800
FXUS63 KGRR 191035
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
635 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 slight 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 /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 635 AM EDT Sun Jul 19 2026
As anticipated, visibilities have fallen to solidly MVFR as we
approach daybreak due to smoke. GRR has already intermittenty
reached IFR with the RRFS-Smoke (which has been the best
performing guidance for this smoke outbreak) suggesting is likely
to continue for the next few hours. Expectation is that
visiblities will improve through the afternoon/evening favoring a
return to VFR as smoke concentrations decrease. Expect winds aob
10 kts from the northeast, backing to westerly then southerly
tonight.
&&
.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...Air Quality Alert until midnight EDT tonight for MIZ037>040-
043>046-050>052-056>059-064>067-071>074.
MARINE...None.
&&
$$
DISCUSSION...Thomas
AVIATION...Thomas
MARINE...Thomas
NWS GRR Office Area Forecast Discussion
