Area Forecast Discussion

KEY MESSAGES

Updated at 703 PM EDT Tue Jul 21 2026

- Tropical Storm Bertha will begin moving further west today while drier air filters into South Florida from the southeast. Therefore, drier-than-normal weather is expected for the next couple days.

- Scattered showers and a couple isolated thunderstorms will focus across interior portions of the region today and tomorrow.

SHORT TERM

(Today through Wednesday) Issued at 202 AM EDT Tue Jul 21 2026

A more tranquil setup looks to be taking shape for the mid-week period as Tropical Storm Bertha begins to shift more westward today. In conjunction with it's westward propagation will be the expansion of surface high pressure over South Florida from the western Atlantic. Additionally, a drier than average air mass will begin to filter in as PWATs across South Florida fall to a general range of 1.2-1.4" and in some areas could be as low as 1.0-1.1". These values are near the lowest on record for this time of year and overall are below the 10th percentile. With this drier air and subsidence provided by expanding surface high pressure, any convection is expected to be primarily sea breeze driven and shallow in terms of cloud top heights. The highest PoPs under this pattern through mid- week will be over interior portions of the region at around 40-50%, while areas closer to the coastlines sit around 10-20%.

High temperatures today and tomorrow will reach the low to mid 90s for most areas and upper 90s for portions of the interior. Because of the drier air arriving, no Heat Advisory has been issued due to this drier air helping to lower dew points and relative humidity by a few degrees. This is expected to result in the region avoiding reaching Heat Advisory criteria through Wednesday.

LONG TERM

(Wednesday night through Monday) Issued at 202 AM EDT Tue Jul 21 2026

A strong ridge pattern across the western US will continue to expand across to even the southeastern US while surface high pressure remains parked over the Florida Peninsula. This pattern will prevent troughing across most of the Eastern Seaboard from pushing further south, which is expected to keep the local weather much quieter than normal through Thursday.

As we move into Friday, a westward moving upper-level trough is expected to advect across Cuba and parts of the Florida Straits for Friday and into the weekend. Long range guidance seems to be better aligned at this point with expecting this trough to avoid strengthening into a tropical system. Ensembles do not highlight this feature forming any low level circulation, giving increased confidence that the only real impact will be increasing rain chances as deeper moisture returns to the region for Friday and beyond into the end of the forecast period. Enhanced troughing across the Eastern Seaboard is also being hinted at for the end of the period on Sunday through early next week, with some positive vorticity advection potentially reaching South Florida and providing extra convection support in addition to the daily sea breeze circulations. However, high uncertainty exists given this is near the end of the forecast period.

High temperatures each day will continue to reach the low to mid 90s. Overnight lows will range from the low 70s for interior South Florida to the upper 70s and low 80s near the Gulf and Atlantic coasts. Potential for Heat Advisories will increase again late this week and into the weekend as elevated moisture returns to the area that could create enough of a humidity rise to necessitate excessive heat products.

AVIATION

(00Z TAFS) Issued at 703 PM EDT Tue Jul 21 2026

SCT showers possible near APF to start the 00Z TAF period, with VFR conditions over the east coast metro. Scattered showers possible along the east coast metro after 10Z with most activity pushing inland by the afternoon. Light and variable winds overnight, becoming SE 10-15 kts during the afternoon with a westerly Gulf breeze at APF.

MARINE

Issued at 202 AM EDT Tue Jul 21 2026

A moderate to fresh south-southeasterly wind flow will remain in place across the local waters through mid-week. These winds could maintain hazardous levels across the Gulf waters through late this morning before subsiding. Seas across the Gulf waters will range from 2 to 4 feet with the Atlantic at 2 feet or less. Scattered showers and thunderstorms will be possible across all local waters each day.

BEACHES

Issued at 202 AM EDT Tue Jul 21 2026

A moderate risk for rip currents continues for the Collier beaches today as a disturbance in the Gulf results in increased winds across the area. This risk may last through Wednesday across the Collier beaches before dropping off. Similarly, a moderate risk also continues for the Palm beaches today.

PRELIMINARY POINT TEMPS/POPS

MFL WATCHES / WARNINGS / ADVISORIES

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