534
FXUS63 KGRR 101910
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
310 PM EDT Sun May 10 2026
.KEY MESSAGES...
- Frost/Freeze Next Couple Nights
- Rain and Thunderstorm Chances Tue-Wed and Late Week
&&
.DISCUSSION...
Issued at 310 PM EDT Sun May 10 2026
- Frost/Freeze Next Couple Nights
Temperatures this morning were a little colder than forecast
under crystal clear skies. Tonight and Monday night will again
have frost/freeze potential, widespread in Central Michigan and in
the typically colder areas farther south. The NBM mean low
temperatures for tonight have trended slightly warmer the past
couple cycles, but still plenty cold to maintain the threat of
impacts. Confidence in the southern frost threat tonight is just a
little lower due to patches of midlevel clouds that should linger
later in the night. Another chance of frost is possible in
Central Michigan Wednesday night before the larger pattern breaks
toward being warmer.
- Rain and Thunderstorm Chances Tue-Wed and Late Week
An Alberta Clipper low pressure system sliding through the region
Tue-Wed will bring rain showers starting Tuesday morning.
Elevated instability will increase later in the day Tuesday then
persist into early morning Wednesday, so the thunderstorm chance
will be confined to that time frame. The amount of instability
looks to be fairly meager and the lower atmosphere will tend to be
stable, thus reducing the chance of severe weather.
The cooler-than-normal pattern so far this month will trend
warmer late in the week with the demise of the Greenland blocking
high and Quebec low. The return of warmer temperatures and better
moisture along with progressive shortwave troughs over the region
will result in thunderstorm chances Friday and through the weekend
to early next week. Members within each global ensemble system
are not settled on which particular day or days are most favored
at this time.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 143 PM EDT Sun May 10 2026
VFR conditions are highly likely at all terminals through 00Z this
evening (95 percent chance) and through 06Z tonight (90 percent
chance). Wind gusts mostly from the west and northwest are expected
to diminish around 00Z this evening with winds eventually becoming
light to calm. A cold surface airmass early Monday morning could
result in the colder air draining to lower elevations, resulting
in light winds having a direction more associated with local
topography than with synoptic forcing.
&&
.MARINE...
Issued at 310 PM EDT Sun May 10 2026
Expecting 1 to 3 ft waves through Monday, then a small craft
advisory will likely be needed Tuesday as south winds strengthen
to 30 knots (perhaps approaching gale force near the Sable
points). Hazardous conditions with northwest winds will continue
into Wednesday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Freeze Warning from midnight tonight to 8 AM EDT Monday for
MIZ037>040-043>046.
Frost Advisory from midnight tonight to 8 AM EDT Monday for
MIZ050>052-056>059-064>067-071>074.
MARINE...None.
&&
$$
DISCUSSION...CAS
AVIATION...TJT
MARINE...CAS
NWS GRR Office Area Forecast Discussion
