textproduct: Detroit/Pontiac

KEY MESSAGES

- Mild conditions continue tomorrow with drizzle and light rain likely.

- Temperatures return to normal values to end the week. Additional rain showers likely late Thursday into Friday morning.

DTW THRESHOLD PROBABILITIES

* High for ceiling 5000 ft or less late tonight and Wednesday.

PREV DISCUSSION

Issued at 330 PM EST Tue Nov 3 2026

DISCUSSION...

Anomalously warm air mass with 850 mb temperatures around 12C holds over the Great Lakes, and coupled with clear skies, have allowed temperatures to push towards or into record values. Upstream, water vapor imagery highlights a strong mid-level wave progressing over northern Missouri stacked over a low pressure system situated across the central Plains. The adjacent strong low-level jet within the open Gulf setup has allowed for efficient moisture transport to take place through the central CONUS and into the northern Great Lakes. As low pressure progresses north and occludes, this will pivot the jet structure and subsequent moisture across southern Michigan, bringing rain showers starting tomorrow morning. Initial wave of precipitation will be tied to the forcing along the nose of the jet within the concurrent flow of Gulf moisture which will briefly push PW values to around 1.40", around 99.5th percentile for this time of year. An elevated jet under enhanced theta-e will promote the continuation of drizzle or rain showers through the day before a more loosely organized line of showers moves through in the late evening along a cold front.

Drizzle or spotty coverage will wane in the wake of the cold front as boundary layer heights increase and work to scour out some of the low level moisture as a dry slot moves overhead. Wrap around moisture coupled with weaker moisture advection and diurnal heating will bring return rain chances Thursday, most favorable north of the Metro region with increasing probabilities closer to the Tri- Cities and Thumb. Rain chances to then expand across all of SE MI through Friday morning along a secondary cold front. Strong thermal advection will accompany the moisture tomorrow, supporting another round of well above normal temperatures despite rain and copious cloud cover. The passage of the cold fronts will see a major pattern shift relative to the past several weeks as temperatures return to normal values by Friday and into the weekend. Highs in the 50s and lows in the 30s are expected along with breezy conditions with gusts around 25 to 30 mph. Weak signal for any precipitation chances into early next week as temperatures expected to stay around normal values.

MARINE...

Low pressure deepens over the western Great Lakes through tonight before occluding on Wednesday, maintaining moderate south to southeast wind across the area. The inbound warm air maintains a degree of low-level stability over the lakes that will limit the higher magnitude wind from mixing down. However, gusts to 20 kt will be common through tonight, with a slight uptick expected on Wednesday. Gusts as high as 25 to 30 kt are expected over the open waters of Lake Huron Wednesday afternoon and evening while shorter fetch will limit gusts to the 20 to 25 kt range over the nearshore waters. A Small Craft Advisory has been issued for the Thumb shoreline where wave heights are forecast to build over 4 feet. Saginaw Bay, Lake St. Clair, and western Lake Erie may see a brief period of gusts in excess of 25 kt during this period, but confidence is too low for an advisory at this time. A cold front brings high coverage of light showers across the area late in the day and into Wednesday night with wind veering to southwest behind the front. The weakening low pressure slowly meanders across the western Great Lakes on Thursday while deeper mixing brings gusts to 25 or 30 kt across Saginaw Bay. A stronger cold front then tracks southward across the region on Friday. This brings gusty north and northeast winds that shift northwest and weaken by Saturday. Additional light rain will accompany this frontal passage.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...Small Craft Advisory from 10 AM Wednesday to midnight EST Wednesday night for LHZ441>443.

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