351
FXUS63 KGRR 081047
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
647 AM EDT Fri May 8 2026
.KEY MESSAGES...
- Northwest Flow Regime Continues
&&
.DISCUSSION...
Issued at 257 AM EDT Fri May 8 2026
- Northwest Flow Regime Continues
Upper troughing across the Great Lakes will persist into next
week. Temperatures will run cooler than normal with Frost/Freeze
potential on Saturday, Sunday and Monday nights. Clipper type
lows will occasionally bring showers in a northwest flow regime.
A shortwave trough moves through tonight with scattered showers
into Saturday morning. The pattern repeats for Tuesday into
Tuesday night. The Tuesday low should have deeper moisture to
work with, but is moving fast enough to limit the chances of
excessive rainfall.
&&
.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 647 AM EDT Fri May 8 2026
VFR conditions today and much of tonight with southwest winds AOB
10 knots. MVFR conditions move in late tonight, and could see
ceilings approaching IFR by 12Z Saturday across southern Lower
Michigan.
&&
.MARINE...
Issued at 257 AM EDT Fri May 8 2026
Held off on a SCA for tonight as conditions will be marginal but
it is possible that south/southwest winds will gust to 25 knots
this evening north of Whitehall where waves could also top 4 feet,
especially around Big and Little Sable Points.Conditions improve
Saturday night and Sunday as pressure gradient relaxes.
&&
.FIRE WEATHER...
Issued at 257 AM EDT Fri May 8 2026
Lowered NBM dew points for today given soundings showing mixing
heights rising to 7500 feet. This gives Min RH around 25 percent
this afternoon. Deep mixing will yield winds of 20 knots at the
surface as well, so we will have to monitor for RFW criteria being
reached this afternoon.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Frost Advisory until 9 AM EDT this morning for MIZ037-038-
043>046.
Freeze Warning until 9 AM EDT this morning for MIZ039-040.
MARINE...None.
&&
$$
DISCUSSION...Ostuno
AVIATION...Ostuno
MARINE...Ostuno
FIRE WEATHER...Ostuno
NWS GRR Office Area Forecast Discussion