textproduct: Detroit/Pontiac

KEY MESSAGES

- Drier with weak winds Tuesday and Wednesday as highs lift into the mid to upper 80s.

- The next chance for showers and thunderstorms arrives late Wednesday into Thursday with temperatures still above normal.

- Unsettled weather is possible into Friday with a return to near- normal readings.

DISCUSSION

Stalled low pressure near the western shores of Lake Erie continues to produce a decaying swath of deformation-driven rainfall across some downriver communities, but latest radar trends show it quickly dissipating. The low is progged to track southeastward this evening and overnight as high pressure from the upper Midwest builds into Lower Michigan. Near-normal temperatures tonight with lows in the upper 50s to lower 60s, perhaps slightly lower near the Tri-Cities where skies will be clear longer and dewpoints will be notably lower.

Shortwave ridging overhead promotes column subsidence and dry weather on Tuesday. 850 mb temperatures should range from 15C to 17C, leading to highs in the mid 80s for most locations beneath a patchy diurnal cumulus field. A very low chance exists for pockets of vertical development, leading to a few brief and isolated raindrops, although forecast soundings indicate minimal CAPE. The surface high pressure influence will limit the sharpness of the pressure gradient, resulting in weak winds, loosely organized out of the northeast.

Slightly warmer Wednesday with fewer clouds and highs above normal, in the upper 80s. The geopotential height field will eventually succumb to gradual mid level height falls throughout the day as a low amplitude trough transits the northern periphery of a Four Corners ridge. This wave will phase with northern stream energy, slowing as it digs across Lower Michigan. Dry weather should remain intact Wednesday as the upstream cold front turns stationary.

Showers and thunderstorms become more widespread throughout the day on Thursday as the front draped over Wisconsin slowly advances across southern Lower Michigan. Gulf moisture return will be underway amidst a weakening anticyclonic southwesterly low-level jet. Mid level lapse rates (700-500 mb) struggle to break above 6.5 C/km limiting UVVs while 0-6 km bulk shear will be marginally conducive to some organized potential at 20-25 knots. As of now, the severe threat appears low/isolated, but a sharp rise in PWATs poses a minor heavy rain and wind threat. The front will be slow to work southeastward; therefore, highs should hold above normal once again. Could be slow to dry out on Friday before a speed max tracks across I-80 and into the Ohio Valley with more convective potential.

MARINE

High pressure to hold across the Great Lakes today and tomorrow which will support lighter winds across the region. Some localized stronger winds speeds will be found across the Saginaw Bay through tonight given the more favorable northeast fetch with isolated gusts up to 20 knots. High pressure will wash out across the Appalachia region during the midweek period but the overall pressure gradient will remain weak over the Great Lakes, supporting the continuation of lighter winds. A low pressure system and cold front will move through Thursday into Friday, bringing the next chance for active weather.

PREV DISCUSSION

Issued at 1227 PM EDT Mon Jul 6 2026

AVIATION...

Drier low level air (as seen in the clear skies and surface dew pts falling into the 50s along/north of M-59) will continue to advance south through the afternoon. Clear to mostly clear will prevail by early evening and persist through most of the night. However, with persistent northeast flow, some low level moisture will attempt to move back in from the east late tonight. KDET stands the best chance of seeing an MVFR cloud deck developing and persisting much of Tuesday, with chances diminish as one heads northwest. It seems reasonable that DTW-YIP-PTK wilL have a period of MVFR clouds as well, but left FNT/MBS ceiling free for now.

D21/DTW Convection...No thunderstorms expected in the taf period.

DTW THRESHOLD PROBABILITIES... * Low in ceilings aob 5000 feet this afternoon, medium by sunrise Monday and continuing during the day.

DTX WATCHES/WARNINGS/ADVISORIES

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