Area Forecast Discussion
Issued by NWS Gaylord, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KAPX 012016

Area Forecast Discussion
National Weather Service Gaylord MI
316 PM EST Wed Mar 1 2017

.NEAR TERM...(Tonight and Thursday)
Issued at 254 PM EST Wed Mar 1 2017

...Widespread snow ends tonight...

High Impact Weather Potential: Lingering moderate to heavy snow into
this evening.

Pattern Synopsis/Forecast: Compact shortwave set to cross the area
later today into this evening. Strong dynamics tied nicely to
low/mid level fgen response and remnant deeper moisture plume
continues to produce quite the snow event, particularly across the
Tip of the Mitt counties into parts of eastern upper Michigan.
Widespread reports of greater than 5 inches of snow in this region,
and that was a few hours ago. No doubt some areas have experienced
several inches more, with several more hours of accumulating snow
yet to go in this region. Further south, somewhat lower changeover
and less distinct banding structures have kept snow totals in check,
although these too are beginning to increase as corridor of best mid
level support arrives. Still a rain/snow mixture down near Saginaw
Bay, with north flow cold air advection looking to change this area
over to snow shortly.

Pattern remains progressive overnight, with that shortwave trough
exiting stage right later this evening, followed by a shot of colder
air and possible light lake effect snows for Thursday.

Primary forecast concerns: Additional snow amounts into this evening
and associated headlines.

Details: Bands of snow, intense at times as fgen maximizes, will
continue to pivot east across the area this afternoon into early
evening. Already have seen snow intensity drop off for areas north
of the bridge, and this trend should continue to drop southeast as
corridor of best forcing passes this evening. Based off fgen
potential, would still expect to see several more inches of snow for
areas of northern lower Michigan, particularly north of M-72. Lesser
amounts further south where fgen banding will remain more transient.
Still have plenty of concern just how much snow will be realized for
areas down near Saginaw Bay, and per trends, they do look to fall
short of advisory snow amounts. However, given steadily falling
temperatures and bands of at times heavy snow yet to impact that
area, feel leaving inherited advisory is the best course of action.
Otherwise, all inherited headlines will remain. Snow will end rather
quickly heading through the evening from west to east, leaving
behind partly cloudy skies and rather chilly temperatures. May see a
few lake effect snow showers develop late in favored northwest flow
areas. Nothing significant for sure with no synoptic moisture
contribution and really shallow inversion heights.

Above trends continue into Thursday, although passage of subtle wave
during the late morning/early afternoon may enhance lake snows just
a bit. Still, not expecting much more than a dusting with strong
surface based inverted-v signature and sub h8 inversion levels.
Highs tomorrow will be several degrees below normal for a change,
with afternoon readings only in the 20s.


.SHORT TERM...(Thursday night through Saturday)
Issued at 254 PM EST Wed Mar 1 2017

...Lake effect snow showers through Friday...

High impact weather potential: Mainly light lake effect snow showers
Thursday night through Friday.

Pattern Forecast: Broad northwesterly flow focused across the Great
Lakes is expected to continue Thursday night with an upper level
shortwave and weak surface reflection progged to be sliding through
Illinois/Indiana with a light area of snow. Cold air aloft continues
to spill in with earnest overnight into Friday morning with H8 temps
falling to nearly -20 C overhead...setting the stage for lake effect
snow showers to continue through Friday afternoon before diminishing
as surface ridging/WAA prevail for the weekend.

Primary Forecast Concerns: Primary forecast concerns lie around lake
effect snow chances and amounts as a surge of much colder air pushes
into the northern Great Lakes from southern Ontario. As was
mentioned above, H8 temps fall from roughly -15 C at 00z Friday to
-20 C by 12z Friday. Model forecast soundings suggest an increase to
deep layer moisture and synoptic support for a period of time late
Thursday afternoon and evening associated with the aforementioned
shortwave rippling through the southern Great Lakes. An uptick in
northwest flow lake induced snow shower coverage and intensity seems
likely Thursday evening as subsidence inversion heights become
nearly non-existent and negative omega pegs squarely in the DGZ for
a brief window Thursday evening. However, as the night wears on,
inversion heights begin to fall (dropping to ~6 kft) as mid level
moisture quickly strips out toward the southeast.

Similar thermodynamic regime expected for at least the first half of
Friday with mainly light lake effect snow showers ongoing across
northwest flow targeted lake belts. Subtle backing of the low level
winds to more west-northwesterly flow throughout the day should
focus steadiest snow showers toward the M-32 corridor, but again,
mainly light in nature before snow shower coverage and intensity
diminish during the late afternoon and evening as heights rise aloft
and surface ridging noses into northern Michigan. In terms of snow
accumulations, expecting the majority Thursday evening/night to be
across northwest flow zones Thursday night with up to a couple of
inches of fluffy/dry snow possible (lesser amounts elsewhere, to
none across the southeastern counties). Accumulations shift to west-
northwest flow areas during the day Friday with an additional inch
or two possible in lake belts.

All but a few lingering flurries diminish Friday evening with
temperatures beginning to moderate on Saturday as thermal ridging
arrives from the west. Highs Friday in the upper teens to low 20s,
climbing to the low-mid 30s Saturday.


.LONG TERM...(Saturday night through Wednesday)
Issued at 254 PM EST Wed Mar 1 2017

While a clipper could bring some scattered rain/snow across the area
Sunday, the main concern over the extended period remains the system
Monday/Tuesday. The details are still a bit divergent, but most
guidance is coming together with a track to our north. This should
result in rain across the area during the daytime hours, with some
areas seeing a switch to snow overnight Monday and Tuesday.
Temperatures will run well above normal into mid-week, when another
clipper looks to move in behind the early week system, bringing
another shot of cold air. This will bring temperatures back to near
normal ranges, along with some lake effect snow Wednesday.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1218 PM EST Wed Mar 1 2017

IFR to LIFR conditions today in heavy snow and blowing snow.
Improving conditions tonight into Thursday morning.

Snow, at times very heavy, will continue to spread across the taf
sites this afternoon into early this evening. Blowing snow will
also develop. Conditions will improve from west to east this
evening, with mainly VFR conditions expected later tonight into
early Thursday. Winds will also decrease, ending the blowing snow

Snow to liquid ratios, while initially rather low, will increase
through the day as colder air steadily filters into the region.


Issued at 254 PM EST Wed Mar 1 2017

Gusty north to northwest winds will slowly subside tonight
as low pressure responsible for such pushes off to the east. Sub-
advisory level northwest winds expected on Thursday.


MI...WINTER WEATHER ADVISORY until 1 AM EST Thursday for MIZ024>036-
     WINTER STORM WARNING until 1 AM EST Thursday for MIZ016>023.
     WINTER STORM WARNING until 10 PM EST this evening for MIZ008-015.
LH...SMALL CRAFT ADVISORY until 4 AM EST Thursday for LHZ345>349.
LM...SMALL CRAFT ADVISORY until 4 AM EST Thursday for LMZ323-341-342-


MARINE...MSB is the U.S. government's official web portal to all federal, state and local government web resources and services.