accumulation. In coordination with the short-
term forecaster, will go ahead and issue a long duration Ice Storm
Warning for the M-72 and M-55 corridors with a Winter Weather
Advisory elsewhere. Certainly impacts to roads with hazardous travel
expected across the entirety of northern Michigan. Some tree
limb/power line damage not out of the question in ice storm warning
areas. &&

.SHORT TERM...(Tuesday through Thursday)
Issued at 315 PM EST Mon Feb 21 2022

High Impact Weather Potential: Continuation of tonight's
accumulating snow/sleet/freezing rain event...

Pattern Synopsis/Forecast:

Last 24-48 hours has seen ridging cross the Great Lakes behind a
departing shortwave. A niblet of energy crossed through northern
Michigan late yesterday...associated with a surface system that
tracked by to our northwest, which dragged a surface cold front
southward through the region. This surface front has stalled across
the MI/IN border this morning...with a tight baroclinic zone aloft
over the state (850mb temps on 12z/21 RAOBs range from +0C at DTX, -
5C at APX, and -19C at INL)...reinforced by cold advection
associated with am expansive 1040mb surface high centered in the
Canadian Prairie provinces, oozing eastward across Ontario to our
north...and warm, moist return flow off the Gulf, thanks to a
~1030mb surface high over the Carolinas. Above this...120+kt upper
level jet max resides more or less over the BCZ...with axis
stretching from the Arrowhead of Minnesota eastward toward Maine;
similarly strong subtropical jet resides across the southeastern
US...but do note some additional jet max energy rounding the base of
the troughing across the western US this morning...with a 140+kt jet
N-S oriented jet max just upstream, along the edge of ridging in the
Gulf of Alaska. Positively tilted long-wave trough axis aloft
stretches back into the western US, taking on a steeper tilt out
over the Rockies as northern stream energy dives southward along the
West Coast and a closed low off the coast of southern California
becomes absorbed into the flow...with additional northern stream
energy (extending from a sub-490dm 500mb closed low over Hudson Bay)
pivoting southward through the Canadian Prairies behind that cold
high pressure. Steeper tilt to troughing across the western US
results in an inflection point over the lee of the Rockies...where
general area of surface low pressure is beginning to develop across
eastern Colorado/western Kansas and Nebraska. Expansive area of
moisture aloft stretches across the Northern Plains and Upper
Midwest along the northern edge of the BCZ as warm, moist air rides
up over the developing frontal zone...with a little bit of
convection developing across the Gulf coast states this morning.

Going forward...will look for a wave to ride northeastward along the
baroclinic zone, crossing Michigan Tuesday into Tuesday night.
Baroclinic zone will remain SW-NE oriented...and shift slightly
further south...as positively tilted longwave troughing holds firm
across the CONUS Wednesday..However...will look for the sharp trough
axis across the western US to begin to eject eastward going into
Thursday...as another niblet of energy dives over the ridge into the
western US Thursday into Thursday night. Ejecting trough axis
crossing the center of the country should drive another round of
cyclogenesis...which has potential to impact parts of the Great
Lakes late in the period into the start of the long term.

Primary Forecast Concerns: Potential for breezier conditions
Tuesday...precipitation type and timing/intensity Tuesday into
Tuesday night...cold temps Wednesday and Wednesday night and
beyond...potential return of snow late Thursday...

There are still some signals that the pressure gradient could be
rather tight on the north side of the system Tuesday...though not
all guidance likes this idea (note that guidance still seems to be
stubbornly staying in their own corners attm, for the most part).
Would not be entirely surprised if there was some potential for
sustained winds to run around 10-20kts or greater, particularly
north of M-72 and across the UP where snow is expected...such that
blowing and drifting could be a concern to some degree. To some
extent, it may be just as well that the stronger wind potential is
further north, given the significant icing potential across the
southern half of the CWA...but will have to monitor this, as some
lesser icing potential extends north of the M-72 corridor. There is
some potential for a period of strong winds immediately behind the
system as the cold front sweeps through southwest Lower Tuesday
night, particularly closer to southwest Lower...though this remains
somewhat uncertain as well. With regard to gusts...very strong
inversion aloft will likely keep the bulk of the stronger winds
aloft well aloft...though strongest winds aloft with this system
will likely be to our south in the warm sector, and there may be
very little potential to mix any of this down until the cold front
comes through later Tuesday evening/Tuesday night as the inversion
aloft weakens.

