textproduct: Miami - South Florida

KEY MESSAGES

Updated at 111 AM EDT Tue Sep 22 2026

- Scattered to numerous showers and thunderstorms expected today. Rain chances remain elevated the rest of the week. - Heavy downpours from the stronger showers and thunderstorms could lead to localized flooding over the urban and poor drainage areas each day.

SHORT TERM

(Today through Wednesday) Issued at 111 AM EDT Tue Sep 22 2026

The mid level cut-off low will be disintegrating further today as it gets absorbed into the broader upper level flow for the middle of this week. At the same time, an upper level shortwave trough will form over the Gulf, which will keep an ongoing wet pattern in place across South Florida. This upper level shortwave is expected to provide some increased jet stream dynamics and advection of vorticity maxima that will be favorable to more widespread convective development across the region. Furthermore, low level flow will be out of a southerly direction since South Florida is on the eastern side of this trough, and thus deep moisture advection will also continue. This brisk southerly flow could result in a pinned Atlantic sea breeze as well, which can create more potential for flooding concerns across the east coast metro areas. PWATs for the period are expected to remain at 2.1-2.4 inches, which is above the 90th percentile for this time of year and will provide plenty of deep moisture for any level of forcing to take advantage of in the production of widespread showers and storms.

Not expecting much of a severe threat given weaker lapse rates and warm mid level temperatures, so the main risk once again will be for areas of flooding caused by excessive rainfall. While general QPF is still only 0.5-1.0 inch for most areas today and 1-2 inches on Wednesday, the deep moisture combined with enough forcing from the trough, daily diurnal processes, and mesoscale boundaries will create the potential for much higher local rainfall accumulations. Add in the potential for slow-moving or training storms along with a pinned sea breeze and we could see much higher rainfall amounts that lead to instances of urban and poor drainage flooding. The latest HREF LPMM signals a potential worst case scenario of 5-7 inches of rain in a short time span along the east coast metro. WPC is continuing to carry a marginal risk for excessive rainfall both today and tomorrow for Southeast Florida with the aforementioned details in place, which corresponds to a 5% risk for locations within 25 miles of a single point to experience flash flooding.

High temperatures through mid-week will range from the upper 80s to near 90 with overnight lows in the low to mid 70s for most areas.

LONG TERM

(Wednesday night through Monday) Issued at 111 AM EDT Tue Sep 22 2026

Late in the week and through this weekend, an upper level trough will dig across the eastern US and enhance across most of the Eastern Seaboard before settling off the New England coast in the western Atlantic. A frontal boundary will push southwards in tandem with the trough strengthening and the front will eventually settle over far southern Florida or the Florida Straits this weekend. As the front stalls, much drier air will advect into Central Florida, but most of this will not make it into South Florida. However, PWATs will still fall to average or below average levels with the lake region seeing the lowest values. With this anticipated less moisture available, shower and thunderstorm coverage is expected to decrease primarily for the lake region. This is reflected with PoPs of 25-40% this weekend near the lake and 50-70% for the southern half of the forecast area. Despite the decrease in PoPs for a lot of the area, the pattern will still remain active and unsettled through the forecast period.

Daily high temperatures each day will continue to reach the upper 80s to near 90 with overnight lows mostly in the low to mid 70s. However, areas near the lake could see temperatures drop into the upper 60s several nights.

AVIATION

(06Z TAFS) Issued at 111 AM EDT Tue Sep 22 2026

Light winds will increase out of a southerly direction today around 5-10kts and may contain a southwesterly component, causing the east coast sea breeze to struggle to advance inland. Overall, this can result in crosswinds and occasional wind shifts from SE to SW at times between 15-21Z. SHRA/TSRA will also develop and are likely across the east coast after 15-16Z through the evening and could cause MVFR/IFR restrictions with variable and gusty winds. Lingering activity is possible into the late evening before activity tapers off and winds become light.

MARINE

Issued at 111 AM EDT Tue Sep 22 2026

A gentle southerly flow is expected across the local waters for the next several days with seas of 2 feet or less. Scattered showers and thunderstorms will continue to develop each day, producing locally hazardous winds and seas.

PRELIMINARY POINT TEMPS/POPS

Miami 88 77 87 76 / 70 50 90 50 West Kendall 87 76 87 75 / 80 50 90 40 Opa-Locka 88 76 87 75 / 70 50 90 40 Homestead 88 76 88 76 / 70 60 90 60 Fort Lauderdale 88 76 87 77 / 70 50 90 50 N Ft Lauderdale 88 77 88 76 / 70 50 90 50 Pembroke Pines 88 76 87 75 / 70 50 90 50 West Palm Beach 88 76 88 75 / 80 40 80 20 Boca Raton 88 76 88 75 / 70 50 80 40 Naples 88 76 88 75 / 70 60 70 40

MFL WATCHES/WARNINGS/ADVISORIES

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