textproduct: Detroit/Pontiac

KEY MESSAGES

- Another round of rain showers with possible embedded thunderstorms develops mainly after midnight tonight lasting through tomorrow morning.

- Dry weather and cooler but still near normal temperatures tomorrow afternoon and Saturday.

- Warmer temperatures moving in Sunday into mid-week come with an active shower and thunderstorm pattern.

DTW THRESHOLD PROBABILITIES

* Medium for ceilings at or below 5000 ft tonight. High Friday.

* Low for thunderstorms this evening. Low for thunderstorms Friday.

PREV DISCUSSION

Issued at 310 PM EDT Thu Apr 9 2026

DISCUSSION...

Cold front continues its progression through southeast Michigan this afternoon as shower coverage gradually wanes across the south. The cold front is expected to stall out around the southern Michigan by the end of the end of this afternoon. High pressure settling in behind the front brings clear skies across most of southeast Michigan. Gusty afternoon winds from better mixing will decrease into this evening as lower level flow weakens and the boundary layer becomes more stable. Low end PoPs(20-30%) and lingering clouds will remain in the forecast early in the evening along the southern boundary supported by weak ascent downstream of a mid level wave.

Tonight will see increasing coverage of showers, mainly after midnight, as the mid level wave moves along this front drawing it northward and nocturnal low level jet ramps up. Weak mid level lapse rates and the lack of surface instability will limit the thunder potential, but a few elevated embedded thunderstorms will be possible. PWATs increasing towards and inch and potentially reaching one inch along a narrow corridor arriving with the low-mid level thetae. A SW to NE axis of rainfall averaging 0.50 to 0.75 inches is forecast through tomorrow morning, which will be focused across central to northern portions of the CWA. Any embedded thunderstorm activity may be able to push localized amounts up towards one inch of rainfall. Rainfall rates should be held in check for the most part given the lack of strong instability.

High pressure will build back into the region late Friday bringing an end to the precipitation chances, but lower level moisture trapped under an inversion will keep higher coverage of clouds into Friday night. High pressure center moves directly over Michigan Saturday morning with increasing subsidence bringing a cloud clearing trend. Temperatures settle down into the mid 50s for highs during the afternoon to start the weekend under the mostly clear skies.

Sunday will see strong warm/moist advection driving by a low pressure system that will track across the northern Plains clipping the northern Great Lakes over Lake Superior. Temperatures at 850mb will surge to 10+C offering well above normal temperatures Sunday afternoon in the 60s to low 70s. Better moisture will also result in increasing rain and thunderstorm chances Saturday night/early Sunday morning along an advancing warm front. The trajectory of this system will carry rain chances Sunday evening into Monday. Pattern remains active through the early half of the week with relatively high confidence in above normal temperatures in the 70s at least through Tuesday. Models depicting weaker embedded shortwaves early week with the greater western CONUS trough ejecting into the plains toward mid- week will be responsible for multiple rounds of rain and thunderstorm chances during this period. Mid-week period currently holds the better organized convective potential, but will have to see how the pattern shakes out with how the ridge across the Eastern CONUS may affect the inbound Pacific trough. This would direct greater convective potential to the west.

MARINE...

Southerly flow gradually decreases this morning and veers toward the west throughout the day, behind an Ontario low pressure system and its associated cold front. Strong low level flow tied to the passing low also departs which ensues peak morning gusts stay below gales, particularly for central Lake Huron where there was prior concern. The wave response becomes less prominent as the day continues, but still exceed Small Craft Advisory criteria for the southern Huron nearshore zones, therefore an advisory remains in effect. Rounds of showers decrease from northwest to southeast today, with low potential for thunder. A wave lifting out of The Plains leads to additional opportunities for showers and perhaps a thunderstorm tonight and Friday, while some light snowfall is more likely for the north/central Huron basin. High pressure then builds out of the Upper Midwest to start the weekend with drier and weaker northwest flow. Active weather will be possible again Sunday through Tuesday due to several passing disturbances. Potential exists for gusts to gales, mainly late Sunday into Monday.

HYDROLOGY...

Another round of showers develops mainly after midnight tonight that lasts through tomorrow morning before ending tomorrow afternoon. This system brings a SW-NE rainfall axis with amounts focused mostly across central and northern portions of southeast Michigan. Rainfall totals average 0.50 to 0.75 inches in a 6 to 12 hour time window. There is a chance for localized totals near 1 inch where embedded thunderstorms may develop. Flooding potential remains low with this event, although the new rainfall could slightly delay drainage from river and stream systems after the heavy rain that occurred last weekend.

DTX WATCHES/WARNINGS/ADVISORIES

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