Marine Weather and Tide Forecast for Grosse Pointe Park, MI

AVIATION

An upper level short wave and associated sfc low will track from Upper Mi early this morning into Se Mi and ern Ontario late this morning and early afternoon. Strengthening SW wind fields atop a shallow nighttime stable layer will remain supportive of low level wind shear during roughly the 08Z to 14Z time frame before daytime mixing transitions conditions to gusty winds at the surface. Ample dry air in the low levels will warrant low probabilities for rain showers this morning as the upper wave advances across the region, with ceilings remaining high (VFR) based. As the surface low and associated cold front depart southeast of the area this afternoon, shallow post frontal cold air and moisture advection will result in an expanding MVFR based stratus deck.

DTW THRESHOLD PROBABILITIES...

* Low in ceilings aob 5000 feet this morning. High this afternoon and tonight.

PREV DISCUSSION
Issued at 229 PM EDT Thu Mar 19 2026

Record breaking high amplitude ridge over the western United States will result in a northwest flow regime for the Great Lakes region Friday and this weekend. Generally looking at minor forecast concerns over the coming days with the most pertinent of challenges being the swings in the temperature forecast locally with the baroclinic zone wavering in vicinity of Southeast Michigan.

Quiet weather with a few breaks in the clouds early this evening as synoptic scale subsidence and surface high pressure pushes through the area. Upper level jet exit region spreads into the northern Great Lakes late tonight opening the door to midlevel warm advection. Favorable synoptic lift in combination with embedded shortwave energy will support a Clipper/area of surface low pressure tracking from the Straits at 12Z Fri to Toronto by 18Z. Warm midlevel air mass, 900mb temperatures of +12-13C, pushes across southern portions of the area supports an all rain forecast. Dry air and subsaturation in the lowest 9.0 kft agl yields lower confidence in rainfall amounts, less than a tenth. The forecast PoPs range from 60% likelies in the Thumb to 20 percent for much of Metro Detroit.
Better support for rainfall exists across Ontario and perhaps the eastern cwa for a time between 12-18Z Friday. Highs are tricky with the surface cold front along the Irish Hills axis at 18z pushing southward through Metro Detroit during the afternoon.

The surface front is forecasted to backdoor southward clearing the region into portions of Iowa and Illinois Friday night. Big question is then what temperatures can moderate to on Saturday especially with expected cloud cover. Latest guidance was a little cooler for Saturday highs; but additional downward adjustments are likely needed especially locations adjacent to the Lakes.

Deep midlevel trough and change in orientation to upper level jet axis is expected to result in a frontal wave pushing through Lower Michigan Sunday. There is a converging of global model solutions for a frontal timing Sunday midday/afternoon. Very warm midlevel temperatures are again expected with 850mb temperatures of +16 or +17C. Post front precipitation may changeover to snow for a time but warm ground will likely limit much of impactful accumulation outside of the Thumb. PoPS for Sunday currently reside in the high chance, 40-55 percent range.

A large area of stable high pressure is anticipated for the beginning of the next work week. Cold nighttime temperatures are expected to warm into the 40s with full sunshine.

MARINE...

A weak ridge of high pressure takes brief residence through late today as a frontal boundary washes out overhead. Northwest wind becomes light this evening before organizing out of the southeast early Friday morning in response to a clipper system, reaching a peak around 15 to 20 kt. This system tracks across northern Lake Huron Friday morning, bringing a quick round of rain and snow overnight into the first half of Friday. Winds shift to north and northwest in its wake at around 10 to 15 kt, then weaken into Saturday as high pressure builds back in. A strong cold front sinks across the region on Sunday with gusty northeast wind of 20 to 30 kt developing behind it. Probability for gales remains low, but Small Craft Advisories will likely be needed across southern Lake Huron due to wave heights around or above 4 feet. Expansive high pressure builds in behind the front on Monday, then the next cold front is expected on Tuesday.

PREV DISCUSSION...
Issued at 213 PM EDT Thu Mar 19 2026

DTX WATCHES/WARNINGS/ADVISORIES
MI...None.
Lake Huron...None.
Lake St Clair...None.
Michigan waters of Lake Erie...None.