textproduct: Detroit/Pontiac

KEY MESSAGES

- High pressure establishes pleasant weather today through Tuesday with warm days (80s) and cool nights (50s).

- The next chance of showers and thunderstorms arrives late Wednesday. Better coverage is expected Thursday.

- Mainly dry weather is expected to start the weekend.

DTW THRESHOLD PROBABILITIES

* None

PREV DISCUSSION

Issued at 350 AM EDT Mon Aug 3 2026

DISCUSSION...

High pressure brings pleasant weather to SE Mi during the early week period. It ensures dry conditions and seasonable temperatures with lower humidity today and Tuesday. For today, the surface ridge axis is positioned to our west which maintains a light but steady northerly low level wind field. Low level dry air advection drops surface Td comfortably down into the mid 50s across the region. Full sun and maximum daytime surface heating build a deep boundary layer in model soundings that is way too dry for any cumulus during the afternoon. Guidance highs in the lower 80s are right at normal values for early August. Onshore flow into the Thumb shoreline keeps readings a few degrees cooler.

High pressure slides steadily across Lower Mi tonight and early Tuesday becoming centered over PA/NY by afternoon. This results in light SW wind into Lower Mi which combines with the mid/upper level ridge overhead to lift temperatures a few more degrees both Tuesday and Wednesday. Guidance highs in the mid 80s look reasonable each day while there is a greater mid/high cloud component and an uptick in humidity by Wednesday afternoon.

Wednesday's cloud and humidity increases are driven by continued SW flow between Atlantic coast high pressure and the next low pressure and frontal system moving in from the Plains/Midwest. There are still some timing differences among the 00Z deterministic models regarding the position of the surface low/front Wednesday and Wednesday night. Considering the mid/upper level trough spends much of the day digging southward into the Plains states, prefer model solutions offering slower eastward frontal progress until Wednesday night and Thursday for SE Mi. It then looks like a slow frontal passage through the area Thursday into Friday as the mid/upper level long wave trough hangs to our west while guiding a new short wave system from the Plains into the Great Lakes. If this feature does materialize, then it would help nudge the front through Lower Mi into Ontario/Ohio where it dissipates to begin the weekend.

MARINE...

High pressure influence builds into the region today offering drier weather and weaker winds. Light flow flips southerly on Tuesday as the center of high pressure slides across Lake Erie. A slow moving frontal boundary will drift in from the west mid-week leading to future opportunities for showers and thunderstorms. No significant pressure gradient constriction is forecast, therefore headline-free conditions should persist through the end of the week.

DTX WATCHES/WARNINGS/ADVISORIES

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