FXUS63 KDTX 230948 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 548 AM EDT Sun Aug 23 2026 .KEY MESSAGES... - Breezy and cooler conditions arrive today with scattered showers through tonight. - Dry weather Monday into Tuesday with a warming trend. The next chance of showers and storms is possible late Wednesday and Thursday. && .AVIATION... Low pressure strengthening on the Ontario/Quebec border fuels moderate NW wind across the western Great Lakes today. The wind carries a cooler air mass into the region but one that still has a usable amount of moisture as shown by surface Td holding in the 50s. The boundary layer thermal/moisture profile supports increasing coverage of borderline MVFR/VFR stratocu once the sun applies some surface heating during the morning. These clouds build into a deeper cumulus field and then into scattered showers and isolated thunderstorms this afternoon and early this evening. The Ontario/Quebec low pressure system is nearly stationary tonight which keeps the associated cloud field overhead or nearby to the east of the terminal corridor. Consensus of model guidance favors low end VFR ceiling late tonight and Monday morning. D21/DTW Convection... Low potential for an isolated thunderstorm this afternoon and evening. .DTW THRESHOLD PROBABILITIES... * Moderate to high for ceiling 5000 feet or less today and tonight. * Low for an isolated thunderstorm this afternoon and evening. && .PREV DISCUSSION... Issued at 318 AM EDT Sun Aug 23 2026 DISCUSSION... A series of embedded shortwave maxima will dig directly into the central Great Lakes bolstering a closed 560 dam H5 trough through Monday night. Progs show 850mb temperatures bottoming out at +7C which will largely support high temperatures in the lower to upper 70s range the next couple of days, some 3 to 6 degrees below normal. Beefiest of the absolute vorticity maxima will arrive this afternoon with a direct path into the cwa while turning to a negative tilt. Forecast environmental profile shows main limiting factor for today will be very modest midlevel lapse rate structure at 5.5 C/km preceding the absolute vorticity. NWP supports upward vertical motion beginning to deepen after 18z with height falls rapidly pushing to the southeast of Southeast Michigan. Will require a good amount of lift to fight off the subsidence and all signs suggest shower and possible thunderstorm activity being relegated to the far southeast cwa mainly between 21-00z. Guidance looks again underdone. Again, modest lapse rates do not suggest much CAPE density this afternoon and no severe weather is expected. Closed low pushes eastward leading to 1000-500mb geopotential height rises and surface high pressure Monday. Only real item of note will be the potential for early to mid morning rain showers possible for the northern Thumb region/Huron County as good model signal exists for highly cyclonic flow and confluence downwind of Saginaw Bay and Lake Huron. Great day Tuesday for outdoor interests with high around 80 and surface dewpoints in the 50s. High confidence in very favorable weather with upper level confluent flow supporting strong surface ridging. Broad upper level jet streak and associated absolute vorticity wave packet is forecasted to push into the Great Lakes region Wednesday and Thursday. Uncertainty exists on most likely time window for precipitation onset as there will be a dry column preceding the wave. Temperatures are expected to be near late August averages Thursday and Friday. MARINE... Breezy post-frontal northwest flow to persist today and into the better part of tomorrow as cooler air is ushered into the Great Lakes. Sustained winds of 20 to 25 knots with gusts up to 30 knotsare expected, the strongest of which will be found across north- central and central Lake Huron where the fetch is more favorable. Some isolated gust potential to low-end gales cannot be ruled out for Lake Huron, but will preclude any Gale headlines given very low confidence to achieve any prolonged period of gales. Otherwise, rain showers and some isolated thunderstorms will be possible today along with a very low chance for a waterspout, most favorable across Lake Huron. High pressure will start to build into the region late tomorrow and will settle over the Great Lakes by Tuesday. Process of this high pressure moving in will start to relax wind speeds and gusts, leading to light winds by Tuesday. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...Beach Hazards Statement through Monday afternoon for MIZ049. Lake Huron...Small Craft Advisory until 4 PM EDT Monday for LHZ421-441>443. Small Craft Advisory until 4 AM EDT Monday for LHZ422. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....BT DISCUSSION...CB MARINE.......CB You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.