textproduct: Detroit/Pontiac

KEY MESSAGES

- Dry weather with near-normal, pleasant temperatures for the end of the week.

- A slight chance for a shower Saturday afternoon, otherwise a quiet weekend, accompanied by slightly above-normal temperatures.

DISCUSSION

Quasi-zonal upper level flow over portions of the Pacific Northwest and southern Canada will bring low amplitude ridging to the Central Great Lakes through at least the middle portions of the weekend period. Calm winds and time of year considerations suggests some fog potential at daybreak Friday morning. Surface condensation pressure deficits point to some likelihood particularly in the Thumb down to the I69 corridor. MOS guidance also shows some signal and decided to add patchy fog to the gridded database. Temperatures will be in the upper 70s to around 80 degrees each of the next 3 days which is at or slightly above normal.

Models suggest that by late Saturday there is a slight chance for some showers across southern portions of the forecast area during peak heating. From a macro perspective, weak deformation forcing can arise out of latent heating churn that typically occurs inside of an upper level ridge. In this case there is a ribbon of potential vorticity that is resolved near the Ohio River that begins to migrate northward. Big limitation will be the residual subsidence that resides in the 2.0 to 7.0 kft agl layer that will serve as a good capping inversion.

Troughing then enters and expands through Lower Michigan Sunday pushing a cold front through the region. With post frontal mixing temperatures are not expected to cool that much for Sunday but dewpoints will be some 8 to 10 degrees lower. Chilly conditions are expected Sunday night with some 40s possible in Midland county by Monday morning. Another round of ridging is anticipated for Monday and Tuesday.

MARINE

Winds steadily weaken this evening as high pressure builds over the central Great Lakes. Said high then drifts overhead through Friday night leading to benign marine conditions to close the work week. Active pattern returns late this weekend as low pressure lifting through northern Ontario drags a cold front into the area before it looks to stall over Lake Huron.

PREV DISCUSSION

Issued at 110 PM EDT Thu Sep 10 2026

AVIATION...

High pressure to support VFR conditions through tonight. For this afternoon, few-sct cu will be possible through the early afternoon under a more expansive cirrus deck aloft. All cloud coverage decreases tonight, leading to generally clear skies and light winds. This will bring back fog chances prior to daybreak. Given the northeast flow, KFNT to KPTK will exhibit highest chances for fog, followed by KMBS. The Metro terminals retain the lowest confidence for any visibility restrictions for fog. Outside of fog chances, VFR conditions to then continue into tomorrow.

D21/DTW Convection...No thunderstorms will occur 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.