textproduct: Detroit/Pontiac

KEY MESSAGES

- Stretch of warm conditions throughout the work week with daytime temperatures in the 70s each day for most locations.

- There is a Slight Risk for severe thunderstorms Tuesday night, mainly between 8 pm and 2 am. Storms will be capable of producing wind gusts to 60 mph, large hail and isolated tornadoes.

- There is a Marginal Risk for severe thunderstorms Wednesday and still another round of storms possible Thursday.

- Each episode of storms brings the possibility for locally heavy rainfall.

DTW THRESHOLD PROBABILITIES

* Medium for ceilings aob 5000 feet today, high tonight.

* Low for thunderstorms today, then becoming medium late this evening and tonight.

PREV DISCUSSION

Issued at 306 AM EDT Tue Apr 14 2026

DISCUSSION...

The well advertised, several day long, active stretch of weather is underway. The warm front has become established across northern MI with the broad surface low back over Iowa. The most recent mid level wave ejecting from the longwave trough over the western conus pairing with a strong low level jet has resulted in an expansive line of convection spanning from northern MI back into southern MN early this morning. The best instability and shear remain to the west but as the jet strengthens and pushes east, it will bring increasing levels of shear and instability into southern MI. Forecast starts with Severe Thunderstorm Watch #107 across Mid MI to account for the current upstream activity tracking through the region overnight. This will mostly be for a hail and wind threat.

Last of the overnight convection should be east of the area for the most part by 12Z this morning leaving us in a bit of a lull through the early part of the day. Many of the hires models still show hints of precip along the warm front at times this afternoon which wouldn't be out of the question with the strength of warm air advection and wealth of instability (2k J/kg) present, but we'll lack stronger upper level forcing until later this afternoon and evening when the next mid level shortwave and convectively driven surface low ripple along the front through southern MI. SPC continues to have the whole area in a Slight Risk of severe storms which looks to target the 00-06Z window this evening into tonight. With similar overall setup, forcing, low level jet, moisture quality, CAPE, 40 knots of shear, and steep mid level lapse rates, etc to what is going on in the Midwest and Great Lakes tonight, see no reason this risk should change moving forward. Risks will be large hail, damaging winds, and isolated tornadoes. Even after the initial convective cluster rolls through, the upper level trough will drift over the Midwest by late Tuesday night which will steer additional mid level energy across the area with the stall front still draped across Mid MI. This keeps southern MI in a Marginal Risk for additional severe weather on Wednesday.

Additionally, a growing threat will be for possible flooding. With PWATs up around 1.25 inches or more through the period, and surface dewpoints in the 60s, there will be ample moisture for these storms to use. QPF during the period of time from Tuesday night through Wednesday night is around 1.5 inches across the whole CWA. With the potential for convection training over the same locations, some local probabilistic guidance shows the potential for 2 to 4 inches of rainfall during this time. This combined with previous ground soaking rain over the last week and several rivers already running high could lead to flooding concerns. WPC has a portion of the area in a Slight Risk on Tuesday and Marginal Risk on Wednesday.

Upper level trough will cross the area on Thursday providing yet another chance for storms. Mild conditions continue on Friday but we should get a break from precip with increasing heights aloft and surface ridging sliding through. This looks to be a short lived break though as the next deep trough is already working east across the Plains which will be additional precip chances through the weekend.

MARINE...

Showers and thunderstorms exit east this morning in favor of drier weather by afternoon. Southwest flow reemerges across the south with a gradual veering trend in wind direction to the north as a warm front settles near Saginaw Bay. This front will be the focus for another round of showers and thunderstorms to develop late this evening and overnight. Some of these storms may be strong to severe, capable of large hail, heavy rain, and wind gusts over 34 knots. This unsettled pattern persist into the mid-week period. Wind and wave concerns will mainly be tied to thunderstorm activity.

HYDROLOGY...

An active pattern will bring periodic chances for showers and thunderstorms tonight through Thursday. Each episode brings the possibility for locally heavy rainfall, particularly where focused areas of thunderstorms develop. Rainfall amounts of half an inch to an inch will be possible for a round of rain tonight. Additional rainfall between a half and one and a half inches currently forecast to fall between Wednesday and Thursday. While widespread flooding is not expected, some minor flooding of low lying, poor drainage and urban areas along with rises on area rivers are possible.

DTX WATCHES/WARNINGS/ADVISORIES

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