850
FXUS63 KGRR 291739
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
139 PM EDT Mon Jun 29 2026
.KEY MESSAGES...
- Non-zero chance for storms this morning
- Extreme heat starts to set in today
&&
.DISCUSSION...
Issued at 257 AM EDT Mon Jun 29 2026
- Non-zero chance for storms this morning
Still the potential for a few lightning strikes from the showers
currently over the area. The showers currently over Michigan give
our southern and eastern zones their best shot for rain/thunder
this morning.
The northern zones best chance comes from whether or not showers/storms
currently developing over Wisconsin make a southerly/southeasterly
turn and make it across Lake Michigan. Still enough instability to
keep us in the marginal risk for severe weather - with greatest
risk for hail and damaging winds. Models have all backed off
somewhat on bringing anything into the area at all...keeping
decaying storms in northern Lower...so this morning could also be
a complete bust. It certainly a wait and see what the next few
hours brings kind of a morning. Window for any storms today seems
to close around or shortly after noon.
- Extreme heat starts to set in today
The well advertised heat and humidity starts to build in today and
remains through at least the end of the week. High temperatures
should reach the upper 80s to lower 90s today across West
Michigan...making Monday the coolest day of the week. 90s to near
100 for highs Tuesday through Thursday are still expected with
heat index values of 105+. Lack of overnight relief from the heat
and humidity still expected with lows in the 70s for at least the
next 4 nights.
Its possible we might see a few record highs this week...but we
may be more likely to break a couple of record warm low
temperatures.
&&
.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 138 PM EDT Mon Jun 29 2026
VFR conditions are expected through the period. South winds will
become breezy during the afternoon but diminish a bit after
sunset.
&&
.MARINE...
Issued at 257 AM EDT Mon Jun 29 2026
Waves and winds will increase through the day with hazardous
swimming and boating conditions on Lake Michigan expected through
Tuesday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement through Tuesday evening for MIZ037-043-
050-056.
Extreme Heat Warning until 8 PM EDT Thursday for MIZ037>040-
043>046-050>052-056>059-064>067-071>074.
Air Quality Alert from midnight tonight to midnight EDT Tuesday
night for MIZ050-056-057-064-071.
MARINE...Small Craft Advisory until 8 PM EDT Tuesday for LMZ846>849.
&&
$$
DISCUSSION...Maczko
AVIATION...04
MARINE...Maczko
NWS GRR Office Area Forecast Discussion
