Area Forecast Discussion
Issued by NWS Miami, FL
Issued by NWS Miami, FL
207 FXUS62 KMFL 281556 AFDMFL Area Forecast Discussion National Weather Service Miami FL 1156 AM EDT Thu Aug 28 2025 ...New UPDATE, AVIATION... .KEY MESSAGES... Updated at 1146 AM EDT Thu Aug 28 2025 - Confidence continues to increase in a forecast of heavy rainfall across the metro areas of South Florida this upcoming weekend into early next week. Localized higher rainfall amounts over a short period of time may result in urban flooding. - Scattered to numerous thunderstorms over the next several days may produce frequent to excessive cloud to ground lighting, gusty winds, and small hail. While the greatest coverage of storm activity should be during the afternoon hours, timing may vary from day to day. && .UPDATE... Issued at 1146 AM EDT Thu Aug 28 2025 The midnight shift discussion/synopsis remains on track. Additional messaging in the form of the key messages above and a informed design social media graphic on X/Facebook have been shared thus far today. As the pattern continues to evolve, the sharing of additional messaging and fine-tuning of NWS Miami products will occur. While forecasted rainfall totals will continue to oscillate in values, the main item to convey to the reader is that heavy rainfall that occurs over a short period of time over a vulnerable poor drainage area may result in urban (potentially flash) flooding regardless of antecedent conditions. Stay tuned. && .SHORT TERM... (Today through Friday) Issued at 112 AM EDT Thu Aug 28 2025 Large scale troughing continues to cover most of the Eastern Seaboard, extending from a deep low pressure centered in the Great Lakes region. This trough will continue to try to dig further south, but in the short term period the trough axis where the primary positive vorticity and energy is located is likely to stall out in northern Florida. As a result, the weather for the end of this week will still primarily be diurnally driven with shower and thunderstorm development being a result of increased surface heating and the sea breezes advancing inland. With ongoing weak flow at the surface and in the low levels of the atmosphere, the sea breezes will be able to push well inland and cause the most coverage of showers and storms to develop over the interior. Primary hazards will be potential for some strong wind gusts with the few stronger storm cores that develop as well as heavier downpours. High temperatures for Thursday and Friday are expected in the low to mid 90s with lows Thursday night ranging from the low 70s around the Lake O region to the mid and upper 70s for the coastlines and metro areas. && .LONG TERM... (Friday night through Wednesday) Issued at 112 AM EDT Thu Aug 28 2025 Heading into the weekend, the deep trough covering the Eastern Seaboard will continue to dig southwards with its axis likely pushing into South Florida over the weekend. At the same time as the trough digs southwards, surface low pressure is expected to develop near the Florida Panhandle and northeastern Gulf along with a steady stream of positive vorticity impulses streaming across South Florida in association with the synoptic trough. The surface low will continue to expand and shift eastward with its circulation covering the areas between the western Atlantic and the eastern Gulf, essentially encompassing GA, FL and the Carolinas. This surface low as well as the longwave trough will provide daily energy and vorticity advection for lift that will help assist in the development of showers and thunderstorms. Coverage has the potential to become widespread given ample moisture available (PWATs of 1.8- 2.2 or higher inches). Overall, this setup is creating an interesting situation where hydro concerns will arise given the risk for repeated rounds of moderate to heavy rainfall not just in a single day but repeated on a daily basis. As the weekend and early next week time periods enter the short term forecast picture, details on QPF and other important information will become much more clear. For now, the main message is that there will be increased risk for moderate to heavy rainfall causing potential hydro concerns across South Florida over the weekend and through the first half of next week. Temperatures during the extended period will start to decrease slightly as we are looking at an increase in rain coverage and cloud cover. High temperatures are expected in the upper 80s to low 90s each day. Overnight lows will range from the low to mid 70s for the lake and Gulf coast regions to the upper 70s for the east coast metro. && .AVIATION... (18Z TAFS) Issued at 1146 AM EDT Thu Aug 28 2025 Winds will veer onshore remaining light in nature today with SHRA/TSRA developing across inland locales. This activity may drift back towards the east coast terminals during the mid to late afternoon hours which may result in sub-MVFR cigs/vis. TEMPOs have been maintained and may need to be adjusted based on radar trends. && .MARINE... Issued at 112 AM EDT Thu Aug 28 2025 Benign conditions are expected to continue across the local waters through the end of the week and into the weekend. A gentle SE breeze will be in place with scattered showers and storms possible each day. Showers and storms may result in occasional locally stronger winds and elevated seas. && .PRELIMINARY POINT TEMPS/POPS... Miami 91 78 91 77 / 60 50 80 60 West Kendall 91 76 91 75 / 70 40 80 60 Opa-Locka 93 78 92 77 / 60 50 80 60 Homestead 91 77 91 76 / 60 50 80 60 Fort Lauderdale 91 78 91 77 / 60 60 80 60 N Ft Lauderdale 92 79 92 77 / 70 60 80 60 Pembroke Pines 93 78 94 77 / 60 50 80 60 West Palm Beach 92 77 92 76 / 60 60 80 60 Boca Raton 92 78 92 76 / 70 60 80 60 Naples 93 77 92 77 / 60 50 70 40 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && $$ SHORT TERM...Redman LONG TERM....Redman AVIATION...Hadi