Guidance continues to stubbornly struggle with the northward extent
of the warm air Tuesday ahead of the system...with minimal shifts
noted in the track between the 6z and 12z runs today...though
potentially a slight northward/warmer shift, even in guidance that
has been colder/further southeast. This is perhaps a little
disconcerting to some extent...mainly because it indicates potential
for a greater northward extent of the impactful mixy precip/freezing
rain expected across northern Lower with this system. There is still
a great deal of uncertainty in the position of the warm front across
central Lower Tuesday as well...noting that some ensemble guidance
shows a decent spread in 2-meter (effectively, for our purposes)
surface temps for Tuesday across areas largely south of M-68/M-32
and especially M-72, which suggests some continued uncertainty in
where exactly the transition between sleet and freezing rain will
ultimately lie...though we still expect best freezing rain chances
along and south of M-72, where the warm layer aloft should be a bit
deeper, and the cold layer near the surface, shallower, indicating a
greater potential for precipitation to remain liquid by the time it
reaches the ground. It wouldn't even be out of the question for some
areas toward Saginaw Bay in particular to get above freezing at the
surface at times, which could help switch things over to rain for a
period of time (or go back and forth between freezing rain and
rain)...again, depending on how far north the warm front is able to
get. Things are much more straightforward regarding p-type across
eastern Upper, where the column will remain cold enough for all snow
through the event. That being said...it wouldn't be entirely out of
the question for some sleet to mix in near the Straits if the warm
nose gets far enough north. Temperatures falling well below freezing
through the night Tuesday night into Wednesday morning across the
CWA indicates we will not melt any of what falls (and any liquid
will freeze on surfaces/roads). Signals point toward temps remaining
below freezing for the rest of the week attm...so we may be stuck
with the ice for a while, save for any potential sunshine that could
help melt things at times.

As we go into Tuesday morning...will be looking for current jet max
aloft to depart...with a 140+kt max to our south lifting
northeastward through the flow ahead of the surface
system...allowing better forcing aloft with potential jet coupling
to depart. That being said...forcing should return rather quickly
through the day...as this jet max lifts northeastward through the
area...and we end up in the right entrance region of the jet,
favored for upper level divergence...with additional forcing related
to the negatively tilted niblet of energy impinging on the Great
Lakes. Could see a bit more in the way of jet coupling Tuesday
afternoon as well...noting a second jet max just upstream in the
flow. Frontogenetic forcing will remain possible across eastern
Upper, suggesting enhancement of snowfall across that area.
Additionally...am seeing some signals for frontogenetic forcing
potential across northern Lower, which could be problematic with
regard to the freezing rain/sleet across this area Tuesday morning
into the afternoon, as it could locally enhance precipitation rates
across these areas and would have potential to locally increase
accumulations. Something to keep an eye on.

Quite anomalous moisture spreads north into the Great Lakes through
the night tonight into Tuesday...pwat values potentially exceeding
0.7 inches across northern Lower would be on the high end of climo
for this time of year; values will be much higher across southern
Lower in the warm sector of the system. Mid-level moisture Tuesday
morning has a bit of a splotchy look in plan views...suggesting
perhaps a little more of a convective feel at times early in the day
Tuesday...? A little uncertain on this, to be honest, and if it
occurred, it would have to be elevated, given the strong inversion
at the surface...though lapse rates between 500-700mb should be
relatively steep thanks also to that warm nose in the mid-levels. Do
see better signals for lower-level instability across southern
Michigan in the warm sector, and as mentioned yesterday, may have to
see if convection to our south (even further south than southern
lower) robs us of better moisture. Mid-level moisture deepens as we
go into midday Tuesday ahead of the surface cyclone and its
associated cold front to our southwest, and will look for another
uptick in precipitation/intensity perhaps starting as early as
midday Tuesday or early Tuesday afternoon into Tuesday evening
across the area, with wrap-around moisture lingering along the 700mb
trough aloft across the UP Tuesday night into Wednesday morning.
That being said...even if there is a "lull"...will expect that it
will not completely quit precipitating...intensity should just
become lighter at times, noting forcing and at least boundary layer
moisture seem to generally remain collocated through the event. As
winds become more northwesterly behind the front and temperatures
aloft fall again...will look for some lake effect to develop later
in the evening into the overnight as overlake instability
increases...though signals attm for lake convection are not terribly
strong, noting a lot of dry air in the mid-levels and near the
surface as subsidence aloft and cold, dry surface high pressure make
their way into the region through the night into Wednesday.

