textproduct: Grand Rapids

KEY MESSAGES

- Breezy & Cooler Today; Isolated Shower Possible

- Dry Monday/Tuesday, Turning Wet Wednesday

DISCUSSION

Issued at 219 AM EDT Sun Aug 23 2026

- Breezy & Cooler Today; Isolated Shower Possible

We'll be west of a departing low pressure system today as cold air advection occurs over the region and boundary layer mixing should bring down 25-30 mph wind gusts to the surface. This cool NW breeze will only yield max temps in the upper 60s to low 70s today, below normal for the third week in August. CAMs are trying to spit out a few rogue showers today, mainly across central Lower MI, though these would be minor given decreasing low level moisture and pathetic ELs. Not expecting lightning in this activity today. Most areas will not get rained on.

- Dry Monday/Tuesday, Turning Wet Wednesday

The early week period looks tranquil with lighter winds as upper heights build and partly to mostly sunny skies will dominate. The next feature of interest is an upper trough that arrives Wednesday during peak heating. ECE ensemble members are sold on 1000+ MUCAPE across the region by afternoon/evening ahead of this feature, most of which should be realized as surface based instability at this point. GFS model soundings indicate moistening soundings during the afternoon and night hours Wednesday as surface dew points try to get into the 60s. Deep layer shear does not look very good with maybe 25 kts or so, thus only quasi-organized convection is likely, but trends will be monitored as we get closer. Best chance for rain looks to be 18z Wednesday through 06z Thursday. Can't rule out some leftover/lingering showers or scattered storms on Thursday mainly across mid Michigan and points east. Just depends on how fast the upper trough moves, but there is time to watch.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 630 AM EDT Sun Aug 23 2026

VFR is forecast for this TAF period. Breezy conditions expected at the terminals with gusts around 25 kts. Cloud bases around 5k ft this afternoon with only a widely scattered shower possible, most likely avoiding the terminals but will maintain some PROB30s to cover threats at A) AZO and BTL through ~14z and then B) LAN and JXN for diurnally driven showers possible from 18z-00z. There does not appear to be enough instability to warrant any mention of thunder.

MARINE

Issued at 219 AM EDT Sun Aug 23 2026

The forecast is unchanged for today with winds and waves remaining hazardous to small craft and hazardous swim conditions for the beaches. Expecting 4 to 6 ft for all areas with NW flow of 15 to 25 knots and some gusts to 30 knots possible. These winds and waves will not subside until this evening into tonight. After today, waves may reach 2-3 ft on Monday with a further diminishing into Tuesday.

GRR WATCHES/WARNINGS/ADVISORIES

MI...Beach Hazards Statement through this evening for MIZ037-043-050- 056-064-071. MARINE...Small Craft Advisory until 11 PM EDT this evening for LMZ844>849.