Marine Weather and Tide Forecast for Grand Beach, MI

DISCUSSION
Issued at 115 PM EDT Sun Oct 11 2026

Ridging through the column will provide a trend toward mostly clear skies and light winds tonight. This may allow for patchy fog/stratus development overnight into early Monday, especially over ne IN and nw OH where lows will likely dip below xover values.

Return flow and associated strong WAA on the backside of the exiting ridge will set the stage for breezy ssw winds and highs into the 80s Monday into Tuesday. A low amplitude, mid level impulse has consistently been modeled to track east through the Upper Midwest and central Great Lakes Monday night into Tuesday morning.
Associated theta-e advection and slight graze of mid level ascent support retaining low chances (10-30%) for a few showers/storms in the far north during this time.

A west to east oriented frontal zone tied to the aforementioned shortwave sags south into the area later Tuesday afternoon into Wednesday. An additional surge of deeper moisture and several upper level waves ejecting east out of an Intermountain West upper low likely activates the front with increasing rain/embedded thunder chances. Highest PoPs (60-70%) favor areas south of the US 30 corridor. Cooler, yet, still above normal temps otherwise into Wednesday.

Ensemble and deterministic model solutions continue to differ on whether a stronger storm system develops into the Great Lakes in response to potential phasing (or not) of southern and northern stream waves Thursday into Friday. This brings inherent uncertainty regarding precip chances and the magnitude of winds and CAA behind a cold front Friday into Saturday.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/
Issued at 1220 PM EDT Sun Oct 11 2026

Clouds from the remnants of Hurricane Isaias can be seen on satellite starting to depart from west to east. KFWA is still reporting IFR ceilings, but VFR ceilings are anticipated to return tonight as ceilings gradually rise over the next several hours. Clouds will be completely out of the area by 00-03Z. Winds will be light and variable through this evening and overnight.
With moisture lingering near the surface alongside light winds and clear skies overnight, patchy dense fog is expected to develop. For now, have kept MVFR visibilities at KFWA but I wouldn't be surprised if visibilities drop to IFR by early Monday morning depending on how dense the fog is. NBM probabilities show 20-30% chances for visibilities less than 2 miles.

IWX WATCHES/WARNINGS/ADVISORIES
IN...None.
OH...None.
MI...None.
MARINE...None.