textproduct: Grand Rapids

KEY MESSAGES

- Low clouds and fog possible this morning, then partly cloudy

- Rainfall chances return Friday

DISCUSSION

Issued at 259 AM EDT Wed Aug 19 2026

- Low clouds and fog possible this morning, then partly cloudy

Given the widespread precipitation we received last night, light winds, and decreasing clouds, we can expect the development of low clouds and perhaps fog early this morning. The extent and severity of possible fog remain in question, but the best guess now is that it would be patchy and only locally dense. Please see the Aviation section of this discussion for additional details. Any fog that manages to develop should dissipate relatively quickly after sunrise this morning.

- Rainfall chances return Friday

As noted previously, we will be predominantly dry Wednesday and Thursday. An approaching upper PV max approaches the western Great Lakes Thursday night and guidance brings precipitation associated with this disturbance into the area beginning early Friday. Going into the weekend, we remain under the influence of broad longwave troughing. Deterministic models had been consistently hinting at the development of a vertically stacked low somewhere over the western Great Lakes, but now the favored location for this to happen is east of Lower MI, more towards the central Great Lakes. This would result in a drier weekend forecast for our area than previously thought.

Not surprisingly, this forecast remains very much a moving target, especially when dealing with cutoff lows, so the general takeaway for now is to cautiously plan for generally unsettled conditions this weekend. That said, it's reasonable to expect that the next couple of model cycles in the coming day or so will bring better consensus/clarity for the weekend forecast.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 644 AM EDT Wed Aug 19 2026

Even if not explicitly stated at all of the terminals, there will be an estimated 40 percent chance of brief IFR ceiling or visibility restrictions between 12Z and 13Z.

Conditions will be a little slower to improve in general this morning compared to what was advertised with the 06Z package, with fuel alternate ceilings persisting until 15Z at some locations. Confidence is still reasonably high (85 percent chance) that VFR conditions will be in place areawide by 16Z. After that, VFR conditions should continue through at least 00Z tonight.

MARINE

Issued at 259 AM EDT Wed Aug 19 2026

The highest reported waveheights in the nearshore area at this time is at the Ludington buoy, which is down to 3.3 feet after reaching 3.9 feet early Tuesday night. Based on buoy trends and WW3 guidance, have cancelled the Small Craft Advisory early. The next threat for hazardous waves arrives Friday afternoon across our northern zones in response to persistent and moderately strong winds from the south-southwest.

GRR WATCHES/WARNINGS/ADVISORIES

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