textproduct: Grand Rapids

KEY MESSAGES

- Dry weather through Thursday night with frost possible tonight

- Rain back in the forecast Friday into the weekend

- Warmer and mainly dry early next week

DISCUSSION

Issued at 358 AM EDT Wed May 20 2026

- Dry weather through Thursday night with frost possible tonight

Surface high pressure will bring dry weather today through Thursday night. Clouds will gradually erode today with partly cloudy skies expected tonight. We may need a Frost Advisory tonight across Central Lower Michigan, but after coordination with other offices decided to hold off on the advisory/warning decision until later today as there may be a good amount of high clouds around yet which would affect low temperatures. In addition, there is a fair amount of wind in the lowest 2,000 feet. A partly cloudy day is expected on Thursday with mid and high clouds streaming in from the west. It will be cooler than normal today and Thursday with highs in the 50s and 60s today warming to the 60s on Thursday. Normal highs are around 70.

- Rain back in the forecast Friday into the weekend

Rain returns to the forecast on Friday and especially for Friday night and Saturday. A shortwave trough aloft lifts from the Southern Plains states into the Great Lakes for Friday night and Saturday with an upper trough then swinging through on Sunday. A healthy surge of moisture comes in on a low level jet Friday night and Saturday which is when we should have the highest concentration of showers and thunderstorms. This time frame will essentially be affected by a warm front of sorts with a cold front moving through on Sunday. Bottom line is the weather will be a bit unsettled during this time.

- Warmer and mainly dry early next week

Warmer and drier weather is expected early next week with zonal flow aloft trending towards ridging. At the surface, ridging will be in place. High temperatures will be warming into the 70s to near 80 degrees.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 648 AM EDT Wed May 20 2026

There are some MVFR ceilings over portions of Lower Michigan drifting south from I-96 at 11z. These ceilings should affect most of the TAF sites this morning, with MKG being the exception. By this afternoon we are expecting VFR weather to prevail which will continue into tonight. North winds can be expected today at 7-12 knots. There will be occasional gusts into the 15-20 knot range.

MARINE

Issued at 358 AM EDT Wed May 20 2026

Our typical advancing high scenario presents itself today on the first day of the Surf Zone Forecast season. A high building into the Great Lakes from the northwest winds increase northerly winds down the shoreline through an enhanced pressure gradient along the lakeshore. The combination of the high building in and thermal affects (troughing developing over the Lower Peninsula) due to a thinning of the low clouds produces stronger winds down the shoreline. The winds can be seen in the HRRR guidance. While we are not expecting many swimmers today (buoy water temps are in the lower 50s) we will still issue a Beach Hazard Statement as the season has begun. A corresponding Small Craft Advisory will be in effect as well, both running from 100pm into tonight. Winds go offshore late tonight and into Thursday which will lead to improving conditions.

GRR WATCHES/WARNINGS/ADVISORIES

MI...Beach Hazards Statement from 1 PM EDT this afternoon through late tonight for MIZ056-064-071. MARINE...Small Craft Advisory from 1 PM this afternoon to 2 AM EDT Thursday for LMZ844>846.