Area Forecast Discussion
Issued by NWS Miami, FL
Issued by NWS Miami, FL
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728 FXUS62 KMFL 211412 AFDMFL Area Forecast Discussion National Weather Service Miami FL 1012 AM EDT Sat Sep 21 2024 ...New UPDATE... .UPDATE... Issued at 1005 AM EDT Sat Sep 21 2024 The 12z MFL sounding shows a relatively drier atmosphere which may limit coverage but convection has still been able to develop and progress in an isolated fashion near sources of available surface moisture. With the sea breezes advancing inland later today, expect convective activity and coverage to perk up a bit as forecast. Cannot rule out an isolated stout storm or two today with a localized threat of heavy rainfall which could lead to nuisance flooding over some of the inland suburbs in the afternoon or early evening if storms linger over the area for too long. Otherwise, no major updates are anticipated through midday. Have a wonderful Saturday! && .SHORT TERM... (Today through Sunday) Issued at 310 AM EDT Sat Sep 21 2024 Models were very successful in depicting the drying trend expected for the weekend as there was significantly less convection and shower coverage yesterday compared to previous days. Ensembles and GFS remain consistent in keeping weak, generally NE sfc flow across SoFlo through the rest of the weekend in the wake of a FROPA. Meanwhile, a weak mid level trough still lingers over the SE CONUS and northern FL, but will begin pushing a little further southeast later today as high pressure expands over the TX region. Drier conditions should prevail today and tomorrow with highest POPs down into the 20-30 percent range each afternoon, with best chances over the southern-most portions of the peninsula. Daytime heating and sea breeze/outflow boundaries could again provide enough lifting for a few storms to develop. Pressure gradients remain weak during the weekend with sfc wind speeds in general remaining below 10kt. With less cloud cover and fewer showers, temperatures will climb back into the low 90s area-wide each afternoon. Heat indices are expected to remain above seasonal climo, with max values in the 100 to 103 degrees range, just below advisory criteria. && .LONG TERM... (Sunday night through Friday) Issued at 310 AM EDT Sat Sep 21 2024 Moving into the new week, an expansive mid-level ridge will stretch across the Gulf of Mexico and into southeastern CONUS as the lingering trough drifts into the Atlantic. This ridge will be the primary synoptic influence in the weather pattern during the early to middle portion of the week as it gradually shifts eastward and centers over South Florida. At the surface, as high pressure strengthens to the north, east-northeasterly wind flow will gradually increase early next week due a tight pressure gradient from a stalled frontal boundary over the Florida Keys and the high pressure to the north. Mid-level drier air will work in from the north bringing the PWAT values down to 1.5-1.8" over the region on Monday and Tuesday. While this will help to reduce shower and thunderstorm chances each day, the stalled frontal boundary to the south will keep a sufficient supply of low-level moisture in the southern half of the Peninsula. With the assistance of sea breezes and outflow boundaries, this will support daily scattered showers and isolated thunderstorms across the region, with the best chance along, and to the south of, Alligator Alley. Temperatures will be just above seasonal normals with high temperatures in the upper 80s to low 90s, and mid-90s in far SW FL. While the heat indices will likely reach the triple digits, the drier air should provide a relief from heat advisories due to dew points dropping into the low to mid 70s, especially in the first half of the week. Looking further into the week, confidence continues to run low and uncertainty rises as guidance still remains in disagreement in regards to a potential tropical disturbance. Models vary about the future of a Central American Gyre, which may consolidate into a more defined area of low pressure over NW Caribbean and southern GOMEX. The latest guidance remains in disagreement in its intensity and placement of this feature during this time frame as there is currently no area of low pressure to track. Until an area of low pressure forms, guidance will remain poor in resolving this potential disturbance until something trackable actually develops. As of 2AM, The National Hurricane Center currently gives a 60 percent chance of development over the next 7 days, with early next week the potential time. This will continue to be monitored as the week progresses. Regardless, there is indication of a wet latter half of the week as moisture will try to advect back into the region, which will increase daily showers and thunderstorm chances.| && .AVIATION... (12Z TAFS) Issued at 755 AM EDT Sat Sep 21 2024 Light and variable wind will become more onshore as late morning into the afternoon. A few storms this the afternoon and early evening may result in brief flight restrictions and erratic winds, but mainly VFR conditions should prevail today. && .MARINE... Issued at 310 AM EDT Sat Sep 21 2024 Generally light winds continue today and Sunday with a decaying frontal boundary lingering south of the state. Showers and thunderstorms will be much less active as drier air continues to filter from the north behind a frontal passage. Can`t rule out a few thunderstorms, mainly in the afternoon hours. Brief periods of rough seas and gusty winds may accompany any thunderstorm that forms. && .BEACHES... Issued at 310 AM EDT Sat Sep 21 2024 Minor to moderate coastal flooding continues during periods of high tide today. These elevated tides will continue to affect all coastal areas of South Florida late this afternoon. A coastal flood advisory remains in effect. Conditions should begin to improve on Sunday as northerly swell and the tidal influence decreases, but we could still see some minor coastal flooding during high tide. Additionally, a moderate risk of rip currents continues for the Palm Beaches during the next couple of days. NAPLES HIGH TIDE TIMES...3:58 PM this afternoon LAKE WORTH HIGH TIDE TIMES...11:15 AM today && .PRELIMINARY POINT TEMPS/POPS... Miami 90 76 90 77 / 40 20 30 20 West Kendall 92 74 92 75 / 50 20 30 20 Opa-Locka 91 76 92 77 / 40 20 30 20 Homestead 90 76 90 76 / 40 20 30 20 Fort Lauderdale 89 76 90 78 / 30 20 20 20 N Ft Lauderdale 90 76 90 78 / 30 20 20 20 Pembroke Pines 92 76 93 78 / 40 20 20 20 West Palm Beach 90 76 90 77 / 30 10 20 30 Boca Raton 90 76 91 78 / 30 20 20 30 Naples 92 75 91 76 / 40 20 20 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...Coastal Flood Advisory until 5 PM EDT this afternoon for FLZ069- 075-168-172>174. AM...None. GM...None. && $$ SHORT TERM...17 LONG TERM....JS AVIATION...RAG