Marine Weather and Tide Forecast for Grosse Pointe Park, MI

DISCUSSION

Yesterday's high temperatures remained in the 50s, despite the 00z DTX sounding indicating mixing depths all the way up to 738 mb. A strong shortwave/cold pool (-32 C at 500 mb) is exiting east of the Central Great Lakes early this morning. Subsidence will allow for a modification of the airmass over southern Lower Michigan, and highs should have no problem climbing back into the lower 60s as low-level winds become southwesterly. A series of more subtle shortwaves tracking through the western Great Lakes this afternoon and tonight will bring a very low chance of showers, mainly toward the southern Michigan border where there is better low-level moisture and proximity to the 850 mb Theta-e gradient over the Ohio Valley.

Widespread higher chances of showers arrive Saturday as a notable cold front is on track to move through during peak heating of the day. With 1000-850 mb CAPE around 500 J/kg and fairly steep mid- level lapse rates, isolated thunderstorms producing small hail appear likely.

Deep cyclonic flow then develops for the second half of the weekend into early next week, with 850 mb temps progged to bottom out in the -2 to -4 C range Monday morning. Min temps likely drop into the 30s Sunday night and Monday night; however, uncertainty remains regarding whether persistent cloud cover will prevent widespread frost/freeze conditions.

MARINE

High pressure at the surface will result in a weak pressure gradient and thus light winds, generally less than 15 knots, through Friday.
Mid levels remain active though with broad troughing over the region directing a series of weak systems aloft across the area. The next system will track through the Ohio Valley Friday evening into the overnight which will bring a period of showers to Lake Erie but winds will remain light. A stronger system is still forecast to track through the northern Great Lakes Saturday which will pull a cold front across the region Saturday afternoon bringing increased winds up to around 25 knots and thunderstorm chances.

PREV DISCUSSION
Issued at 1156 PM EDT Thu May 7 2026

AVIATION...

Clearing conditions during the early morning period as a drier and more stable environment takes hold behind a departing upper level wave. A period of clear skies will then prevail into early afternoon Friday as weak surface ridging moves through. Another weak wave traversing the Ohio valley will bring additional thicker high based cloud for the mid afternoon to evening hours. Winds prevailing from the west-southwest through the day.

D21/DTW Convection...No thunderstorms expected through the TAF period.

DTW THRESHOLD PROBABILITIES...

* None.



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