textproduct: Grand Rapids

KEY MESSAGES

- Showers and storms today

- Dry weekend then another chance for showers and storms on Monday

- Cooling off through the upcoming work week

DISCUSSION

Issued at 400 AM EDT Fri Apr 24 2026

- Showers and storms today

Showers and storms remain in the forecast today. The precipitation should be on the lighter side and a bit more scattered this morning as the precipitation is coming in, in a decaying state. The moisture push is healthy and so is the low level jet, so we should see at least some precipitation this morning. Surface dew points will rise to around 60F this morning with PWAT values surging from 0.80 inches at 2AM to 1.3 inches at 11AM. The 850MB LLJ this morning is a very respectable 30-40 knots. Instability (MUCAPE) is weak, generally less than 500 j/kg this morning with surface based LIs that are positive. So, while we should see showers move into the forecast area this morning, there should not be much in the way of thunder.

This afternoon, the moisture will be in place, but the 850MB jet backs off to 25-30 knots. The 500mb mid level jet is also decreasing in speed through the course of the day which in turn keeps deep layer shear less than 25 knots. Bottom line we will see showers move through the area today with thunderstorm chances increasing this afternoon especially from Highway 131 to the east. Threat for severe looks low despite an uptick in instability to around 1,000 j/kg this afternoon in the east towards MOP, LAN and JXN.

- Dry weekend then another chance for showers and storms on Monday

The weekend looks dry with surface ridging holding on in the wake of the a cold frontal passage this afternoon and evening. Focus then shifts to a low pressure system moving our direction from the plains. The GFS is a little quicker bringing in some precipitation Monday afternoon, whereas the ECWMF holds precipitation off until Monday night. This is another surge of 60F dew points and PWAT values that will be a bit higher than today's system to around 1.5 inches. At this point timing does not look great for stronger storms, coming through Monday night. Instability is not high with MUCAPE values remaining below 1,000 j/kg. We have high pops (90 pct) on Monday night with the system moving east on Tuesday.

- Cooling off through the upcoming work week

The rest of next week will feature upper troughing and cooler weather. Highs mid to late next week look to be back in the 50s, which is slightly below normal for this time of year. We should be mainly dry, but with an upper trough in place in the spring diurnal showers are certainly possible.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 657 AM EDT Fri Apr 24 2026

A cold front will move through Southwest Lower Michigan this afternoon and evening. Rain showers will be possible this morning, but become more numerous this afternoon and evening. Thunderstorms will be possible especially from BTL, LAN and JXN. Conditions should largely stay VFR today. MVFR and even IFR ceilings will develop tonight in the wake of the front. Winds will become gusty from the southwest today at 10-20 knots with a few higher gusts.

MARINE

Issued at 400 AM EDT Fri Apr 24 2026

We are expecting conditions to remain below advisory levels through the weekend. Winds this morning will be southerly and likely remaining in the 10-20 knot range. This afternoon behind a cold frontal passage which veer to the northwest and north. Speeds should remain in the 10-20 knot range as well. North winds will increase some Saturday afternoon and night which will likely bump the waves up to 2-4 feet for a time.

GRR WATCHES/WARNINGS/ADVISORIES

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