textproduct: Grand Rapids

KEY MESSAGES

- Extreme Heat Today Through At Least Thursday

- Chances for Storms Later in the Week

DISCUSSION

Issued at 308 AM EDT Tue Jun 30 2026

- Extreme Heat Continues Through At Least Thursday

No change for the expectations of today being the first of three straight days with very dangerous heat and humidity. Highs in the 90s with lows in the upper 70s will be common Tuesday through Thursday with heat index values during the day into the 100s and in the nighttime period in the mid to upper 80s. Friday is likely to see some relief as the upper ridge weakens...though highs Friday may only be about 5 degrees or less cooler than the rest of the week. A little more relief (though it still will be hot) comes over the holiday weekend when high temperatures in the mid 80s will be common.

- Chances for Storms Later in the Week

Still expecting a series of shortwaves to try and weaken the ridge over us the rest of the week. Some of these waves could bring showers/thunderstorms to southern Lower Michigan. Generally the greater severe risk will remain over the Upper Peninsula and northern lower...but instability is good enough over southern lower to keep a non-zero severe threat. Hard to pick which days or timeframes are best for storms and/or any possible severe weather...though the severe risk does creep a little further south each day through Thursday.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 646 AM EDT Tue Jun 30 2026

Winds will become a little gusty today with gusts over 20kts from early this afternoon into early this evening. VFR conditions expected through the TAF period.

MARINE

Issued at 308 AM EDT Tue Jun 30 2026

Small Craft Advisory and Beach Hazard Statements continue through today. Gusty southwest winds will develop by early afternoon and waves should increase for most through the evening. Greatest risk for swimmers will be south of south piers where extra caution should be taken in choppier conditions.

GRR WATCHES/WARNINGS/ADVISORIES

MI...Beach Hazards Statement through this evening for MIZ037-043-050- 056. Extreme Heat Warning until 8 PM EDT Thursday for MIZ037>040- 043>046-050>052-056>059-064>067-071>074. Air Quality Alert until midnight EDT tonight for MIZ050-056-057- 064-071. MARINE...Small Craft Advisory until 8 PM EDT this evening for LMZ846>849.