textproduct: Grand Rapids

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.