textproduct: Detroit/Pontiac

KEY MESSAGES

- Moderate easterly wind continues Thursday which keeps temperatures on the cool side of average.

- High pressure settles overhead by Friday and brings dry weather and a gradual warming trend through the weekend.

DTW THRESHOLD PROBABILITIES

* Low in ceilings aob 5000 feet tonight and Thursday.

PREV DISCUSSION

Issued at 352 PM EDT Wed Sep 23 2026

DISCUSSION...

SE Mi remains between a broad area of surface high pressure centered in eastern Canada and TN valley low pressure that has a trough reaching up into central IN/OH. This is making gusty E-NE wind the weather highlight this afternoon. Cool air reinforced by gusts near 30 mph check temperatures in mid to upper 60s, further limited by the cloud shield reaching up from the Ohio valley low. This system is also grazing the border region with a stray light shower as moisture gets wrung out around the north flank of the 500 mb circulation. The low has less influence farther north toward the Tri Cities and Thumb where full daytime heating is producing generous coverage of shallow cumulus within the cool high pressure air mass augmented by Great Lakes aggregate boundary layer moisture. These clouds fade with sunset while the IN/OH circulation drifts toward the mid Appalachians tonight, just enough to pull the cloud shield south of the Mi border after midnight. Gradient wind then remains elevated enough to hold a temperature trend similar to last night for lows in the mid 40s to around 50 by sunrise Thursday.

Slow evolution of the mid level rex block proceeds during the late week period resulting in the 500 mb ridge component strengthening over the Midwest and Great Lakes. Solid agreement among the 23/12Z deterministic models shows this resulting in surface high pressure settling more over the Great Lakes as the potential nor'easter matures off the New England coast. Easterly wind diminishes slightly during the transition Thursday while maintaining an air mass of similar temperature and cloud character as today. Textbook early fall weather for SE Mi then becomes more firmly established by Friday with a gradual modification of the cool high pressure air mass through the weekend. This allows afternoon temperatures to gain ground back into the lower 70s with dry weather through Sunday.

MARINE...

A moderate pressure gradient responsible for brisk east to northeasterly flow will persist through the evening. Gusts ranging between 15 to 25 knots are expected through tonight which will help maintain more elevated wave action along the shoreline, where Small Craft Advisories remain in place. High pressure will slowly build in from Quebec and Ontario through the end of the week which will relax wind speeds, leading to a longer period of lighter winds. These light winds with mostly dry conditions are expected to last through the weekend as this high pressure system settles across the northern Great Lakes.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...Small Craft Advisory until 4 AM EDT Thursday for LEZ444.