textproduct: Miami - South Florida

KEY MESSAGES

Updated at 653 PM EDT Wed Sep 23 2026

- Scattered to numerous showers and thunderstorms expected again today. Rain chances remain elevated through Friday before falling this weekend. - Heavy downpours from the stronger showers and thunderstorms could lead to localized flooding over the urban and poor drainage areas each day.

UPDATE

Issued at 517 PM EDT Wed Sep 23 2026

A rather complex mesoscale environment has evolved across South Florida today. The combination of a mid-level impulse east of the peninsula and a surface disturbance over the Keys supported numerous showers and storms through the early morning hours over the east coast metros, particularly across Miami-Dade and Broward. Southerly flow aloft pushed the associated upper-level cloud cover northward, resulting in generally overcast conditions and limiting daytime heating across most of the South Florida peninsula. This effectively suppressed any subsequent convective activity across most of our region through this afternoon, with the bulk of the activity associated with the low/mid-level disturbance remaining south/east of the peninsula and over the adjacent Atlantic waters. A few showers and storms have pushed through the Lake region and SW Florida this afternoon, but overall activity is expected to continue to diminish overnight. A weak frontal boundary approaching from the north is expected to reach the Lake region by tomorrow morning. There remains some uncertainty regarding the exact timing of this frontal passage over our region, but most guidance indicates that the front will have moved through the peninsula by Friday. Shower and thunderstorm coverage tomorrow will largely depend on how quickly drier air behind the front is able to filter into our region. Current PoPs for tomorrow are generally at around 30-40%, favoring the eastern half of the peninsula under prevailing northwesterly flow. Low temperatures tonight will range from the mid-to-upper 70s along the coasts to the low 70s over the interior.

SHORT TERM

(Today through Thursday) Issued at 122 AM EDT Wed Sep 23 2026

The actively wet pattern is expected to last for another day before we start to see some drier air approach the area. Latest upper level analysis depicts South Florida sitting on the downstream side of an upper level shortwave trough located over the Gulf. This upper level shortwave is expected to provide some increased jet stream dynamics and pulses of positive vorticity advection that will be favorable for the development of more scattered to numerous showers and thunderstorms today. This is also supported by continual southerly low level flow, causing more deep moisture advection to occur. 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 remain above 2.1- 2.4 inches, which is above the 90th percentile for this time of year. This amount of moisture will make it easier for any level of forcing to produce scattered to numerous showers and storms.

With all of the aforementioned information above, there will once again be a risk for localized urban and poor drainage flooding today across the east coast metro areas due to plentiful antecedent rainfall the last couple of days. The current 3-hour flash flood guidance currently sits between 2-4 inches of rain across Southeast Florida, which can be achieved rather quickly as we have often seen here. Therefore, while not a widespread risk, there remains an outside chance for localized flooding today across the east coast metro areas. The Weather Prediction Center is carrying a marginal risk for excessive rainfall again today.

As we move into Thursday, we will start to see a pattern change as the upper level shortwave advects into an amplifying low off the New England and Mid-Atlantic coasts. With this entire troughing pattern shifting offshore, low level flow across South Florida will shift to a north to northeasterly direction and a frontal boundary will start approaching from the southern end of the trough base. Additionally, an upper level ridge will spill across the Southeast US. In return, this upper level high pressure influence and drier air filtering in is expected to cause a decrease in PoPs for Thursday, especially near the lake region where PWATs fall back somewhat closer to average (~1.7-1.9 inches). Thus, PoPs fall to 30- 50% across the lake region and most of Southwest Florida while remaining 60-70% across Southeast Florida. With less widespread rain likely on Thursday and a high pressure influence, not expecting localized flooding to be a concern for Thursday.

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

(Thursday night through Tuesday) Issued at 122 AM EDT Wed Sep 23 2026

For the end of the week and through this weekend, a frontal boundary will push southwards in tandem with the upper level trough strengthening off the Atlantic coast 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, with some of it expected to push into portions of our region, mainly the lake region. Near the lake and perhaps parts of northern Broward/Hendry, PWATs have potential to fall to 1.2-1.4 inches, which would be well below average. For far southern Florida, these values could still fall to 1.6-1.8 inches, which is around average for this time of year. With this anticipation of less moisture available and a thicker dry layer in the mid levels identified on model soundings, shower and thunderstorm coverage is expected to decrease for all areas. Lowest PoPs are forecast for the lake region where the driest air will be located, with higher PoPs further south. This is reflected with PoPs under 10-20% this weekend near the lake and 30-50% for the southern half of the forecast area. Dew points are projected to fall into the upper 60s for most areas across the region with this frontal passage this weekend, but it will still feel rather muggy outside.

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

AVIATION

(00Z TAFS) Issued at 653 PM EDT Wed Sep 23 2026

E/NE flow will persist until around 1Z-2Z where winds will transition to light and variable across all TAF sites. The frontal boundary pushing into the region tomorrow will bring lower ceilings along with uncertainty concerning the wind to primarily be out of the NNE or the NNW, especially into the early afternoon for all TAF sites. Low confidence on storm/shower development has resulted in a tentative VCSH introduction across the eastern terminals at 18z. Winds will return to light and variable for all TAF sites Thursday evening.

MARINE

Issued at 122 AM EDT Wed Sep 23 2026

A gentle southerly flow is expected across the local waters again today. These winds will then shift out of the north for the end of the week, primarily out of the northeast. However, a brief period of northwesterly winds is possible across the Atlantic late this week. Scattered showers and thunderstorms will continue to develop each day, producing locally hazardous winds and seas.

PRELIMINARY POINT TEMPS/POPS

Miami 76 89 76 88 / 30 40 20 50 West Kendall 75 89 75 89 / 20 40 20 50 Opa-Locka 76 89 75 89 / 30 40 20 40 Homestead 75 90 74 89 / 30 40 20 60 Fort Lauderdale 76 88 75 88 / 40 40 20 30 N Ft Lauderdale 76 89 76 88 / 30 40 10 30 Pembroke Pines 75 88 75 88 / 30 40 20 40 West Palm Beach 76 89 76 87 / 20 40 20 20 Boca Raton 75 88 75 87 / 30 40 20 20 Naples 74 90 73 89 / 20 20 20 0

MFL WATCHES/WARNINGS/ADVISORIES

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