Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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333 FXUS63 KDTX 110242 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 1042 PM EDT Sat Aug 10 2024 .KEY MESSAGES... - Below normal temperatures this weekend with breezy west winds into this evening and then again on Sunday. - Dry or mainly dry weather, with just a slight/low chance of brief showers on Sunday, and sporadic brief times next week. - Near normal temps expected next week. && .AVIATION... Unsettled pattern within cyclonic west/northwest flow will maintain periods of lower VFR cigs into tonight, but with some scattering out possible in time. A few showers may also encroach on KMBS/KFNT/KPTK. An additional diurnal component should then lead to a period of BKN cigs again Sunday. Westerly flow will of 10 knots or less overnight with gusts to 20 or more knots by midday Sunday with better mixing. For DTW/D21 Convection... No thunderstorms are expected. DTW THRESHOLD PROBABILITIES... * Low for cigs at or below 5000 ft Sunday afternoon. && .PREV DISCUSSION... Issued at 301 PM EDT Sat Aug 10 2024 DISCUSSION... Water vapor imagery this afternoon shows the well-defined upper low spinning across the Upper Great Lakes and Ontario this afternoon, with multiple lobes of vorticity rotating about the main circulation. This upper low will slowly move southeast across Ontario and into Quebec over the rest of the weekend. As a few lobes of vorticity and the pocket of cooler air aloft move over portions of southeast Michigan on Sunday, showers are possible from mid-late morning and into the afternoon hours. High-res guidance show better coverage and a higher potential for numerous showers up across the Thumb region, with more isolated to scattered showers further south. So not everyone will see shower activity on Sunday. As the main upper level trough continues to move towards the Northeast on Monday, large-scale troughing lingers through much of next week as a series of weaker shortwaves dig across the region. Given this pattern, the pocket of cooler air over Michigan will be slow to modify. Thus, expect a warm up back to near-normal (mid- upper 70s) for Monday and then warming a few degrees each day as we head through the end of the week. Precipitation chances for next week are challenging given the numerous shortwaves moving through the region and uncertainty regarding their strength and timing. MARINE... Broad area of low pressure remains spread across Ontario and Quebec while reaching southwest through the Great Lakes. The upper low has several stronger troughs rotating around it, the next which will swing through the region later tonight. This may help to keep a few stronger gusts around later into the night but we`ll continue to monitor observations to see if an extension to the current Small Craft Advisories will be needed. This will be competing against the nocturnal minimum for mixing depths as well as a weakening gradient owning to the area of high pressure sliding up from the south. Expectations are for gusts to continue tonight with occasional gusts to 25 knots possible, then holding more around 20 knots on Sunday. Expansive ridge then builds across the Great Lakes Sunday night and persists through the start of the week. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....DG DISCUSSION...JA MARINE.......DK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.