


Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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193 FXUS63 KDTX 122342 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 742 PM EDT Sat Jul 12 2025 .KEY MESSAGES... - Temperatures in the mid 80s tomorrow, upper 80s Monday, then reaching around 90 degrees on Tuesday. - Dry start to the week, but showers and thunderstorms likely return Wednesday-Thursday. && .AVIATION... Isolated showers and thunderstorms have developed along a boundary this evening, but activity looks like it will avoid all terminals as activity pushes east throughout the evening. A cold front currently tracking across Lake Michigan will then work through tonight possibly touching off a few showers. Main outcome of this front will be a SCT low VFR/MVFR deck tonight before skies improve tomorrow. Gusty winds this afternoon have decreased at press time to around 10 knots or less. Winds turn westerly tonight with the frontal passage and remain mostly below 10 knots. For DTW/D21 Convection...Thunderstorm chances this evening have come to an end and any thunderstorms chances tomorrow look very limited tomorrow. THRESHOLD PROBABILITIES... * Moderate for ceiling 5000 ft or less with the cold front late tonight. && .PREV DISCUSSION... Issued at 317 PM EDT Sat Jul 12 2025 DISCUSSION... Broken line of strong to marginally severe thunderstorms went up on the prefrontal trough around noon, earlier and more extensive than many of the hires solutions. Dew pts dropping into the mid to upper 60s and surface ridging moving in late this afternoon has pretty much ended the severe threat, as mid level cold pool and much better wind shear over Western Great Lakes will not arrive in time before the sun sets. Still, the cold front may be able to muster a couple more showers and thunderstorms in the evening with some residual low instability left over. Upper level trough axis swings through tomorrow, but extremely dry mid levels (40-50 C dew pt depressions at 700 MB) look to prevent any activity from going up, except perhaps right near the southern Michigan border. Upper level ridge (591-592 DAM at 500 MB) axis then builds over the region early next, promoting dry but hot weather, with temps likely reaching 90 degrees on Tuesday. A wet pattern then looks to be setting up for Wednesday-Thursday as moisture streams up from Gulf Coast States/Southern Plains, in response to a fairly strong upper level wave/trough swinging through the northern Rockies and into the Western Great Lakes by Thursday. Euro ensembles indicating at least a 60 percent chance of a tenth or inch or more of qpf in Wednesday-Thursday time frame. MARINE... The thunderstorm threat has generally receded although some isolated development remains possible through the evening hours. Otherwise, dry conditions prevail in the wake of the ongoing cold front passage which brings light winds with gust potential holding below 20 knots. The next chance for showers and thunderstorms will arrive through the midweek period by Wednesday as an upper-level disturbance arrives over the Great Lakes. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...Small Craft Advisory until 10 PM EDT this evening for LHZ421-422. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....AA DISCUSSION...SF MARINE.......AM You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.