Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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416 FXUS63 KDTX 031722 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 122 PM EDT Fri May 3 2024 .KEY MESSAGES... - Another round of showers and thunderstorms develops along a cold front that will track west to east across the area between roughly 2 PM and 8 PM this evening. Severe weather is not expected. - 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. && .AVIATION... A cold front on pace to advance from northwest to southeast across southeast Michigan mid afternoon through early evening. This front may ofer a modest focus for convective shower development during this time. While an isolated thunderstorm remains possible, the potential appears too limited to highlight given lack of greater instability. Cloud base generally at VFR within the pre-frontal environment, with evidence upstream for ceiling height to lower with time toward MVFR as low level moisture increases in the wake of the front this evening. Some degree of low cloud development and maintenance with an accompanying reduction in visibility expected overnight. Forecast will continue to highlight lower MVFR to IFR restrictions through the early-mid morning hours. For DTW/D21 Convection...Very low potential for a thunderstorm to develop between 21z and 01z. Limited instability precludes a mention in the forecast at this time. DTW THRESHOLD PROBABILITIES... * Low for thunderstorms 21z-01z * Low for ceiling 5000 ft or less through this evening. Medium tonight. && .PREV DISCUSSION... Issued at 1030 AM EDT Fri May 3 2024 UPDATE... Numerous showers and a few thunderstorms are ongoing across the cwa this morning. Lightning observations so far have been rather limited, but a few rumbles of thunder are still possible given observed mid level lapse rates of 6.2 C/km and MUCAPE around 400 J/kg per the 12z KDTX RAOB. Individual storm motion has been SW to NE at roughly 40 mph, while the broader precipitation shield has been moving west to east and is on track to exit into Ontario by early afternoon. Drier conditions thus arrive mid-day, and PoPs have been adjusted accordingly to drop down to chance after between 16- 18z (noon-2pm local). Upstream cold front then looks to reinitiate convective activity this afternoon, with the front currently extending from South Bend to Cheboygan. Timing of the front and associated shower/thunderstorm chances begin in the Tri Cities around 18z (2pm) with a gradual drift eastward toward Detroit by around 00z (8pm). No changes to expected intensity with storms expected to hold below severe limits. Thunderstorms may dissipated before reaching eastern counties of the cwa with the front expected to wash out overhead, and instability waning as diurnal heating ramps down this evening. PREV DISCUSSION... Issued at 320 AM EDT Fri May 3 2024 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. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....MR UPDATE.......MV DISCUSSION...SF MARINE.......DRK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.