


Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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823 FXUS63 KDTX 160931 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 531 AM EDT Mon Jun 16 2025 .KEY MESSAGES... - Warming trend continues today into tomorrow. - Increasingly muggy conditions will support thunderstorm chances tomorrow and Wednesday. - There is a Slight Chance for severe weather late Wednesday afternoon into Wednesday night along with a Marginal Risk for excessive rainfall for Wednesday and Wednesday night. && .AVIATION... Higher pressure to bring another round of VFR conditions under sct-bkn upper-level cirrus. There will be some subtle low-level convergence maximized across KPTK-FNT this afternoon and coupled with steep low-level lapse rates, brings the potential to see sct-bkn cu that hold aoa 5kft. Otherwise, winds remain light from the southeast for most locations. A quick flip to east-southeast flow will be possible for KMBS this evening once a weak lake breeze comes off the Saginaw Bay. For DTW/D21 Convection... No thunderstorms expected through this TAF period. THRESHOLD PROBABILITIES... * None && .PREV DISCUSSION... Issued at 407 AM EDT Mon Jun 16 2025 DISCUSSION... Relatively quiet weather to start the work week as a surface high pressure maintains influence across Michigan resulting in another dry day. Winds become more south to southeasterly today as the high pressure eases further east and influence of upstream troughing begins. A warmer airmass begins to creep into Michigan with 850mb temperatures rising a couple degrees helping support daytime highs this afternoon into the lower 80s for much of the area. Warmer airmass and increasing dewpoints will also hold overnight lows tonight holding in the low/mid 60s. Tomorrow will be even warmer with deeper southwest flow taking hold and drawing in an the airmass from the plains. Temperatures as 850mb climb into the mid/upper teens supporting highs in the mid to upper 80s. Muggy conditions will also be felt as dewpoints climb at least into the mid 60s. Tuesday will also see a shortwave and associated surface low tracking across the northern Great Lakes/Ontario and drawing a cold front into Michigan during the afternoon. Weak forcing along the front will support chances for showers and thunderstorms during the day as instability builds. However, the lack of a strong low level jet will offer limited shear for organized convection. DCAPEs approaching 1000 J/kg will at least bring potential for isolated strong downburst winds if convection can gain enough strength. The frontal boundary will stall out and bisect lower Michigan tomorrow night. Precipitation chances look limited for much of the night over southeast Michigan, but the presence of the front and weak forcing warrants at least low end PoPs. Another warm night is in store Tuesday night with overnight lows holding in the mid/upper 60s for much of the area. Wednesday will continue to be the focus for upcoming forecasts given the potential threat of severe weather. The stalled out frontal boundary will become the focus for an organizing low pressure system as a potent wave moves into the region. A warm front will lift through southeast Michigan during the early part of the day. Dewpoints into the upper 60s within the warm sector will have ties to the Gulf supported by solid southwest moisture transport. The arrival of the front will also come with a chance of rain and increased cloud cover early in the day, which adds the typical uncertainty to the potential severe threat that may evolve ahead of the inbound cold front later in the afternoon and evening. That being said, the overall dynamics of this system will support the severe weather potential. Models bringing in a 50-60 knots low level jet in the evening as consensus is beginning to focus the main surface low moving across central/northern lower Michigan in the 00-09Z time frame with some differences in timing and location remaining in the deterministic and ensemble space within said time frame. Any convection early on in this time frame should be able to take advantage of any instability that can hold into the evening. Shear will be plentiful given the presence of the low level jet supporting better organized updrafts. A Slight Risk for severe weather is in place on Day 3. Heavy rainfall will also be possible as PWATS climb to 1.75 inches or greater. A Marginal Risk for excessive rainfall highlights this potential. Thursday will see continued chances for showers and thunderstorms as the main trough moves through the Great Lakes. Friday night into Saturday morning will may see thunderstorm potential again as MCS activity rounds a ridge into Michigan. The ridge then build over the Great Lakes bringing hot and muggy conditions for the weekend. MARINE... Light wind organizes out of the southeast today as the center of eastern Canadian high pressure drifts out over the Atlantic. A surface ridge continues to extend westward into the Great Lakes through the day which maintains dry and stable conditions. A warm front then lifts into the Great Lakes on Tuesday which ushers in a warmer and more unstable air mass on south wind reaching 10 to 20 kt. An unsettled pattern follows through the rest of the week as a series of low pressure systems track through the region. Showers and thunderstorms will be possible each day with potential for strong storms on Wednesday. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....AM DISCUSSION...AA MARINE.......TF You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.