734
FXUS63 KGRR 031851
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
251 PM EDT Sun May 3 2026
.KEY MESSAGES...
- Marginal Risk Severe on Monday
- Cool with Frost/Freeze Potential This Week
&&
.DISCUSSION...
Issued at 250 PM EDT Sun May 3 2026
- Marginal Risk Severe on Monday
Southwest flow with modest moisture return and elevated instability
ahead of an advancing cold front is expected to touch off
scattered showers and thunderstorms late Monday afternoon and
evening. Deep layer shear of 35 knots will aid the cause. Any
sustained updrafts could produce hail and strong winds are also a
threat given DCAPE resulting from evaporation of precip in a dry
adiabatic sub cloud layer. The threat diminishes after midnight
as the cold front moves through.
- Cool with Frost/Freeze Potential This Week
The front stalls across the Ohio Valley with a surface low
tracking northeast along the front. At this point it looks like
the precip shield stays east of Lower Michigan. Frost/Freeze
conditions will return for Tuesday and Wednesday nights
Showers are possible on Thursday afternoon and evening as a
shortwave trough and vorticity maximum moves though and model
soundings show wet-bulb zero heights not far off the surface
across the northern zones, so graupel or wet snow is possible
there. Frost/Freeze potential lingers into next weekend and beyond
as a cold northwest flow regime continues.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 150 PM EDT Sun May 3 2026
VFR is expected to continue with ceilings mostly above 5,000 feet
as scattered rain showers pass through this afternoon. Clouds go
scattered to few tonight. Gusty southwest winds this afternoon
relax a little and become south overnight, then become gusty
from the southwest again Monday.
&&
.MARINE...
Issued at 250 PM EDT Sun May 3 2026
No changes to the SCA. There will be a brief lull tonight then
another SCA will be needed for Monday into Monday night.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until midnight EDT tonight for LMZ844>849.
&&
$$
DISCUSSION...Ostuno
AVIATION...CAS
MARINE...Ostuno
NWS GRR Office Area Forecast Discussion