Beyond Tuesday night...will look for a bit of light lake effect
Wednesday, with some potential for mesoscale-driven lake effect
Wednesday night over the lakes. It will be chilly, however...with
cold, dry, northerly/northeasterly flow into the area as high
pressure attempts to settle into the Midwest (with some lake
aggregate effects on the pressure pattern). Wind chills late Tuesday
night into early Wednesday across eastern Upper could be in the
minus teens F...making for a bitter cleanup morning Wednesday
morning. Highs will likely be in the teens at best across our CWA
Wednesday, with lows Wednesday night potentially dropping below zero
as that drier airmass advects in...and will look for the coldest
readings across eastern Upper and parts of northern Lower where
skies become clear Wednesday night. Below normal temps look to
continue through the end of the week (and perhaps beyond)...which
will be problematic not only for clearing/melting of ice (as regular
old sodium chloride (i.e., table salt) is not as effective at
melting ice when temps are in the teens and colder)...but also for
any who lose power through this first event and do not have
alternate heating/power sources.

As we go into Thursday...will look for moisture to spread northward
through the day north of the baroclinic zone again...as the BCZ
buckles across the center of the CONUS in response to the upper-
level trough axis ejecting out of the Rockies. Surface low with this
system looks to remain across the Ohio Valley attm, given that the
BCZ will have shifted southward behind the current system...and
perhaps southern Ohio Valley...which would indicate all snow for
northern Michigan...if it even impacts us at all. Will have to
monitor this going forward...as we'll be looking at additional
snowfall late Thursday into Thursday night. Note that a further
south and east shift to the storm track for the late week system
would likely shift the highest snowfall amounts toward
central/southeast Lower and Saginaw Bay...potentially adding some
snow on top of the ice expected to fall across those areas tonight
into Tuesday. Another something to watch in the coming days.

&&

.SHORT TERM...(Tuesday through Thursday)
Issued at 315 PM EST Mon Feb 21 2022

High Impact Weather Potential: Continuation of tonight's
accumulating snow/sleet/freezing rain event...

Pattern Synopsis/Forecast:

Last 24-48 hours has seen ridging cross the Great Lakes behind a
departing shortwave. A niblet of energy crossed through northern
Michigan late yesterday...associated with a surface system that
tracked by to our northwest, which dragged a surface cold front
southward through the region. This surface front has stalled across
the MI/IN border this morning...with a tight baroclinic zone aloft
over the state (850mb temps on 12z/21 RAOBs range from +0C at DTX, -
5C at APX, and -19C at INL)...reinforced by cold advection
associated with am expansive 1040mb surface high centered in the
Canadian Prairie provinces, oozing eastward across Ontario to our
north...and warm, moist return flow off the Gulf, thanks to a
~1030mb surface high over the Carolinas. Above this...120+kt upper
level jet max resides more or less over the BCZ...with axis
stretching from the Arrowhead of Minnesota eastward toward Maine;
similarly strong subtropical jet resides across the southeastern
US...but do note some additional jet max energy rounding the base of
the troughing across the western US this morning...with a 140+kt jet
N-S oriented jet max just upstream, along the edge of ridging in the
Gulf of Alaska. Positively tilted long-wave trough axis aloft
stretches back into the western US, taking on a steeper tilt out
over the Rockies as northern stream energy dives southward along the
West Coast and a closed low off the coast of southern California
becomes absorbed into the flow...with additional northern stream
energy (extending from a sub-490dm 500mb closed low over Hudson Bay)
pivoting southward through the Canadian Prairies behind that cold
high pressure. Steeper tilt to troughing across the western US
results in an inflection point over the lee of the Rockies...where
general area of surface low pressure is beginning to develop across
eastern Colorado/western Kansas and Nebraska. Expansive area of
moisture aloft stretches across the Northern Plains and Upper
Midwest along the northern edge of the BCZ as warm, moist air rides
up over the developing frontal zone...with a little bit of
convection developing across the Gulf coast states this morning.

Going forward...will look for a wave to ride northeastward along the
baroclinic zone, crossing Michigan Tuesday into Tuesday night.
Baroclinic zone will remain SW-NE oriented...and shift slightly
further south...as positively tilted longwave troughing holds firm
across the CONUS Wednesday..However...will look for the sharp trough
axis across the western US to begin to eject eastward going into
Thursday...as another niblet of energy dives over the ridge into the
western US Thursday into Thursday night. Ejecting trough axis
crossing the center of the country should drive another round of
cyclogenesis...which has potential to impact parts of the Great
Lakes late in the period into the start of the long term.

Primary Forecast Concerns: Potential for breezier conditions
Tuesday...precipitation type and timing/intensity Tuesday into
Tuesday night...cold temps Wednesday and Wednesday night and
beyond...potential return of snow late Thursday...

