FXUS63 KDTX 270834 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 434 AM EDT Mon Oct 27 2025 .KEY MESSAGES... - Becoming more seasonable and dry through the first half of the week. - Rain chances increase Wednesday night and Thursday as temperatures trend below normal to close out the workweek. && .AVIATION... Narrow line of clouds (high MVFR) over western Lake Erie will continued to be monitored, as a northward drift remains in play this morning toward YIP/DTW. Confidence remains low, especially with respect to BKN ceilings. Otherwise, strong surface high pressure holds over Eastern Canada, maintaining clear-mostly clear skies and low level easterly winds. Increased mixing depths during the afternoon may yield a wind gust up to 20 knots. For DTW/D21 Convection...No thunderstorm activity this TAF period. DTW THRESHOLD PROBABILITIES... * Low for cig aob 5000 feet this morning. && .PREV DISCUSSION... Issued at 359 AM EDT Mon Oct 27 2025 DISCUSSION... A ridge axis extending across the Great Lakes will maintain dry and mostly cloud-free conditions for the majority of Southeast Michigan today. Once again, a climatologically cool start to the morning as several rural areas are currently reporting sub-freezing temperatures. Largely uninhibited diurnal insolation, coupled with a slight increase in 850 mb temperatures, should send readings back into the 50s for the midday hours. One noticeable difference today compared to yesterday will be gustier winds, as peak afternoon speeds could exceed 20 mph once stronger 925 mb flow drifts north of the Ohio Valley. Constricted easterly gradient wind subsequently resides near the Michigan/Ohio border. Also expect a higher cloud fraction for portions of the southern four counties given the favorable fetch along the long axis of Lake Erie. A bit milder tonight with a few clouds around, so most areas should stay above freezing. The forecast area remains situated between 1035 mb surface high pressure centered over the mid-section of Quebec, and a deepening surface low west of the Mississippi. This configuration is attributed to an increasingly ageostrophic jet streak racing into the southern Plains, which will eventually impact Southeast Michigan. However, Tuesday looks to be another benign day for Southeast Michigan amidst a brief period of split-flow. Sub- saturated easterly flow lingers, although daytime gustiness should increase with favorable positioning of a low-level jetlet. Some uncertainty exists regarding high temperatures Tuesday due to conflicting guidance on thermal advection (a proportional mix of positive and negative solutions). Growing model consensus in the robust upstream shortwave trough interfacing with a retrograding VortMax extending from The Northeast. This then leads to rapid enhancement of the primary low late Tuesday night into Wednesday. Deterministic and ensemble solutions are better aligned in a longer residence time over The Southeast before ejecting due north across the Virginias on Thursday. This lends confidence in keeping the system's precipitation shield just south of Michigan during the midweek period. Automated NBM guidance is slow in making this adjustment, therefore outgoing PoPs are a bit aggressive for Wednesday. The first chance for more meaningful rainfall arrives on Thursday. As of now, the western extent of such rain remains a question which implies some parts of the CWA could see next to nothing given the current trajectory of the system. Forecast adjustments are forthcoming. MARINE... The central great lakes will remain positioned between high pressure centered over Quebec and low pressure lifting across the midwest during the early week period. This will maintain an extended period of easterly flow during this time. Sustained winds of generally 10 to 20 knots, with intermittent gustiness to 25 knots at times. The prevailing onshore flow will bring increasing wave action along the nearshore waters. Small craft advisory conditions for elevated wave heights expected starting Monday evening and likely lasting into Wednesday. No rain is in the forecast through at least Tuesday. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...Small Craft Advisory from 8 PM this evening to 4 PM EDT Wednesday for LHZ421-441>443. Lake St Clair...None. Michigan waters of Lake Erie...Small Craft Advisory from 8 PM this evening to 4 PM EDT Tuesday for LEZ444. && $$ AVIATION.....SF DISCUSSION...KGK MARINE.......MR You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.