textproduct: Detroit/Pontiac

KEY MESSAGES

- Showers increase coverage across the area tonight leading to an active pattern that continues Friday and Friday night.

- Temperatures return to a more typical range for early November but are much cooler than recent days.

- Dry weather helps temperatures rise a few degrees above normal again during the weekend and early next week.

DTW THRESHOLD PROBABILITIES

* High for ceiling 5000 ft or less tonight and Friday.

PREV DISCUSSION

Issued at 347 PM EST Thu Nov 5 2026

DISCUSSION...

A cooling trend is on schedule to bring temperatures back down to a more typical range for early November during the late week. The change is brought by low pressure and associated cold fronts spanning the area from Quebec, across the Great Lakes, and into the Midwest. Smaller scale circulations within the long wave mid/upper level trough are also regulating greater coverage of showers toward the Tri Cities and northern Thumb this afternoon. The pattern of showers then shifts southward tonight along and ahead of the cold front as it sweeps through SE Mi. Low temperatures are projected to drop down into the mid 30s north, but after rain ends late tonight. Lows hold up around 40 south of I-69 and across metro Detroit to ensure no precipitation type concerns, although freezing level drops down close to 1000 ft in model soundings through Friday morning.

An impressive round of mid to upper level height falls is shown in satellite imagery this afternoon and model data tonight diving from northern Ontario into the central Great Lakes. This is the primary driver of the frontal passage tonight before the system closes off overhead during Friday. Scattered to numerous coverage of showers is maintained by the strong 500 mb cyclonic circulation and cold core, especially during the afternoon as surface temperatures strain toward 50, and as the low moves slowly across southern Lower Mi. Temperatures at 500 mb hover around -22 C, about normal for this time of year, but with the added boost from strong forcing and daytime instability. Shower coverage and intensity then pick up considerably Friday night as the low shifts eastward and the mid level trowal/deformation wraps in from the northern Great Lakes. Increased model QPF reflects the 850-700 mb theta-e advection, strong dynamics, and also a boost of enhancement from Lake Huron before the moisture axis slides eastward Saturday morning.

The 05/12Z models show a faster than expected eastward progression of the low pressure system considering its closed/amplified character. The Friday Great Lakes system reaches upstate NY during Saturday leaving Lower Mi dry with temperatures rising back a few degrees above normal by Sunday. Midwest surface high pressure builds into the Great Lakes as the northern stream westerlies shift back north into Canada. The resulting farther north low pressure track takes the edge off the next cold front expected during the Sunday night/Monday timeframe. Guidance forecast temperatures around 60 look reasonable given this larger scale pattern holds through the middle of next week.

MARINE...

Trough of low pressure remains stretched from Quebec southwestward through the central Great Lakes today. An upper low will drift south today causing the surface trough to close into a low over Lake Huron Friday before the whole system drifts off to the east for the weekend. The trough will pull a cold front through the area later this evening before the it wraps back up into a low. Gusty southwest winds today will flip around to the northwest Friday into Saturday with more northerly winds across Lake Huron. The cold air advection is helping to increase mixing depths over the water will help keep the winds speeds and waves elevated through this time. This will all lead to an extended period of Small Craft Advisories across much of the waters now through Saturday morning.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...Small Craft Advisory until 10 AM EST Saturday for LHZ421-422.

Small Craft Advisory until 10 AM EST Saturday for LHZ441.

Small Craft Advisory from 9 AM Friday to 10 AM EST Saturday for LHZ442-443.

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