textproduct: Detroit/Pontiac

KEY MESSAGES

- Dry conditions with warmer temperatures Monday.

- Chance of showers and thunderstorms starting Monday night. Greater potential exists Tuesday, with locally heavy rainfall possible.

- Hot and humid Wednesday and Thursday along with additional thunderstorm chances.

DISCUSSION

Dry and stable conditions exist to finish the weekend period, as high magnitude upper level ridging maintains control atop surface high pressure anchored over Ontario. Little variation in the resident profile expected over the next 24 hours. Deep column subsidence held within this environment affords limited cloud production, while a resident dewpoint of mid 50s to lower 60s represents the lowest expected humidity over the upcoming week. Lows tonight in the 50s, with highs pushing well into 80s Monday as mean thickness readings peak as the upper ridge apex slips eastward.

Higher amplitude upper level trough digging into the upper midwest will effectively shunt a lower amplitude positively tilted disturbance currently drifting across the plains northeast toward the great lakes by early Tuesday. Strengthening low level jet Monday night along the lead edge of the height falls will initiate a pronounced period of moisture transport during this time. Surface dewpoint projected to surge sharply into the mid 60s to lower 70s, with model PWAT values approaching 2 inches by Tue evening. Supportive large scale ascent tied to the passing wave timed coincident with daytime heating will yield a high probability for some clusters of showers and thunderstorms to develop. Profile characterized by high quality moisture at the deep level and associated weak instability, but lacking in meaningful low level or deep layer shear. This suggests limited potential for greater convective organization, although isolated stronger downbursts could materialize driven by localized precipitation loading. Heightened risk for heavy rainfall exists given expected slow storm motion and prospective efficient rainfall rate. WPC maintains a Marginal Risk for excessive rainfall across lower Michigan.

In the wake of Tuesday's system, southwest flow strengthens across a deep layer within the backdrop of building upper heights. Strong low level warm air advection takes hold on Wednesday as 850mb temperatures climb to near 20C. This sets the stage for an extended stretch of high magnitude warmth and humidity for the late week period, as surface temperatures climb into the upper 80s to lower 90s both Wednesday and Thursday. This occurs while dewpoints remain locked in the upper 60s to lower 70s. This translates into peak heat index values solidly in the 90s both days. While larger scale capping concerns will exist, some convective potential will exist with reliance on upstream convective behavior. This convective potential does introduce minor predictability barriers regarding exactly how high max temperatures will peak each day.

MARINE

Western periphery of a high pressure system will hold across the Great Lakes today through tomorrow afternoon. This will maintain dry conditions along with light winds. Winds from the north to northeast will back to the east-southeast through tomorrow in response to the departure of high pressure. Weak low pressure will then bring some unsettled weather through the midweek period. Some periodic rain showers with embedded rain showers will be likely on Tuesday, with lower end potential Wednesday onwards. The weaker pressure gradient keeps wind gust potential aob 20 knots outside of any thunderstorm activity.

PREV DISCUSSION

Issued at 1256 PM EDT Sun Jun 7 2026

AVIATION...

Very dry airmass in place will continue to support clear to mostly clear skies through tonight as high pressure is slow to exit the Central Great Lakes. There was limited low level stratus this morning that came off Saginaw Bay/Lake Huron, which has transitioned to modest (FEW-SCT) VFR CU field early this afternoon, but is mixing out as we speak. Winds remain light easterly into tomorrow, thus another low chance for low stratus to develop around MBS late tonight into early Monday. D21/DTW Convection...No thunderstorms expected through the TAF period.

DTW THRESHOLD PROBABILITIES...

* Low for cigs aob 5000 feet tomorrow afternoon.

DTX WATCHES/WARNINGS/ADVISORIES

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