902
FXUS63 KGRR 280503
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
1203 AM EST Sat Feb 28 2026
.KEY MESSAGES...
- Slightly greater snow accumulations Saturday afternoon/evening
- Rain chances return Tuesday
- Wet and warmer Wednesday through Friday
&&
.DISCUSSION...
Issued at 225 PM EST Fri Feb 27 2026
- Slightly greater snow accumulations Saturday afternoon/evening
Latest deterministic model guidance indicates total snow accumulations
greater than 2 inches north of a Muskegon to Alma line and centered
in the US-10 vicinity by Sunday morning. This is a bit of an outlier
compared to post-processed ensemble guidance such as NBM version 5
and the 12Z SPC HREF, which both indicate about a 30 to 40 percent
chance of exceeding 2 inches in this area. The greatest snowfall rates
look to occur in the 8 pm to midnight timeframe Saturday night. The
Mount Pleasant to Big Rapids corridor may see the greatest accumulations
thanks to favorable placement underneath the expected FGEN band combined
with lake enhancement associated with N-NE flow off Lake Huron and
Saginaw Bay.
Lesser accumulations on the order of an inch or less are expected
farther south all the way towards the I-94 corridor according to the
aforementioned deterministic guidance. That said, the 12Z HREF does
indicate a secondary relative maximum of 1-1.5" around I-94 in the
overnight hours.
On the heels of these detailed descriptions I will hasten to add that,
as noted previously, amounts and location remain rather uncertain given
questions about moisture, microphysics, and FGEN band placement. However,
the consistent theme has been that this looks like an non-impactful
event given expected amounts and timing of snow.
- Rain chances return Tuesday
As noted before, we are looking at moderating temperatures through the
week. However, one change is that we now see a northern stream upper
PV max approaching the western Great Lakes Tuesday and crossing Tuesday
night. This ought to provide a rain/snow mix Tuesday and Tuesday night
north of a stationary front where PV forcing will be coupled with lower
tropospheric isentropic lift.
- Wet and warmer Wednesday through Friday
Model guidance continues to forecast a wet and unsettled pattern,
especially in the Thursday/Friday timeframe. ECMWF ensemble guidance
shows about a 10-20 percent chance of seeing freezing rain during this
time, which is a distinct possibility given that cold/dry advecting
east-northeast low level flow may be present. This will have to be
watched.
By the time we get to Friday, chances for mixed precipitation are reduced,
but chances for thunder and significant rainfall both increase. Predictability
remains very limited this far out, but there does appear some probability
(10-20 percent) exists for having rainfall that could produce at least
some minor flooding concerns.
&&
.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1203 AM EST Sat Feb 28 2026
VFR is likely through about 21 Z, then the chance of MVFR ceiling
and MVFR to IFR visibility with snow starts to increase. The onset
of the deteriorating conditions with snow is fairly low
confidence, as there remains a high model spread in the envelope
of possible outcomes regarding where the axis of heaviest
precipitation sets up across central to southern Lower Michigan.
Will ease into the change with some 3-hour long prob30s. The
chance of IFR vis after 00 Z is a little higher around MKG-GRR-LAN
than it is around AZO-BTL-JXN, but both do have enough of a chance
to include in the TAFs.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...TJT
AVIATION...CAS
NWS GRR Office Area Forecast Discussion
