textproduct: Detroit/Pontiac

KEY MESSAGES

- Dry and warm today and tomorrow.

- Showers with a chance of thunderstorms tomorrow night and Wednesday.

DTW THRESHOLD PROBABILITIES

* None.

PREV DISCUSSION

Issued at 345 PM EDT Mon Sep 7 2026

DISCUSSION...

High pressure and inbound ridge axis will control the weather today into tomorrow. Surface high pressure expected to slide to the eastern Great Lakes tonight while ridge axis ridge axis begins to slide into the central Great Lakes. The general southeast flow today is helping support a healthy cumulus field across most of southeast Michigan. Lack of deeper moisture and stability will keep the forecast free of precipitation through the remainder of today and through tonight. Lows tonight down into the 50s tonight. The increasingly south to southwest flow tomorrow with the ridge axis and eventually passage of it will lead. This will result in warm/moist advection that will allow daytime highs on Tuesday to reach the low 80s and surface dewpoints to climb above 60 degrees.

Helping drive this warm/moist airmass into the region will be a Pacific trough that is forecast to eject across the northern plains and central Canada. Low-mid level jet forcing along with the systems associated cold front will lead to the next chance of widespread rain and scattered thunderstorms Tuesday night through Wednesday. Within the theta-e ridge will be a plume of deep moisture that has PWAT values to around 2 inches and be the corridor of focused convection. The southwest to northeast orientation of this corridor will lead to PoPs increasing across the Saginaw Valley first on Tuesday night before greater upscale growth occurs through Wednesday morning as the system propagates downstream into southeast Michigan over the course of Wednesday. Less favorable early day timing and the potential for cloud cover may temper a stronger instability response. Towards the southern Michigan border would be the favored locations that greater instability may be able to develop. While shear will be favorable, mid-level lapse rates do not appear to be very steep. At this time, the severe threat appears limited and held south of the state with general thunderstorms more likely across southeast Michigan. Given the degree of moisture though, locally heavy rainfall will certainly be possible. Current QPF guidance is to around a half inch across the Saginaw Valley with lesser amounts with southeast extent. In addition, winds will be elevated on Wednesday with increasing pressure gradient and gusts of 25 to 30 mph will be possible.

A trailing trough will help push the cold front out of the area by Thursday morning. Post frontal airmass will bring cooler and less humid conditions for Thursday and Friday. Temperatures back into the 70s and dewpoints down in the 50s. Over the weekend, temperatures look to rebound back to around 80 degrees within quasi zonal flow. Passing shortwaves to the north offer low end PoPs at this stage.

MARINE...

High pressure drifts over the region through Tuesday maintaining benign marine conditions. South turning southwesterly winds strengthen Tuesday night into Wednesday as seasonably strong low pressure system tracks across southern Canada into Hudson Bay. While a gust or two two could reach entry-level gales over central Lake Huron, winds are expected to peak around 30kts. Return of a humid airmass back to the region will support shower and thunderstorm chances for much of the day Wednesday before the attendant cold front crosses late evening. Moderate northwesterly flow follows for Thursday however only a glancing shot of cold advection and a rapidly diminishing gradient has high pressure builds caps winds aob 30kts.

DTX WATCHES/WARNINGS/ADVISORIES

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