textproduct: Detroit/Pontiac

KEY MESSAGES

- Lingering showers and isolated thunderstorms tonight.

- Dry conditions prevail Monday and Tuesday, with highs mainly in the 80s.

DTW THRESHOLD PROBABILITIES

* Medium in ceilings aob 5000 feet tonight. Low Monday morning.

PREV DISCUSSION

Issued at 301 PM EDT Sun Jul 5 2026

DISCUSSION...

A compact mid level deformation axis associated with a meso scale mid level short wave feature produce widespread rain across the southern sections of the forecast area today. The highest rainfall totals (estimated at 2 to 4 inches) occurred early in the day south of the I-94 corridor where deep convection occurred. This wave continues to slowly depart to the east. Remnant mid level convergence/deformation looks to persist into the early evening, with the convergence axis now shifting farther north toward the I-69 corridor. Various high res solutions indicate some areas of showers/isolated thunderstorms to continue to affect the area through the night as Se Mi will continue to reside within deep layer moist axis and within lingering deformation on the north side of a broad 850mb low centered over Ohio. Ongoing surface based instability development has mainly been focused across the western sections of the CWA late this afternoon, with weak elevated instability persisting through the night.

Mid level ridging and sfc high pressure will expand across the western and northern Great Lakes Monday, while mid level troughing holds across the eastern Great Lakes. The resident deep layer moisture will trend southward during the course of the day while east-northeast winds gradually advect a drier and more stable airmass across Se Mi. Model soundings indicate mixing depths limited to 5k feet, which will equate to forecast highs in the low 80s considering early day cloud cover. The easterly flow will warrant a little cooler readings downwind of Lake Huron. The mid level ridge and associated surface high pressure will become centered over Lower Mi Tuesday, with the corresponding deep layer subsidence and dry air supporting a dry forecast. Full solar insolation will boost afternoon highs to low to mid 80s.

The mid to late week pattern will feature a zonal flow across the northern tier of the US with the next feature of interest being a progressive short wave and associated frontal boundary. NBM places the best chance for convective with this feature on Thursday, although the spectrum of ensemble members suggest a timing anywhere from Thursday into Friday. The thermal region through the end of the week supports temps near to slightly above normal readings through the end of the week (highs mainly in the 80s).

MARINE...

Rain showers and a low chance for a thunderstorm will continue across the southern Great Lakes as a humid airmass continues to reside across the Great Lakes. High pressure will build in tomorrow and Tuesday which will greatly mitigate rain chances and will maintain light winds. The exception will be through the Saginaw Bay, as the favorable northeast flow brings localized stronger winds with gusts 20 to 25 knots. Small Craft Advisories remain in effect across the Saginaw Bay today but will drop tonight as gusts diminish aob 20 knots. Winds are expected to peak back around 20 to 22 knots tomorrow, but will remain just shy of Small Craft Advisory thresholds.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...Small Craft Advisory until 10 PM EDT this evening for LHZ421-422.

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