textproduct: Detroit/Pontiac

KEY MESSAGES

- Dry conditions with temperatures dipping below average during the mid to late week period.

- Next chance at precipitation Saturday night into Sunday.

DTW THRESHOLD PROBABILITIES

* Low for ceiling 5000 ft or less this afternoon and evening.

PREV DISCUSSION

Issued at 323 AM EDT Wed Jul 22 2026

DISCUSSION...

Deep H3 to H5(sub 560dam) troughing is in place across all of the Great Lakes this morning with surface extension of cold front now pushing southward through portions of central IN/OH. Much cooler conditions in this setup as 850mb temperatures currently range between +4C to +6C areawide. Surface dewpoints have easily dropped into the 40s for many areas and temperatures at daybreak are expected to be in the lower 50s. Projected absolute vorticity charts support another vorticity maximum, collocated with composite trough axis, digging into the Lake Huron between 18-00z today. Northerly gradient with legitimate cold pool aloft over Ontario results in fresh isentropic downglide and cold advection over the area today. Gusty well mixed northwest surface winds of 10 to 25 mph today. Forecast soundings support high static stability in the 6.0 to 16.0 kft agl yielding dry conditions but with some boundary layer cumulus this afternoon.

Flow trajectories rapidly evolve to anticylonic tonight as strong surface high pressure builds into Wisconsin. Main narrative tonight is very chill nightitme temperatures with the potential for some areas outside of the Detroit urban heat island to dip into the 40s. Moderating and warming airmass between 4.0 and 8.0 kft agl will dry out any lingering low-mid relative humidity for the daytime Thursday. Very comfortable weather will exist Thu with temperatures in the upper 70s and dewpoints in the lower 50s. Progressively warmer Friday and Sunday with incremental increases in surface humidity. Latest indications are surface ridge axis will continue to hold through Southeast Michigan.

Jet exit region with anticyclonically wave break pushes into Lower Michigan for Sunday. Models suggest shortwave energy cascading in vicinity of the Southeast Michigan with return of warm advection. Persistent northwest flow could lead to a more active period early next week with regards to precipitation. Current forecasts suggest highs in the 80s early next week.

MARINE...

High pressure moves into the area after our cold front has fully passed the Great Lakes region, resulting in some dry weather, and strong cold air advection that will encompass the area for the next couple of days. Winds will be relatively gusty and coming out of the northwest through today then subsiding on Thursday. Small Craft Advisories remain in effect for near shore areas of Lake Huron around the thumb and Saginaw Bay. Beach Hazard Statements are in effect around the thumb throughout today as well. Calmer conditions continue for the rest of the week.

DTX WATCHES/WARNINGS/ADVISORIES

MI...Beach Hazards Statement through this evening for MIZ049.

Lake Huron...Small Craft Advisory until 10 PM EDT this evening for LHZ421- 441>443.

Small Craft Advisory until 4 PM EDT this afternoon for LHZ422.

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