Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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509 FXUS63 KDTX 030720 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 320 AM EDT Fri May 3 2024 .KEY MESSAGES... - Numerous showers hang around today, with a chance of non-severe thunderstorms. - High pressure fills in briefly on Saturday offering drier weather ahead of the next weak cold front that tracks through SE Michigan early Sunday morning. - Seasonably warm temperatures expected through early next week with high temperatures in the low to mid 70s. && .DISCUSSION... Large upper level low/trough over Central North American early this morning, with the center along the northern Minnesota border. The 500 MB low (~540 DAM) will track off to the northeast, reaching Hudson Bay Saturday morning. Deep southwest flow will maintain above normal temperatures over southeast Michigan right through the weekend. Moisture advection has peaked out with the broad 850-700 MB Theta-E ridge axis extending north, through the Central Great Lakes. Still looks like lingering showers around today with possible thunderstorms as a ribbon of upper level PV approaches from the southwest. Severe weather not expected with weak mid level lapse rates and MLcapes under 750 J/kg. Height rises/surface ridging expected on Saturday, leading to mainly dry conditions during the day. Low clouds trapped underneath subsidence inversion, with perhaps a bit of drizzle/very light showers toward the southern Michigan border where the higher dew pts reside. Weak height falls/cold front then on track to move through through Saturday night, worthy of chance pops, despite the bulk of the forcing over northern Great Lakes. Western confluent upper level flow Sunday preceding an upper level ridge axis arriving early next week, supporting at least a 48 hour window of dry and pleasant weather. && .MARINE... A low pressure system will then track through the northern Great Lakes today pulling the warm front up through the region early in the day. This will allow winds to flip around to the south-southwest which will bring in a warmer airmass, helping to keep gusts down. Scattered showers and thunderstorms will focus on this morning warm frontal passage and may persist into the afternoon. Showers and thunderstorms then increase coverage once again in the evening as the cold front gets pulled through the region. Brief area of high pressure brings quieter weather on Saturday. Winds will flip around to the northeast behind the cold front tonight, but the area of high pressure will keep winds below 20 knots. Southerly winds will redevelop Saturday night ahead of the next cold front that will sweep through Sunday, but will turn northwesterly behind the front Sunday afternoon. && .PREV DISCUSSION... Issued at 1157 PM EDT Thu May 2 2024 AVIATION... Clusters of elevated showers and isolated thunderstorms continue over SE Mi late tonight through the morning. Ongoing activity along and north of the warm front combines with additional showers and storms moving in from the IL/southern Lake Mi area as the front moves very slowly from northern IN and western OH into southern Lower Mi. Earlier nocturnal timing of rainfall contributes to expansion of MVFR ceiling in and around the warm front as it moves northward and eastward during the morning followed by a similar cloud field quickly followed by the associated cold front. The cold front is set to move through SE Mi during afternoon also providing a focus for showers and scattered storms until exiting eastward by Friday evening. For DTW/D21 Convection... An isolated and elevated thunderstorm occurs late tonight among scattered to numerous showers across SE Mi. The storms will have ordinary intensity through the morning until daytime instability builds up in the afternoon. A renewed time window for thunderstorms then occurs mid to late afternoon as a cold front moves through the region. Scattered coverage occurs among numerous showers along the front, although strong to severe storms are not expected. DTW THRESHOLD PROBABILITIES... * Low for thunderstorms tonight and Friday. * Moderate for ceiling 5000 ft or less Friday. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ DISCUSSION...SF MARINE.......SF AVIATION.....BT You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.