textproduct: Grand Rapids

KEY MESSAGES

- Brief Window for Strong to Severe Thunderstorms Today

- Below Normal Temperatures Friday and Saturday

- Potentially Unsettled Weather Next Week

DISCUSSION

Issued at 225 AM EDT Thu Mar 26 2026

- Brief Window for Strong to Severe Thunderstorms Today

There is a brief window where we could see strong to severe thunderstorms between 12PM to 5PM. This will be largely south of I-96 with the best chances (SPC Slight Risk) along and south of I-94. The 700mb jet moves in early this afternoon providing some mid level lift along with elevated instability. With the stronger winds aloft hail will be the primary concern. The wind and tornado threat will largely be south of the area. This is due to the cold front moving through this morning and afternoon. Areas along and south of I-94 have a brief window for any surface based storms between noon and 5PM before the cold front moves through. Instability however is limited and looking at the Max SBCAPE values on the HREF, there a tight gradient along I-94. Overall odds are low, hence the SPC Day 1 outlook adjustment shifting the wind and tornado threat south of the area.

Otherwise expect some scattered showers as the front shifts south this morning and afternoon. Winds will pick up from the north behind the front this afternoon and evening with gusts around 20 to 25 mph. Dry conditions return across the area this evening.

- Below Normal Temperatures Friday and Saturday

Colder temperatures move in for Friday with 925 mb temperatures around 6 to 8 C below zero. Highs are only expected to be in the mid to upper 30s with some spots potentially hitting 40. Colder temperatures are expected Friday night with lows in the mid teens to mid 20s. A shortwave trough moving through Friday night may have enough moisture for some snow, any accumulations would be light. Warm air advection brings slightly warmer temperatures for Saturday with highs in the upper 30s to mid 40s.

- Potentially Unsettled Weather Next Week

Global ensemble data is in good agreement regarding a synoptic pattern change by the early to middle portion of next week. ECE/GEFS/CMC ensemble mean 500mb heights and vorticity indicate a shift from a dominant ridge across the SW U.S. to an orientation more across the SE U.S. as deep upper troughing begins to set up across the West Coast. This places the Great Lakes in a region of deeper southwest flow and already there are signs of anomalous PWAT values surging into the region by Tuesday or Wednesday. Depending on frontal positioning, this could lead to a rather wet pattern heading into the midweek period.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 636 AM EDT Thu Mar 26 2026

VFR conditions are expected this morning before ceilings gradually lower to MVFR as the front moves south and scattered showers develop. A brief period of IFR ceilings is possible especially toward JXN where there is a better potential for thunderstorms. Depending on how fast the front moves through lightning could remain south of the terminals. There will be a potential for large hail between 17Z to 21Z but the wind and tornado risk is expected to remain south of the area. Behind the front winds will shift to the north, northeast. Gusts toward 20 knots is expected this evening. Ceilings will gradually lift late tonight into Friday morning.

MARINE

Issued at 225 AM EDT Thu Mar 26 2026

A brief lull in Small Craft Advisory conditions is expected today before north to northeast winds pick up behind the front late this afternoon into tonight. Even with the offshore flow, waves are expected to rise to 3 to 6 feet. Waves may linger into Friday morning before subsiding.

Scattered showers are also expected along the front, although the potential for thunderstorms is low with the best chances south of South Haven this afternoon.

Winds Friday turn to the northwest and increase briefly during the afternoon. We could see Small Craft Advisory conditions return for areas south of Grand Haven for a few hours before sunset Friday.

GRR WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...Small Craft Advisory from 4 PM this afternoon to 6 AM EDT Friday for LMZ844>849.