There are still some signals that the pressure gradient could be
rather tight on the north side of the system Tuesday...though not
all guidance likes this idea (note that guidance still seems to be
stubbornly staying in their own corners attm, for the most part).
Would not be entirely surprised if there was some potential for
sustained winds to run around 10-20kts or greater, particularly
north of M-72 and across the UP where snow is expected...such that
blowing and drifting could be a concern to some degree. To some
extent, it may be just as well that the stronger wind potential is
further north, given the significant icing potential across the
southern half of the CWA...but will have to monitor this, as some
lesser icing potential extends north of the M-72 corridor. There is
some potential for a period of strong winds immediately behind the
system as the cold front sweeps through southwest Lower Tuesday
night, particularly closer to southwest Lower...though this remains
somewhat uncertain as well. With regard to gusts...very strong
inversion aloft will likely keep the bulk of the stronger winds
aloft well aloft...though strongest winds aloft with this system
will likely be to our south in the warm sector, and there may be
very little potential to mix any of this down until the cold front
comes through later Tuesday evening/Tuesday night as the inversion
aloft weakens.

Guidance continues to stubbornly struggle with the northward extent
of the warm air Tuesday ahead of the system...with minimal shifts
noted in the track between the 6z and 12z runs today...though
potentially a slight northward/warmer shift, even in guidance that
has been colder/further southeast. This is perhaps a little
disconcerting to some extent...mainly because it indicates potential
for a greater northward extent of the impactful mixy precip/freezing
rain expected across northern Lower with this system. There is still
a great deal of uncertainty in the position of the warm front across
central Lower Tuesday as well...noting that some ensemble guidance
shows a decent spread in 2-meter (effectively, for our purposes)
surface temps for Tuesday across areas largely south of M-68/M-32
and especially M-72, which suggests some continued uncertainty in
where exactly the transition between sleet and freezing rain will
ultimately lie...though we still expect best freezing rain chances
along and south of M-72, where the warm layer aloft should be a bit
deeper, and the cold layer near the surface, shallower, indicating a
greater potential for precipitation to remain liquid by the time it
reaches the ground. It wouldn't even be out of the question for some
areas toward Saginaw Bay in particular to get above freezing at the
surface at times, which could help switch things over to rain for a
period of time (or go back and forth between freezing rain and
rain)...again, depending on how far north the warm front is able to
get. Things are much more straightforward regarding p-type across
eastern Upper, where the column will remain cold enough for all snow
through the event. That being said...it wouldn't be entirely out of
the question for some sleet to mix in near the Straits if the warm
nose gets far enough north. Temperatures falling well below freezing
through the night Tuesday night into Wednesday morning across the
CWA indicates we will not melt any of what falls (and any liquid
will freeze on surfaces/roads). Signals point toward temps remaining
below freezing for the rest of the week attm...so we may be stuck
with the ice for a while, save for any potential sunshine that could
help melt things at times.

As we go into Tuesday morning...will be looking for current jet max
aloft to depart...with a 140+kt max to our south lifting
northeastward through the flow ahead of the surface
system...allowing better forcing aloft with potential jet coupling
to depart. That being said...forcing should return rather quickly
through the day...as this jet max lifts northeastward through the
area...and we end up in the right entrance region of the jet,
favored for upper level divergence...with additional forcing related
to the negatively tilted niblet of energy impinging on the Great
Lakes. Could see a bit more in the way of jet coupling Tuesday
afternoon as well...noting a second jet max just upstream in the
flow. Frontogenetic forcing will remain possible across eastern
Upper, suggesting enhancement of snowfall across that area.
Additionally...am seeing some signals for frontogenetic forcing
potential across northern Lower, which could be problematic with
regard to the freezing rain/sleet across this area Tuesday morning
into the afternoon, as it could locally enhance precipitation rates
across these areas and would have potential to locally increase
accumulations. Something to keep an eye on.

Quite anomalous moisture spreads north into the Great Lakes through
the night tonight into Tuesday...pwat values potentially exceeding
0.7 inches across northern Lower would be on the high end of climo
for this time of year; values will be much higher across southern
Lower in the warm sector of the system. Mid-level moisture Tuesday
morning has a bit of a splotchy look in plan views...suggesting
perhaps a little more of a convective feel at times early in the day
Tuesday...? A little uncertain on this, to be honest, and if it
occurred, it would have to be elevated, given the strong inversion
at the surface...though lapse rates between 500-700mb should be
relatively steep thanks also to that warm nose in the mid-levels. Do
see better signals for lower-level instability across southern
Michigan in the warm sector, and as mentioned yesterday, may have to
see if convection to our south (even further south than southern
lower) robs us of better moisture. Mid-level moisture deepens as we
go into midday Tuesday ahead of the surface cyclone and its
associated cold front to our southwest, and will look for another
uptick in precipitation/intensity perhaps starting as early as
midday Tuesday or early Tuesday afternoon into Tuesday evening
across the area, with wrap-around moisture lingering along the 700mb
trough aloft across the UP Tuesday night into Wednesday morning.
That being said...even if there is a "lull"...will expect that it
will not completely quit precipitating...intensity should just
become lighter at times, noting forcing and at least boundary layer
moisture seem to generally remain collocated through the event. As
winds become more northwesterly behind the front and temperatures
aloft fall again...will look for some lake effect to develop later
in the evening into the overnight as overlake instability
increases...though signals attm for lake convection are not terribly
strong, noting a lot of dry air in the mid-levels and near the
surface as subsidence aloft and cold, dry surface high pressure make
their way into the region through the night into Wednesday.

