198
FXUS63 KGRR 211733
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
133 PM EDT Sun Jun 21 2026
.KEY MESSAGES...
- Rain Chances Tonight and Wednesday
&&
.DISCUSSION...
Issued at 155 AM EDT Sun Jun 21 2026
- Rain Chances Tonight and Wednesday
The Great Lakes region will continue to be in a fast quasi-zonal
flow regime on the southern edge of persistent upper troughing
across eastern Canada this week. This will keep temperatures
below normal with fast-moving shortwave troughs bringing the
chance for rain tonight and again on Wednesday.
The best chance for rain tonight will be across southern Lower
Michigan as low pressure tracks across northern Indiana and Ohio.
An area of mid-level frontogenetic forcing brings steady rain
across the I-94 corridor with QPF close to an inch by the time
the rain ends on Monday. There will be a sharp gradient to the
north with around a quarter inch along I-96 and less than a tenth
of an inch north of there.
A weaker low follows for Wednesday in northwest flow and precip
amounts will probably be less than a quarter inch.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 131 PM EDT Sun Jun 21 2026
Cloud bases will lower throughout the afternoon as rain moves
toward the terminals. Light steady rain and MVFR/IFR ceilings are
expected as the evening progresses through the overnight hours.
Ceilings will improve Monday morning as low pressure moves east
and takes the rain with it.
&&
.MARINE...
Issued at 156 AM EDT Sun Jun 21 2026
Fairly tranquil conditions today then winds and waves will
increase tonight as low pressure passes just south of Lake
Michigan. A SCA will be needed for Monday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Ostuno
AVIATION...04
MARINE...Ostuno
NWS GRR Office Area Forecast Discussion