169
FXUS63 KGRR 181805
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
205 PM EDT Sun Oct 18 2026
.KEY MESSAGES...
- Tranquil and Relatively Warm This Week
&&
.DISCUSSION...
Issued at 205 PM EDT Sun Oct 18 2026
- Tranquil and Relatively Warm This Week
Minimal weather concerns this week as there will be a tendency
for high pressure over the Great Lakes region and beyond much of
the time. A very El-Nino-looking split upper level jet is over
North America this week, and Michigan will be under weak flow
through Wednesday.
High temperatures will generally reside in the mid to upper 60s
while the 30-year normal highs slip into the upper 50s. With the
mostly clear skies and light winds, nightly lows will be closer to
normal, between the mid 30s and mid 40s. Areas of fog Tuesday
morning and Wednesday morning are possible. After today, all
ensemble members are very light on winds, until there is just a
minor uptick Thursday and and into the weekend when a couple of
weak troughs ripple through the pattern. The lack of moisture and
lift wouldn`t favor much more than a chance of sprinkles.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 135 PM EDT Sun Oct 18 2026
Very dry air and VFR conditions will persist at all West Michigan
TAF sites, thanks to high pressure over the northeastern CONUS
and eastern Great Lakes.
SW breezes will continue through the TAF period, though the
gustiness being observed this afternoon at some sites should
diminish this evening /with the exception of MKG, where gusts to
around 20kt will persist along the Lake MI shoreline/. As a very
weak surface front sags into northern Lower MI Monday, the
pressure gradient will weaken so the SW winds will be lighter to
start the work week.
&&
.MARINE...
Issued at 205 PM EDT Sun Oct 18 2026
Wind and wave observations in the nearshore have been firmly in
small craft advisory territory with gusts 25 to 30 knots, waves
3-5 feet around South Haven, and greater than 6 feet north of
Holland. Gale force gusts have so far only been in northern Lake
Michigan and should remain that way. Winds weaken gradually
tonight and conditions will improve south of South Haven, but
waves may take until later Monday morning to come down between
Holland and Manistee. After that, no concerns for the next several
days.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 11 PM EDT this evening for LMZ844.
Small Craft Advisory until 11 AM EDT Monday for LMZ845>849.
&&
$$
DISCUSSION...CAS
AVIATION...Smith
MARINE...CAS
NWS GRR Office Area Forecast Discussion