Beyond Tuesday night...will look for a bit of light lake effect
Wednesday, with some potential for mesoscale-driven lake effect
Wednesday night over the lakes. It will be chilly, however...with
cold, dry, northerly/northeasterly flow into the area as high
pressure attempts to settle into the Midwest (with some lake
aggregate effects on the pressure pattern). Wind chills late Tuesday
night into early Wednesday across eastern Upper could be in the
minus teens F...making for a bitter cleanup morning Wednesday
morning. Highs will likely be in the teens at best across our CWA
Wednesday, with lows Wednesday night potentially dropping below zero
as that drier airmass advects in...and will look for the coldest
readings across eastern Upper and parts of northern Lower where
skies become clear Wednesday night. Below normal temps look to
continue through the end of the week (and perhaps beyond)...which
will be problematic not only for clearing/melting of ice (as regular
old sodium chloride (i.e., table salt) is not as effective at
melting ice when temps are in the teens and colder)...but also for
any who lose power through this first event and do not have
alternate heating/power sources.

As we go into Thursday...will look for moisture to spread northward
through the day north of the baroclinic zone again...as the BCZ
buckles across the center of the CONUS in response to the upper-
level trough axis ejecting out of the Rockies. Surface low with this
system looks to remain across the Ohio Valley attm, given that the
BCZ will have shifted southward behind the current system...and
perhaps southern Ohio Valley...which would indicate all snow for
northern Michigan...if it even impacts us at all. Will have to
monitor this going forward...as we'll be looking at additional
snowfall late Thursday into Thursday night. Note that a further
south and east shift to the storm track for the late week system
would likely shift the highest snowfall amounts toward
central/southeast Lower and Saginaw Bay...potentially adding some
snow on top of the ice expected to fall across those areas tonight
into Tuesday. Another something to watch in the coming days.

.SHORT TERM...(Tuesday through Thursday)
Issued at 315 PM EST Mon Feb 21 2022

High Impact Weather Potential: Continuation of tonight's
accumulating snow/sleet/freezing rain event...

Pattern Synopsis/Forecast:

Last 24-48 hours has seen ridging cross the Great Lakes behind a
departing shortwave. A niblet of energy crossed through northern
Michigan late yesterday...associated with a surface system that
tracked by to our northwest, which dragged a surface cold front
southward through the region. This surface front has stalled across
the MI/IN border this morning...with a tight baroclinic zone aloft
over the state (850mb temps on 12z/21 RAOBs range from +0C at DTX, -
5C at APX, and -19C at INL)...reinforced by cold advection
associated with am expansive 1040mb surface high centered in the
Canadian Prairie provinces, oozing eastward across Ontario to our
north...and warm, moist return flow off the Gulf, thanks to a
~1030mb surface high over the Carolinas. Above this...120+kt upper
level jet max resides more or less over the BCZ...with axis
stretching from the Arrowhead of Minnesota eastward toward Maine;
similarly strong subtropical jet resides across the southeastern
US...but do note some additional jet max energy rounding the base of
the troughing across the western US this morning...with a 140+kt jet
N-S oriented jet max just upstream, along the edge of ridging in the
Gulf of Alaska. Positively tilted long-wave trough axis aloft
stretches back into the western US, taking on a steeper tilt out
over the Rockies as northern stream energy dives southward along the
West Coast and a closed low off the coast of southern California
becomes absorbed into the flow...with additional northern stream
energy (extending from a sub-490dm 500mb closed low over Hudson Bay)
pivoting southward through the Canadian Prairies behind that cold
high pressure. Steeper tilt to troughing across the western US
results in an inflection point over the lee of the Rockies...where
general area of surface low pressure is beginning to develop across
eastern Colorado/western Kansas and Nebraska. Expansive area of
moisture aloft stretches across the Northern Plains and Upper
Midwest along the northern edge of the BCZ as warm, moist air rides
up over the developing frontal zone...with a little bit of
convection developing across the Gulf coast states this morning.

