026
FXUS63 KGRR 190612
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
212 AM EDT Sun Jul 19 2026

.KEY MESSAGES...

- Dry With Smoke Today

- Showers and Storms Monday Night into Tuesday

- Dry Conditions Tuesday Night into Late Week

&&

.DISCUSSION...
Issued at 212 AM EDT Sun Jul 19 2026

- Dry With Smoke Today

Surface high pressure and a dry atmosphere will keep conditions dry
today as northerly post-cold frontal flow brings smoke back into the
area. According to Michigan`s Dept. of Environment, Great Lakes, and
Energy; The latest HRRR and RRFS smoke models show a band of smoke
moving southward through Southern Lower Michigan. This will create a
period of air conditions that will be Unhealthy for Sensitive Group
period tomorrow morning and afternoon. Latest model trends, along
with a pattern shift shows a reduction in smoke tomorrow evening.

- Showers and Storms Monday Night into Tuesday

Storms are expected to develop across the Upper Midwest Monday,
driven east by a shortwave and an attendant cold front. There are
questions given strong MLCIN as to the extent that these storms make
it across the lake. Regardless, given the dynamics rainfall is
likely. One thing we will have to watch is if a MCS can develop
along the cold front. If it does, there is a risk of damaging winds
given ample instability and shear. Thus the SPC`s marginal risk
across the area.

- Dry Conditions Tuesday Night into Late Week

Surface ridging and a dry moisture profile then return post cold-
front Tuesday Night and continue through the rest of the work week.
This looks to keep conditions dry. Highs fall into the 70s mid week
as 850mb temps fall into the single digits before climbing back into
the 80s by mid week.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 116 AM EDT Sun Jul 19 2026

Smoke so far has led to a mix of MVFR and VFR conditions.
Conditions favor a period of more solid MVFR twoards daybreak at
the low-level stability maximum. Confidence in conditions going
into Sunday afternoon is low. RRFS and HRRR guidance diverge on
the extent we can mix out smoke which determines whether
conditions improve to VFR or persist as MVFR. Winds aob 10 knots
are expected through the TAF period.

&&

.MARINE...
Issued at 212 AM EDT Sun Jul 19 2026

May have to extend the southern portion of the Small Craft
Advisory/Beach Hazards Statement for a few hours as waves at the
South Haven spotter bouy have been slow to fall. Winds and waves
then stay below hazardous levels during the day Sunday into the
start of Monday. Winds then increase ahead of and behind a cold
front later Monday into Tuesday. Thunderstorms are also possible
across the waters Monday Night.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement until 4 AM EDT early this morning for
     MIZ037-043-050-056-064-071.
     Air Quality Alert until midnight EDT tonight for MIZ037>040-
     043>046-050>052-056>059-064>067-071>074.
MARINE...Small Craft Advisory until 4 AM EDT early this morning for
     LMZ844>849.

&&

$$

DISCUSSION...Thomas
AVIATION...Thomas
MARINE...Thomas