261
FXUS63 KGRR 191745
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
145 PM EDT Wed Aug 19 2026

.KEY MESSAGES...

- Low clouds and fog possible this morning, then partly cloudy

- Rainfall chances return Friday

&&

.DISCUSSION...
Issued at 259 AM EDT Wed Aug 19 2026

- Low clouds and fog possible this morning, then partly cloudy

Given the widespread precipitation we received last night, light
winds, and decreasing clouds, we can expect the development of low
clouds and perhaps fog early this morning. The extent and
severity of possible fog remain in question, but the best guess
now is that it would be patchy and only locally dense. Please see
the Aviation section of this discussion for additional details.
Any fog that manages to develop should dissipate relatively
quickly after sunrise this morning.


- Rainfall chances return Friday

As noted previously, we will be predominantly dry Wednesday and
Thursday. An approaching upper PV max approaches the western Great
Lakes Thursday night and guidance brings precipitation associated
with this disturbance into the area beginning early Friday. Going
into the weekend, we remain under the influence of broad longwave
troughing. Deterministic models had been consistently hinting at
the development of a vertically stacked low somewhere over the
western Great Lakes, but now the favored location for this to
happen is east of Lower MI, more towards the central Great Lakes.
This would result in a drier weekend forecast for our area than
previously thought.

Not surprisingly, this forecast remains very much a moving target,
especially when dealing with cutoff lows, so the general takeaway
for now is to cautiously plan for generally unsettled conditions
this weekend. That said, it`s reasonable to expect that the next
couple of model cycles in the coming day or so will bring better
consensus/clarity for the weekend forecast.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 145 PM EDT Wed Aug 19 2026

VFR conditions will generally prevail this afternoon across West
Michigan, with only scattered 3-4kft CU anticipated. The
exception will be at BTL/LAN/JXN, where occasional broken MVFR
ceilings just below 3kft will be possible through roughly 20-21Z.
Otherwise, expect CU to dissipate this evening, with only some
patchy mid/high clouds expected thereafter, mainly along the I-94
corridor /AZO-BTL-JXN/. Mainly clear skies /VFR wx/ expected
Thursday.

Winds will remain light through the TAF period. Generally W-NW
flow this afternoon will veer to NE by late tonight and continue
Thursday.

&&

.MARINE...
Issued at 259 AM EDT Wed Aug 19 2026

The highest reported waveheights in the nearshore area at this
time is at the Ludington buoy, which is down to 3.3 feet after
reaching 3.9 feet early Tuesday night. Based on buoy trends and
WW3 guidance, have cancelled the Small Craft Advisory early. The
next threat for hazardous waves arrives Friday afternoon across
our northern zones in response to persistent and moderately strong
winds from the south-southwest.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.

&&

$$

DISCUSSION...TJT
AVIATION...Smith
MARINE...TJT