Going forward...will look for a wave to ride northeastward along the
baroclinic zone, crossing Michigan Tuesday into Tuesday night.
Baroclinic zone will remain SW-NE oriented...and shift slightly
further south...as positively tilted longwave troughing holds firm
across the CONUS Wednesday..However...will look for the sharp trough
axis across the western US to begin to eject eastward going into
Thursday...as another niblet of energy dives over the ridge into the
western US Thursday into Thursday night. Ejecting trough axis
crossing the center of the country should drive another round of
cyclogenesis...which has potential to impact parts of the Great
Lakes late in the period into the start of the long term.

Primary Forecast Concerns: Potential for breezier conditions
Tuesday...precipitation type and timing/intensity Tuesday into
Tuesday night...cold temps Wednesday and Wednesday night and
beyond...potential return of snow late Thursday...

There are still some signals that the pressure gradient could be
rather tight on the north side of the system Tuesday...though not
all guidance likes this idea (note that guidance still seems to be
stubbornly staying in their own corners attm, for the most part).
Would not be entirely surprised if there was some potential for
sustained winds to run around 10-20kts or greater, particularly
north of M-72 and across the UP where snow is expected...such that
blowing and drifting could be a concern to some degree. To some
extent, it may be just as well that the stronger wind potential is
further north, given the significant icing potential across the
southern half of the CWA...but will have to monitor this, as some
lesser icing potential extends north of the M-72 corridor. There is
some potential for a period of strong winds immediately behind the
system as the cold front sweeps through southwest Lower Tuesday
night, particularly closer to southwest Lower...though this remains
somewhat uncertain as well. With regard to gusts...very strong
inversion aloft will likely keep the bulk of the stronger winds
aloft well aloft...though strongest winds aloft with this system
will likely be to our south in the warm sector, and there may be
very little potential to mix any of this down until the cold front
comes through later Tuesday evening/Tuesday night as the inversion
aloft weakens.

Guidance continues to stubbornly struggle with the northward extent
of the warm air Tuesday ahead of the system...with minimal shifts
noted in the track between the 6z and 12z runs today...though
potentially a slight northward/warmer shift, even in guidance that
has been colder/further southeast. This is perhaps a little
disconcerting to some extent...mainly because it indicates potential
for a greater northward extent of the impactful mixy precip/freezing
rain expected across northern Lower with this system. There is still
a great deal of uncertainty in the position of the warm front across
central Lower Tuesday as well...noting that some ensemble guidance
shows a decent spread in 2-meter (effectively, for our purposes)
surface temps for Tuesday across areas largely south of M-68/M-32
and especially M-72, which suggests some continued uncertainty in
where exactly the transition between sleet and freezing rain will
ultimately lie...though we still expect best freezing rain chances
along and south of M-72, where the warm layer aloft should be a bit
deeper, and the cold layer near the surface, shallower, indicating a
greater potential for precipitation to remain liquid by the time it
reaches the ground. It wouldn't even be out of the question for some
areas toward Saginaw Bay in particular to get above freezing at the
surface at times, which could help switch things over to rain for a
period of time (or go back and forth between freezing rain and
rain)...again, depending on how far north the warm front is able to
get. Things are much more straightforward regarding p-type across
eastern Upper, where the column will remain cold enough for all snow
through the event. That being said...it wouldn't be entirely out of
the question for some sleet to mix in near the Straits if the warm
nose gets far enough north. Temperatures falling well below freezing
through the night Tuesday night into Wednesday morning across the
CWA indicates we will not melt any of what falls (and any liquid
will freeze on surfaces/roads). Signals point toward temps remaining
below freezing for the rest of the week attm...so we may be stuck
with the ice for a while, save for any potential sunshine that could
help melt things at times.

As we go into Tuesday morning...will be looking for current jet max
aloft to depart...with a 140+kt max to our south lifting
northeastward through the flow ahead of the surface
system...allowing better forcing aloft with potential jet coupling
to depart. That being said...forcing should return rather quickly
through the day...as this jet max lifts northeastward through the
area...and we end up in the right entrance region of the jet,
favored for upper level divergence...with additional forcing related
to the negatively tilted niblet of energy impinging on the Great
Lakes. Could see a bit more in the way of jet coupling Tuesday
afternoon as well...noting a second jet max just upstream in the
flow. Frontogenetic forcing will remain possible across eastern
Upper, suggesting enhancement of snowfall across that area.
Additionally...am seeing some signals for frontogenetic forcing
potential across northern Lower, which could be problematic with
regard to the freezing rain/sleet across this area Tuesday morning
into the afternoon, as it could locally enhance precipitation rates
across these areas and would have potential to locally increase
accumulations. Something to keep an eye on.

