827
FXUS63 KGRR 131804
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
204 PM EDT Fri Mar 13 2026
.KEY MESSAGES...
- Rain and Snow, Briefly Heavy Snow in Central Michigan This
Morning
- Windy Today
- Winter Storm Possible Saturday Night Through Monday
&&
.UPDATE...
Issued at 1047 AM EDT Fri Mar 13 2026
We wanted to give a brief update given all of the headlines out
for the area. The only change to headlines this morning was to
extend the time of the Winter Weather Advisory for the far NE
section of the area through this evening. All headlines remain
unchanged for now.
Initial burst of snow overnight created the impacts pretty much as
expected. Some of the better snow accumulations snuck into the far
northern portion of Kent County. We now have some warmer air in
place briefly in the warm sector, with the sfc low about ready to
move through the area over the next few hours. In addition, we
have upper level wave moving through that will not clear the
entire area until toward 06z tonight.
North of the sfc low and in the favored deformation zone of the
upper low, will be the interior portions of Central Lower and
northward. It is here that another 1 to 3 inches or so will fall
from this afternoon through this evening. Combine that with the
strong winds, and it is very much justified to extend this
advisory.
All looks good for the High Wind Warning. Gusts are hitting
criteria right now with the colder air returning behind the low.
The only area not in the Warning still looks to stay below
warning, so no need to extend there.
No changes to the Winter Storm watch at this time either. We will
look at the 12z suite in a more holistic view to see if the NW
trend continues. We will consider any changes for the watch this
afternoon.
&&
.DISCUSSION...
Issued at 412 AM EDT Fri Mar 13 2026
- Rain and Snow, Briefly Heavy Snow in Central Michigan This Morning
No changes to the existing winter weather advisory. Robust clipper
system moving through today will bring a shot of 1 inch per hour
snowfall rates to Central Michigan for the morning commute (SPC
mesoscale discussion 236 for more details). The HREF has been
signaling this to occur especially between 6 and 9 AM for areas near
and north of Ludington, White Cloud, Big Rapids/Canadian Lakes, and
Mount Pleasant. Around 6 inch totals are most favored in Lake,
Osceola, and Clare counties. Farther south toward I-96 and I-94, a
tendency for more of a snow to rain and back to snow with more minor
accumulations.
- Windy Today
No change to the high wind warning. Upstream observations in
northern Illinois suggest strong wind gusts up to 60 mph possible
this morning with onset of precipitation. May be a bit of lull in
the peak gusts later in the morning given limited mixing due to
clouds and precipitation. Also with a slight southward adjustment to
the low`s track, a midday lull may be more pronounced in the
northernmost row of counties. But additional strong wind gusts are
possible throughout the warning area during the afternoon with
modest cold air advection. End time of the high wind warning might
need to be bumped a couple hours later in the evening, closer to 10
PM.
- Winter Storm Possible Saturday Night Through Monday
Matching up with APX on a winter storm watch for Saturday night
through Monday for areas near/north of M-20. While much of APX will
be square in the threat for a significant winter storm, our southern
portion of Central Michigan has some potential (50 to 60 percent) to
catch moderate storm-level impacts but it is not quite settled. Our
area`s weather on Sunday will be especially sensitive to the exact
track of the low pressure center, and the latest ECMWF ENS envelope
has shifted slightly north, which reduces our winter storm potential
slightly. However, there remain solutions within the envelope that
do have the low passing through SE Michigan which would entail
higher impacts still possible in the watch area. WSSI-P indicates
about a 20-30 percent chance of major impacts given those solutions.
Expecting snow late Saturday night ahead of the developing low,
followed by warming (especially in southeastern locations near and
southeast of the low`s track) on Sunday. Can`t rule out a
thunderstorm on Sunday but MUCAPE is progged to be fairly weak. If
storms do occur, there is a marginal risk near and south of I-96
for severe wind gusts given the strengthening low-level wind
field. There is potential for ice accretion from freezing rain in
Central Michigan Sunday through Sunday night, and some of the
southern model solutions have been producing over a quarter- inch
of ice. Behind on the backside of the low on Monday, a change over
to lake- enhanced snow and strong winds is expected, with more of
Southwest Michigan getting in on winter impacts.
&&
.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 200 PM EDT Fri Mar 13 2026
MVFR cigs and vsbys in rain and snow will continue through the
afternoon. Plan on MVFR to IFR much of the day for most of the
area. Strong low pressure system moving through with rain and snow
showers today, gusty winds 30 up to 55 knots. While there could be
periods of LLWS the strongest winds will make it to the surface
and any winds aloft will be within 30 degrees. There will be
another swath of precip this evening between 22Z and 02Z. After
that conditions will slowly improve. Winds will drop between 02Z
and 05Z, and then below 10kts between 05Z and 10Z.
&&
.MARINE...
Issued at 441 AM EDT Fri Mar 13 2026
Storm force gusts from the southwest are occurring now and remain
possible through the day from the west, especially south of
Pentwater to St Joseph. A gale warning is also in effect to the
north of Pentwater. Winds subside below gale by 11 PM, then a
small craft advisory will be needed through mid Saturday morning.
Hazardous conditions for small craft develop again late Saturday
night. Gales are likely and storm force winds are possible Sunday
night and Monday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...High Wind Warning until 8 PM EDT this evening for MIZ037-043>046-
050>052-056>059-064>067-071>074.
Winter Storm Watch from late Saturday night through Monday
evening for MIZ037>040-043>045.
Winter Weather Advisory until 2 AM EDT Saturday for MIZ038>040-
044>046.
MARINE...Storm Warning until 11 PM EDT this evening for LMZ844>848.
Gale Warning until 11 PM EDT this evening for LMZ849.
&&
$$
UPDATE...NJJ
DISCUSSION...CAS
AVIATION...Ceru
MARINE...CAS
NWS GRR Office Area Forecast Discussion
