


Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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975 FXUS63 KDTX 140356 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 1156 PM EDT Fri Jun 13 2025 .KEY MESSAGES... - Showers may linger between I-94 and the MI/OH border Saturday morning with decreasing cloud cover from north to south as the day progresses. - Warming trend begins Sunday with highs in the 80s, followed by increasing humidity next week. && .AVIATION... Plume of higher moisture will linger across mainly the Detroit airspace through tonight, north of a low pressure system tracking across the Ohio valley. Gradual decline in cloud base with time overnight will lead to a period of MVFR restrictions across this corridor lasting into Saturday morning. PTK to remain on the northern fringe of this moisture with limited potential to dip out of VFR. Higher based VFR will continue to mark conditions at FNT/MBS tonight, outside of an impacts from the governing low pressure. Lingering MVFR stratus across the DTW/YIP corridor will lift with time Saturday, with a more expansive coverage of sct/bkn VFR diurnal cu likely throughout SE MI during the afternoon. Winds prevailing from the east-northeast through the period. For DTW/D21 Convection... Showers will persist through tonight, but limited instability precludes any potential for thunderstorm development. THRESHOLD PROBABILITIES... * High for ceilings at or below 5,000 feet overnight through early Saturday. Low Saturday afternoon. && .PREV DISCUSSION... Issued at 311 PM EDT Fri Jun 13 2025 DISCUSSION... Cut-off low over Missouri attempts to transition to an open wave, gradually drifting northeastward into the Ohio Valley through the next 48 hours. This will activate the stalled frontal boundary draped across northern IN/OH resulting in some shower activity lifting into portions of Southeast Michigan. At present, a weak lobe of CVA has triggered a broken mesoscale line of light showers which have held together over the last several hours, and continue to inch northward. Added a 15 percent PoP area through he diurnal window before these showers should dissipate. 13.12Z models have trended both earlier and further north with more potent activity this evening and overnight, mainly for locations south of M-59. KDTX returns have increased over Lenawee and Monroe Counties with both ADG and TTF now reporting -RA. Also monitoring low-end thunder potential tonight, but leaning towards a very isolated approach given the lack of dynamic forcing and nil instability north of the boundary. A Slight Chance thunder mention was included with the outgoing forecast. The surface low is progged to track east along the Ohio River tonight while high pressure continues to build southeastward, centering over western Quebec. The boundary shows minimal movement while triggering several rounds of showers and thunderstorms which likely persist Saturday morning and into the midday hours. The more prolonged activity should be confined well south of I-94, moreso near the MI/OH border. Mainly dry conditions return Saturday for the rest of the area with increasing geopotential heights. Clouds clear from north to south which leads to a thermal gradient oriented with the clearing trend. However, showers and thunderstorms likely persist south of I-94 Saturday morning and into the midday hours near the MI/OH border. Daily temperature rises ensue Sunday with 850 mb temperatures ascending into the mid-upper teens (Celsius) and a prolonged stretch of +80F, possibly through the entire week. Split-flow aloft emerges Saturday, lasting into early next week which suppresses widespread shower/storm opportunities. Extended stretch of easterly flow shifts southerly Monday into Tuesday as deep-layer flow orients southwesterly with time. This delivers the first real dose of muggy weather as surface dewpoints climb into the upper 60s, possibly breaking the 70F mark by midweek. This coincides with the next shortwave trough feature tracking across the Midwest. If shear/instability materializes appropriately, thunderstorm activity could become widespread. MARINE... A frontal boundary remains stalled over the Ohio Valley while broad high pressure over northern Ontario gradually shifts into Quebec this weekend. This pattern sustains light northeast wind, generally 15 kt or less, across the central Great Lakes. Enhanced wind funneling down the axis of Saginaw Bay will reach 20 to 25 knots and a Small Craft Advisory remains in effect through tonight. Showers continue spreading across the southern lakes into early Saturday as a weak low tracks along the stalled front to the south. Drier weather follows Sunday as the high pressure builds in from the north. Generally weak flow persists into early next week with warmer and more unstable conditions arriving on south wind Monday and Tuesday. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...Small Craft Advisory until 4 AM EDT Saturday for LHZ421-422. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....MR DISCUSSION...KGK MARINE.......TF You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.