textproduct: Miami - South Florida

KEY MESSAGES

Updated at 421 AM EDT Sat Sep 5 2026

- An active weather pattern remains in place through the weekend and into early next week as scattered to numerous showers and thunderstorms will develop each day. The strongest storms could contain heavy downpours and frequent lightning. - Heavy downpours with high rainfall rates combined with slow moving storms will increase the risk for localized flooding especially over the urban and poor drainage areas. - High temperatures will generally rise into the lower 90s across most of South Florida through the holiday weekend, creating widespread Moderate HeatRisk.

SHORT TERM

(Today through Sunday) Issued at 421 AM EDT Sat Sep 5 2026

A mid/upper-level ridge remains anchored over the central CONUS while a broad trough digs southward over the Eastern Seaboard. At the surface, high pressure centered east of the Florida peninsula persists through today, keeping light southeasterly flow in place. Meanwhile, a moist tropical airmass remains entrenched across South Florida, as evidenced by the 00Z MFL sounding and recent ACARS data showing PWATs between 2.3-2.4 inches, above the 90th percentile for early September. With deep moisture and weak upper level forcing in place, expect scattered to numerous showers and thunderstorms to develop again today, forced mainly by sea-breeze and mesoscale boundary interactions. Coastal showers are possible in the morning before activity shifts toward the interior and SW Florida during the afternoon hours. With 500-mb temperatures remaining above normal (hovering around -6C) and weak steering flow, the primary hazards will be frequent lightning and localized flooding in urban and poor- drainage areas due to slow storm motion and high rainfall rates. Accumulations of 0.5-1.5 inches are expected across the region, with localized higher amounts of up to 4 inches. Isolated shower and thunderstorm activity may linger over the coasts and nearshore waters briefly after sunset before dissipating overnight.

By Sunday, a weak frontal boundary digging southward over the southeastern US and western Atlantic will nudge the western Atlantic high pressure ridge axis southward. This will result in winds shifting south-southwesterly across South Florida, keeping the Atlantic sea breeze pinned closer to the East Coast. Convection will start to develop in Southwest Florida in the morning before shifting towards the East Coast in the afternoon. Abundant moisture with PWATs above 2 inches will continue to support scattered to numerous showers and thunderstorms through the day.

High temperatures will run slightly above average, reaching the low 90s across the region. Overnight lows will fall into the low to mid- 70s across the interior, remaining in the upper 70s along the coasts. A moderate HeatRisk through all urban areas each day this weekend, mitigated locally where afternoon storms manage to bring temporary relief.

LONG TERM

(Sunday night through Friday) Issued at 421 AM EDT Sat Sep 5 2026

Mid/upper level troughing lifts northeastward into the Atlantic early next week as ridging builds across the eastern CONUS. South to southwesterly winds persist through Monday across South Florida before giving way to a light easterly flow by midweek as high pressure builds at the surface over the western Atlantic. Convective initiation is expected to remain primarily sea-breeze driven through the rest of the week, with the highest chances of showers and thunderstorms shifting over the interior and east coast metro areas during the afternoon and evening hours through Monday. As easterly wind flow become established heading into the middle of the week, the highest chances of showers and thunderstorms will then focus over the interior and Southwest Florida. While strong thunderstorm development will remain fairly limited through the middle of the week, an abundance of moisture will still remain in place across the region. This will allow for heavy downpours with high rainfall rates to continue with the stronger storms which could lead to localized flooding over the urban and low lying areas.

Temperatures will continue to be hot and muggy through the middle of the week, with highs generally rising into the lower 90s across most areas, however, some mid 90s will remain possible over the interior portions of Southwest Florida. Overnight lows will be in the upper 70s along the coasts and low to mid 70s across the interior.

AVIATION

(06Z TAFS) Issued at 142 AM EDT Sat Sep 5 2026

Light and variable winds along with VFR conditions will continue overnight for all terminals. Into Saturday afternoon, a prevailing SE flow will set up for the eastern terminals while the Gulf breeze shifts winds SW for APF. For all terminals, scattered showers and t- storms are forecast to begin moving on shore in the early afternoon as the sea breeze pushes in, eventually favoring the interior and SW Florida later in the afternoon. Into Saturday evening, winds will return to light and variable overnight.

MARINE

Issued at 421 AM EDT Sat Sep 5 2026

A gentle southeasterly breeze will prevail across the Atlantic waters today, while a light southeasterly breeze will shift south- southwesterly across the Gulf waters this afternoon. Winds across all local waters will turn south-southwesterly by the second half of the weekend into early next week. Seas across the Atlantic and Gulf waters will remain at 2 feet or less through the weekend. Scattered to numerous showers and thunderstorms will be possible each day through the weekend and into early next week.

PRELIMINARY POINT TEMPS/POPS

Miami 90 78 90 79 / 60 20 60 30 West Kendall 90 77 90 76 / 70 20 60 30 Opa-Locka 90 79 91 77 / 70 20 60 30 Homestead 91 77 91 77 / 70 20 60 30 Fort Lauderdale 90 78 90 78 / 60 20 60 40 N Ft Lauderdale 91 78 91 79 / 60 20 60 40 Pembroke Pines 90 77 90 78 / 70 20 60 30 West Palm Beach 92 76 92 76 / 70 20 50 40 Boca Raton 90 77 90 78 / 60 20 50 40 Naples 90 77 90 78 / 50 30 40 40

MFL WATCHES/WARNINGS/ADVISORIES

FL...None. AM...None. GM...None.