Area Forecast Discussion
Issued by NWS Miami, FL
Issued by NWS Miami, FL
981 FXUS62 KMFL 181103 AFDMFL Area Forecast Discussion National Weather Service Miami FL 703 AM EDT Mon Aug 18 2025 ...New AVIATION... .SHORT TERM... (Today through Tuesday) Issued at 102 AM EDT Mon Aug 18 2025 Monday begins just like any other typical summertime day in South Florida. Very weak east-southeast flow prevails early in the day as mid to upper level ridging retreats and leaves South Florida in the absence of significant synoptic influence. As the day progresses, Hurricane Erin slowly enters the picture and surface flow tries to attain a more northerly direction over local waters, while flow remains extremely weak over land. Sea breezes are expected to be the primary driver of convection as Hurricane Erin remains well towards the southwest, although as sea breezes progress inland, northeast flow will develop across the eastern half of the area with northwest flow over the western half of the area. This will create kind of a unique scenario where convection begins to develop along the sea breezes and slowly pushes towards the south. Overall, with such weak background flow storm movement will be slow, and close to the metro areas. Convection will likely begin across far western parts of the east coast metro areas and very slowly progress inland and eventually towards the south as the afternoon and evening progress. There will likely be a sharp gradient in cloud cover, with sunshine remaining only over the immediate coastal areas and barrier islands. Generally quiet conditions should prevail overnight Monday into Tuesday, although some high-res guidance is hinting at a slower halt to convection, with some activity lingering into the first half of the night. On Tuesday, Erin continues to propagate northward and is forecast to make its closest pass to the peninsula to the east. This is where we begin to see slightly stronger and more uniform northerly flow develop across the area. A few coastal showers will be possible during the morning hours, but shower and thunderstorm activity will begin to increase across land areas by the early afternoon hours as daytime heating is maximized. A similar evolution is expected through the day with a general southerly motion to the showers and thunderstorms. As the day progresses, we should see surface flow beginning to veer more northwesterly which will possibly advect the focus of convection across the far southern portions of the area, including more of the Miami-Dade and Broward metro areas than on Monday. All of this is dependent on the progression of Hurricane Erin, and slight deviations in the storm speed or motion could change timing for wind shifts across Florida, which would impact the exact propagation of local thunderstorms. && .LONG TERM... (Tuesday night through Sunday) Issued at 102 AM EDT Mon Aug 18 2025 Hurricane Erin remains the primary synoptic feature through much of the long term period. As this system continues northeastward, surface flow across South Florida veers more westerly by Wednesday afternoon and will remain west-southwest through much of the period. The only exception is along the immediate east coast where a sea breeze will attempt to develop each afternoon and we could see brief periods of southerly or even southeasterly winds in these regions. A drier airmass moves in on Wednesday facilitated by Hurricane Erin`s circulation which could act to reduce rain chances during the mid-week period. PWATs will range from 1.6 to 1.7 inches, which could support a few isolated showers and storms but mostly sunny conditions should prevail overall on Wednesday. On Thursday and Friday a bit more moisture is able work into the area, especially over the Lake Okeechobee region including Glades, Hendry and Palm Beach counties, and this is where we should see most showers and storms on Thursday and Friday afternoon, potentially progressing eastward towards towards coast by the evening as westerly flow continues to prevail, albeit very light. Heading into the weekend, Hurricane Erin`s influence begins to weaken leaving South Florida without much synoptic influence at all. Surface flow weakens significantly which should allow for a more typical sea breeze pattern to dominate for Saturday and Sunday, with an eastern breeze able to push inland and focus convection across interior and Southwest portions of the area. Temperatures should range from the low to mid 90s through the period, with heat index values ranging in the low 100s to around 105, potentially dancing around Heat Advisory criteria, so this potential will be monitored each day. && .AVIATION... (12Z TAFS) Issued at 702 AM EDT Mon Aug 18 2025 Scattered showers and thunderstorms this afternoon into early evening may result in brief flight restrictions. Light and variable winds this morning becoming easterly around 10 kts, with a westerly Gulf breeze this afternoon at APF. && .MARINE... Issued at 102 AM EDT Mon Aug 18 2025 Pattern change begins Monday as distant Hurricane Erin`s outer circulation begins veering winds across Atlantic waters to a more north-northeasterly direction. Light and variable winds across Gulf waters to begin the day, and will be veering to a more northwesterly direction by the afternoon. Winds will remain northeasterly for the first half of Tuesday, but will be veering to a more north- northwesterly direction through the day on Tuesday. Wave heights remain at one foot or less for Atlantic waters on Monday and Gulf waters on Monday and Tuesday. Wave heights increase to 3-4 feet across northern Atlantic waters on Tuesday. The only exception is around thunderstorms, which could provide brief periods of rough seas and gusty winds. With the passage of Erin to the east of the Florida peninsula mid- late week, local Atlantic waters could see an increasing north- northeasterly swell during this time period. && .BEACHES... Issued at 102 AM EDT Mon Aug 18 2025 Increasing swell from Erin is expected as early as Tuesday, but more likely mid to late week. This will result in an increasing rip current threat for the Atlantic beaches and possible high surf concerns for Palm Beach county. && .PRELIMINARY POINT TEMPS/POPS... Miami 93 80 93 78 / 30 20 60 30 West Kendall 94 77 93 76 / 30 30 60 30 Opa-Locka 95 79 95 78 / 30 20 60 30 Homestead 93 78 93 78 / 30 30 60 30 Fort Lauderdale 92 80 92 78 / 30 30 60 30 N Ft Lauderdale 93 80 93 78 / 30 30 50 20 Pembroke Pines 96 80 96 79 / 30 20 60 30 West Palm Beach 93 78 93 77 / 30 30 50 20 Boca Raton 95 78 94 77 / 30 30 50 20 Naples 93 78 93 79 / 50 30 60 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && $$ SHORT TERM...Rizzuto LONG TERM....Rizzuto AVIATION...CMF