textproduct: Grand Rapids

KEY MESSAGES

- Showers possible through far southern Michigan tomorrow

- Fair, dry with warming weather into next week

DISCUSSION

Issued at 255 PM EDT Tue Sep 22 2026

- Showers possible through far southern Michigan tomorrow

Michigan currently is at an impasse between two systems. A low, cycling along the Iowa, Illinois and Wisconsin borders is bringing southerly moisture northward into lower michigan. A large upper level high remains entrenched over Ontario and Quebec. Michigan lies in between these systems. The pressure gradient along their boundary is creating gusty surface winds out of the east. Expect these winds to continue through the evening, dampening briefly overnight, before strengthening again tomorrow. The upper level high pressure will shift eastward as a ridge of high pressure builds front the south. This will drive the previously mentioned low to the south east. As it moves east there is a slight chance that some of the precip bands on the periphery will infiltrate Michigan with a slight chance of bringing light rain to the southern tier or two of Michigan tomorrow afternoon. Latest models continue to shift the low southward, so these precip chances continue to dwindle.

- Fair, dry with warming weather into next week

The models are in fair agreement through the mid to long range. The ridge building from the south should become a full fledged rex block high late this week, into the weekend. The low will continue to advect eastward and given the latest trends is tracking to close off as it begins its trek up the northeastern seaboard. The high pressure will simultaneous keep this low from retrograding, and stop an upper level wave from intruding into the Great Lakes region.

The below normal temperatures will slowly warm through the weekend, with above normal temperatures, peaking into the low 70s, are trending into next week.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 108 PM EDT Tue Sep 22 2026

Expecting mostly VFR this afternoon with cloud layers around 3,500 feet and 20,000 feet, and northeast winds gusting up to 20 or 25 knots. Can't rule out some temporary 3,000 ft ceilings at JXN this afternoon. Tonight, cloud cover should increase especially around AZO, BTL, and JXN, and conditions could slip into MVFR at times with clouds between 3,000 and 4,000 feet. Also expect about 20 knots of LLWS between 1,000 feet and ground between 01 and 12 Z, with winds at 1,000 feet about 08030KT.

MARINE

Issued at 254 PM EDT Tue Sep 22 2026

Strong offshore winds will continue the the evening hours. waves remain calm and should continue through Thursday, before winds settle down a bit. The offshore component should keep the winds just below criteria. High pressure will build over the region late this week and through the weekend which will create lighter winds by Friday.

GRR WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...None.