294
FXUS63 KGRR 281706
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
1206 PM EST Fri Feb 28 2025

.KEY MESSAGES...

- Windy Today into Tonight

- Slick Roads Possible Tonight into Saturday Morning

- Light Rain Tue, Then Heavier Rain or Snow with Wind on Wed

&&

.UPDATE...
Issued at 1127 AM EST Fri Feb 28 2025

Wind gusts have been under-performing so far as compared to prior
guidance at 16Z such as the 06Z HRRR. However we have seen some
gusts over 35 mph at the lakeshore. Probably what`s holding it
back is the thicker cloud cover still overhead. The clouds are
expected to thin/decrease to some extent and peeks of sun should
promote deeper mixing with some briefly higher gusts being
realized this afternoon. The radar VWP currently shows 40 kts at
2K ft and 55 kts at 3K ft, so those stronger winds are up there to
be tapped. No changes to the wind advisory at this time.

&&

.DISCUSSION...
Issued at 346 AM EST Fri Feb 28 2025

- Windy Today into Tonight

A southwesterly jet 45-60 knots at 925-850 mb will translate
eastward over the southern half of Lower Michigan later this
morning to mid afternoon. Despite mid/high altitude cloud cover,
most models indicate a deepening mixed layer off the surface as
strong warm air advection at the surface occurs while the 900-850
layer cools. Gusts to 45 mph are possible through early/mid
afternoon, followed by a slight weakening in wind speeds before an
uptick in west-northwest winds behind a strong cold front this
evening into early tonight. The lakeshore counties better suited
to see both phases of 45 mph gusts today and tonight, while
farther inland it will still be quite breezy but perhaps not
enough to continue the advisory longer.

- Slick Roads Possible Tonight into Saturday Morning

Light snow amounts may fall in Central Michigan this morning from
the warm side of this Clipper system, as precipitation from
midlevel clouds falls into drier air, but not very confident in
this. The main concern for impacts to road surfaces will be
tonight into Saturday morning in West Michigan. Temperatures will
drop well into the 20s, and in some spots the teens, by Saturday
morning, and lake-enhanced snow showers produce a dusting to
locally 2 inch accumulation.

- Light Rain Tue, Then Heavier Rain or Snow with Wind on Wed

High confidence from strong ensemble system support of a large
midlatitude cyclone tracking from the Central Plains to the
Southern Great Lakes Tue-Wed. Light rain showers are possible on
Tuesday ahead of this low, but the main precipitation should
arrive Tue night into part of the day Wed. Interquartile range of
QPF from the ECE, GEFS, and CMC is 0.5 to 1 inch. Snow is possible
in the deformation zone on the northwest side of the low`s track,
and there is a non-majority constituency of members that produce
advisory-level snow in our CWA (better chance in areas northwest).
It follows that the high temperature forecast for Wed is quite
uncertain depending on where the low tracks. It also looks quite
windy on the back side of the low, with northwest gusts over 40
mph possible.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1206 PM EST Fri Feb 28 2025

Winds have increased to 17-22 knots with gusts to 40 knots, ending
the LLWS threat though winds at 2000 ft will remain around 40
knots through the evening. Gusts of 30-40 knots will continue
through tonight before diminishing to 20-30 knots Saturday
morning. Winds veer from southerly today to northwesterly by
Saturday morning.

Mid-clouds are leading to widespread VFR conditions today. After
00z, and especially after 04z increasing saturation behind a cold
front will lead to widespread low VFR cigs with periods of MVFR
possible. Scattered lake effect showers will develop near MKG,
AZO, BTL, and GRR tonight and continue into Saturday morning.
Showers could bring brief periods of MVFR cigs and visbys and
have included a PROB30 at MKG for this where better coverage of
showers will be.

&&

.MARINE...
Issued at 346 AM EST Fri Feb 28 2025

Gale warning continues for southwesterly gales possible this
morning, then northwesterly gales likely this evening/tonight.
Strong low-level jet but relatively stable thermal profile on the
warm side of the low-pressure system this morning may bring winds
near gale force. A period of westerly winds below gale force is
expected this afternoon, then northwesterly gales are likely this
evening into tonight in the vicinity of a cold front.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Wind Advisory until 11 PM EST this evening for MIZ037-043-050-
     056-064-071.
     Wind Advisory until 4 PM EST this afternoon for MIZ038>040-
     044>046-051-052-057>059-065>067-072>074.
MARINE...Gale Warning until 3 AM EST Saturday for LMZ844>849.

&&

$$

UPDATE...Meade
DISCUSSION...CAS
AVIATION...Thomas
MARINE...CAS