210
FXUS63 KGRR 071801
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
201 PM EDT Tue Jul 7 2026
.KEY MESSAGES...
- Slow moving front brings rain, storms late week
- Upper High builds in early next week
&&
.DISCUSSION...
Issued at 201 PM EDT Tue Jul 7 2026
- Slow moving front brings rain, storms late week
Quasi-zonal flow regime this week with upper height falls
attending a slow-moving cold front sagging south through the Great
Lakes. We will see chances for showers and thunderstorms from
Wednesday night through Friday as the front becomes almost
parallel to the flow.
By Thursday, training of storms could result in minor flooding but
in most areas rainfall should be beneficial rather than excessive.
Severe weather chances are marginal Wednesday night with limited
instability and deep layer shear.
- Upper High builds in early next week
The rains should end across the southern zones over the weekend as
the front sags south then large scale subsidence and drying begins
with an upper high across the Northern Plains edging into Lower
Michigan. Expect warm and dry for early next week before heights
fall as an upper trough amplifies across eastern Canada.
&&
.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 100 PM EDT Tue Jul 7 2026
VFR conditions are ongoing thanks to the dry airmass with a few
clouds around 4-6kft. Tonight, patchy ground fog is possible with
the greatest chance at JXN which climatologically is our most
likely site for restrictions. MVFR is favored if fog does form.
However, given low confidence at all terminals except JXN, have
kept restrictions out for now. Look for winds below 10 knots from
the west/northwest Today and Wednesday.
&&
.MARINE...
Issued at 201 PM EDT Tue Jul 7 2026
Fairly tranquil weather this week except for the possibility of
thunderstorms with gusty winds and heavy downpours Wednesday night
into Thursday morning. Wind direction will be frequently changing
with north winds tonight going south on Wednesday then north again
on Thursday and Friday, but generally remaining at or below 15
knots.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Ostuno
AVIATION...Thomas
MARINE...Ostuno
NWS GRR Office Area Forecast Discussion