722
FXUS63 KGRR 230742 CCA
AFDGRR
Area Forecast Discussion...CORRECTED
National Weather Service Grand Rapids MI
342 AM EDT Fri Oct 23 2026
.KEY MESSAGES...
- Warm End to the Week with Morning Fog
- Cooler Monday-Tuesday Then Becoming Unsettled
&&
.DISCUSSION...
Issued at 326 AM EDT Fri Oct 23 2026
- Warm End to the Week with Morning Fog
Tranquil and relatively warm weather persists through Sunday
under a pronounced upper level ridge and large area of high
pressure. Ensemble systems are practically unified with the
temperature forecast through Sunday, with highs about 10 degrees
above normal, in the mid 60s to around 70.
True to the season, areas of morning fog has been a challenge
much of this week. For this morning, patchy dense fog has
developed between Whitehall and Ludington, while the air off Lake
Huron invading Central Michigan has been more low stratus instead
of dense fog, at least so far. Patchy fog will continue to be a
possibility with radiational cooling in areas under clear skies
through daybreak. There is another signal among the REFS member
models for areas of fog to develop again tonight in much of
central to south- central Michigan.
- Cooler Monday-Tuesday Then Becoming Unsettled
With a flattening of the ridge early next week, a cold front
associated with a low pressure system tracking from the lee of the
Canadian Rockies to Hudson Bay will likely bring cooler air into
Michigan, and probably without much precip. Ensembles have more
spread in temperature solutions for Monday-Tuesday, but the
majority do bring cooler air with highs within the 50s to mid 60s,
which is closer to normal.
There is also some signal for temperatures to rebound into the
60s again midweek, ahead of a low that would track from the Pac NW
through the northern Plains toward the Great Lakes. This low
could bring the next best chance for about a quarter inch of
rainfall around Thursday, though for now we are running with PoPs
around 30 percent.
Thereafter, ensembles diverge greatly regarding the positions of
the large-scale northern stream trough and ridge over central
North America. So this means low confidence in the forecast (for
now) for the end of next week, as model solutions really contain
all combinations of warm and cold, dry and wet... but not cold
enough for snow yet.
&&
.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 115 AM EDT Fri Oct 23 2026
Fog this morning is the only weather concern. Currently there is
patchy LIFR fog from Muskegon (MKG) north toward Ludington (LDM),
and widespread LIFR ceilings and/or visibility (low stratus
clouds or fog) via moist air flowing in off Lake Huron into
Central Michigan. Mount Pleasant (MOP) and Alma (AMN) are
currently affected, and also much of eastern Lower Michigan. These
clouds/fog are spreading west and will likely reach Lansing (LAN)
and Jackson (JXN) in the next few hours, and may reach Grand
Rapids (GRR) and Battle Creek (BTL) by daybreak / 11 Z. IFR may
hang around until 14 Z, based on previous fog events earlier this
week.
&&
.MARINE...
Issued at 326 AM EDT Fri Oct 23 2026
Areas of fog this morning may affect the harbors and portions of
the nearshore, mainly north of Grand Haven. Today will have light
winds and low waves. South winds 10-20 knots on Saturday will
build waves to 2 to 4 feet north of Whitehall, persisting into
Sunday morning.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Dense Fog Advisory until 10 AM EDT this morning for MIZ037-039-
040-043.
MARINE...Dense Fog Advisory until 10 AM EDT this morning for LMZ848-849.
&&
$$
DISCUSSION...CAS
AVIATION...CAS
MARINE...CAS
NWS GRR Office Area Forecast Discussion