Quite anomalous moisture spreads north into the Great Lakes through
the night tonight into Tuesday...pwat values potentially exceeding
0.7 inches across northern Lower would be on the high end of climo
for this time of year; values will be much higher across southern
Lower in the warm sector of the system. Mid-level moisture Tuesday
morning has a bit of a splotchy look in plan views...suggesting
perhaps a little more of a convective feel at times early in the day
Tuesday...? A little uncertain on this, to be honest, and if it
occurred, it would have to be elevated, given the strong inversion
at the surface...though lapse rates between 500-700mb should be
relatively steep thanks also to that warm nose in the mid-levels. Do
see better signals for lower-level instability across southern
Michigan in the warm sector, and as mentioned yesterday, may have to
see if convection to our south (even further south than southern
lower) robs us of better moisture. Mid-level moisture deepens as we
go into midday Tuesday ahead of the surface cyclone and its
associated cold front to our southwest, and will look for another
uptick in precipitation/intensity perhaps starting as early as
midday Tuesday or early Tuesday afternoon into Tuesday evening
across the area, with wrap-around moisture lingering along the 700mb
trough aloft across the UP Tuesday night into Wednesday morning.
That being said...even if there is a "lull"...will expect that it
will not completely quit precipitating...intensity should just
become lighter at times, noting forcing and at least boundary layer
moisture seem to generally remain collocated through the event. As
winds become more northwesterly behind the front and temperatures
aloft fall again...will look for some lake effect to develop later
in the evening into the overnight as overlake instability
increases...though signals attm for lake convection are not terribly
strong, noting a lot of dry air in the mid-levels and near the
surface as subsidence aloft and cold, dry surface high pressure make
their way into the region through the night into Wednesday.

Beyond Tuesday night...will look for a bit of light lake effect
Wednesday, with some potential for mesoscale-driven lake effect
Wednesday night over the lakes. It will be chilly, however...with
cold, dry, northerly/northeasterly flow into the area as high
pressure attempts to settle into the Midwest (with some lake
aggregate effects on the pressure pattern). Wind chills late Tuesday
night into early Wednesday across eastern Upper could be in the
minus teens F...making for a bitter cleanup morning Wednesday
morning. Highs will likely be in the teens at best across our CWA
Wednesday, with lows Wednesday night potentially dropping below zero
as that drier airmass advects in...and will look for the coldest
readings across eastern Upper and parts of northern Lower where
skies become clear Wednesday night. Below normal temps look to
continue through the end of the week (and perhaps beyond)...which
will be problematic not only for clearing/melting of ice (as regular
old sodium chloride (i.e., table salt) is not as effective at
melting ice when temps are in the teens and colder)...but also for
any who lose power through this first event and do not have
alternate heating/power sources.

As we go into Thursday...will look for moisture to spread northward
through the day north of the baroclinic zone again...as the BCZ
buckles across the center of the CONUS in response to the upper-
level trough axis ejecting out of the Rockies. Surface low with this
system looks to remain across the Ohio Valley attm, given that the
BCZ will have shifted southward behind the current system...and
perhaps southern Ohio Valley...which would indicate all snow for
northern Michigan...if it even impacts us at all. Will have to
monitor this going forward...as we'll be looking at additional
snowfall late Thursday into Thursday night. Note that a further
south and east shift to the storm track for the late week system
would likely shift the highest snowfall amounts toward
central/southeast Lower and Saginaw Bay...potentially adding some
snow on top of the ice expected to fall across those areas tonight
into Tuesday. Another something to watch in the coming days.

.LONG TERM...(Thursday night through Monday)
Issued at 315 PM EST Mon Feb 21 2022

High Impact Weather Potential: Potential snowfall Thursday night
into early Friday?...active weather may continue into early next
week...

Pattern Synopsis/Forecast:

As mentioned at the end of the short term discussion...sharp
shortwave trough will be ridging the baroclinic zone northeastward
into the Great Lakes/Ohio Valley Thursday night into
Friday...driving another round of cyclogenesis ahead of it.
Attm...current guidance suggests this may be on its way out by
Friday morning...with some additional niblets of northern stream
energy potentially swinging through the region behind it. Additional
northern stream energy looks to drop in for the weekend...which
suggests we should remain cold through the end of February...as
lingering troughing across the western US struggles to hold on, but
ultimately appears to become absorbed by the flow at some point
(details yet unclear). We may be looking at another pattern
change...back to the ridging west/troughing east setup that brought
us cold and clippery weather for what seems like the bulk of the
last several weeks...an idea which is (and has been) supported by
CPC guidance through the end of February and into the start of
March.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 602 PM EST Mon Feb 21 2022

...ICING POTENTIAL AND MVFR/IFR CIGS...

