textproduct: Detroit/Pontiac

KEY MESSAGES

- Seasonable temperatures today into Saturday with prevailing dry weather apart from a slight chance for a brief shower this afternoon or evening.

- A warming trend sends temperatures above normal early next week with increasing chances for showers and storms.

DTW THRESHOLD PROBABILITIES

* Low for ceilings aob 5000 feet.

PREV DISCUSSION

Issued at 342 AM EDT Thu Aug 27 2026

DISCUSSION...

A longwave trough is situated over the Great Lakes this morning with an embedded midlevel shortwave exiting toward Lake Ontario. At the surface, the cold front that passed through last night is now midway across Lake Erie. Thermal change behind this front is relatively weak, and guidance supports another seasonable day with highs near 80. Diurnal instability will be stifled by mid-level warming via post-wave subsidence, but enough low-level moisture will exist for a healthy flare-up of cumulus. A few shallow late afternoon and evening showers will also be possible, mainly over the Thumb where veering northerly flow off the lake provides some convergence to act as a trigger.

A backdoor cold front marking a much drier air mass will arrive this evening and precede high pressure that settles in on Friday. Light northerly wind allows dew points to settle into the 50s, offering very pleasant and less humid conditions that continue into Saturday. By Saturday afternoon, a slight southwest breeze develops as the surface ridge settles east. A weak disturbance working into the region later in the day leads to fgen and some convection near a developing warm front, but this is favored to set up over northern MI so have maintained a dry forecast.

A warming trend remains on track for early next week as a subtropical ridge migrates from the Four Corners into the southern Plains and eventually the Tennessee Valley. Thickness advection commences Sunday, pushing temps above average, then strengthening southwest flow north of the ridge advects 850mb temps around 20C or above for Monday and Tuesday. NBM and LREF ensemble guidance continue to advertise 25-50% probability for highs in excess of 90 degrees each day, with highest likelihood over the urban corridor. The caveat for the heat forecast will be potential for periodic MCS activity as several ridge-running shortwaves are shown in mid-level flow during this period. A cold front on Tuesday or Wednesday looks to break the heat and may bring a more focused signal for convection.

MARINE...

Post-frontal northwest winds in place today with peak gusts of 20- 25kts over the northern half of Lake Huron. Winds gradually weaken this evening as high pressure becomes established over the central Great Lakes. Said high then drifts overhead Friday into early Saturday maintaining lighter winds and quiet weather.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None.