A long duration winter storm is expected to overspread northern
Michigan this evening through Tuesday night. Clouds will
lower/thicken with prevailing MVFR/IFR conditions expected
tonight through the end of the TAF period. Ice accumulations are
expected at TVC, MBL, and to a somewhat lesser extent APN. Better
chances for less ice/more snow at PLN. winds will be gusty from
the east/northeast throughout the TAF period.

&&

.MARINE...
Issued at 315 PM EST Mon Feb 21 2022

East-northeast winds this afternoon will continue to reach Small
Craft Advisory criteria area-wide through Tuesday...potentially with
a few low-end gale gusts as times, especially along the Lake Huron
shoreline given onshore flow. Small Craft conditions likely to
continue on the Lake Huron side through Tuesday afternoon, but will
probably lingering on the Lake Michigan side into Tuesday night
south of Grand Traverse Light.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...ICE STORM WARNING until midnight EST Tuesday night for
     MIZ025>036.
     WINTER WEATHER ADVISORY until midnight EST Tuesday night for
     MIZ016>018-020>024-041-042-086>088-095>099.
LH...SMALL CRAFT ADVISORY until 5 PM EST Tuesday for LHZ345>349.
LM...SMALL CRAFT ADVISORY until 5 PM EST Tuesday for LMZ323-341-342.
     SMALL CRAFT ADVISORY until 7 AM EST Wednesday for LMZ344>346.
LS...NONE.
&&

UPDATE...JK
NEAR TERM...MJG
SHORT TERM...FEF
LONG TERM...FEF
AVIATION...JK
MARINE...MJG

Hazardous Weather Outlook
National Weather Service Gaylord MI
947 PM EST Mon Feb 21 2022

MIZ016>018-020>036-041-042-086>088-095>099-230300-
Emmet-Cheboygan-Presque Isle-Leelanau-Antrim-Otsego-Montmorency-
Alpena-Benzie-Grand Traverse-Kalkaska-Crawford-Oscoda-Alcona-
Manistee-Wexford-Missaukee-Roscommon-Ogemaw-Iosco-Gladwin-Arenac-
Western Chippewa-Central Chippewa-Southeast Chippewa-
Western Mackinac-Eastern Mackinac-
Mackinac Island/Bois Blanc Island-
Beaver Island and surrounding islands-Charlevoix-
947 PM EST Mon Feb 21 2022

This hazardous weather outlook is for Eastern Upper Michigan and
Northern Lower Michigan.

.DAY ONE...Tonight.

A mix of precipitation types will overspread northern Michigan
overnight. Snow is expected across eastern Upper Michigan...with
snow/sleet/freezing rain expected across northern Lower Michigan.
The greatest ice accumulations are expected along and south of
M-72. Please see the ongoing Ice Storm Warning and Winter Weather
Advisories for additional details.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Wintry precipitation will continue through Tuesday night...with
primarily snow expected across eastern Upper Michigan and a
continued threat for snow/sleet/freezing rain across northern Lower
Michigan. Significant ice accumulations are expected along and south
of M-72 with tree damage and power outages possible. Please see the
ongoing Ice Storm Warning and Winter Weather Advisories for
additional details.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report any significant weather and
snow or ice amounts to the National Weather Service. Reports may
be made one of three ways:

Online:   weather.gov/gaylord
Facebook: facebook.com/nwsgaylord
Twitter: twitter.com/nwsgaylord

For more information visit http://weather.gov/gaylord.

LHZ345>349-LMZ323-341-342-344>346-LSZ321-322-230300-
Straits of Mackinac within 5 nm of Mackinac Bridge including
Mackinac Island-St Ignace to False Detour Channel-
5NM East of Mackinac Bridge to Presque Isle Light MI including
Bois Blanc Island-
Presque Isle Light to Sturgeon Pt MI Including Thunder Bay
National Marine Sanctuary-Sturgeon Pt to Alabaster MI-
Grand Traverse Bay south of a line Grand Traverse Light to
Norwood MI-Seul Choix Point to 5NM West of Mackinac Bridge-
Norwood MI to 5NM West of Mackinac Bridge including Little
Traverse Bay-Sleeping Bear Point to Grand Traverse Light MI-
Point Betsie to Sleeping Bear Point MI-
Manistee to Point Betsie MI-
Whitefish Bay (U.S. Portion)/Whitefish Point to Point Iroquois MI-
St. Marys River Point Iroquois to E. Potagannissing Bay-
947 PM EST Mon Feb 21 2022

This hazardous weather outlook is for the northern Michigan
nearshore waters of Lake Huron, Lake Michigan and Lake Superior.

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

For more information visit http://weather.gov/gaylord.