textproduct: Miami - South Florida

KEY MESSAGES

Updated at 133 PM EDT Mon Jul 6 2026

- Scattered to numerous thunderstorms expected this afternoon through early evening. In addition to frequent lightning, heavy downpours and isolated 50 mph wind gusts are the main threats.

- A moderate to major HeatRisk is expected again today, with peak Heat Index values ranging from around 103 to 108F. The heat will continue to build through at least midweek. Wear light- weight, light color clothing and stay hydrated.

SHORT TERM

(Today through Tuesday) Issued at 210 AM EDT Mon Jul 6 2026

The recent 00z MFL sounding indicates that the airmass over South Florida this evening is still quite moist and unstable. PWATs are hovering at around 2.1 inches and MLCAPE is still between 1500 to 2000 J/kg. As a result, isolated showers are still lingering across South Florida, with new development mainly over the more unstable Gulf Stream waters and FLorida Straits. Most activity should wane, but some light showers be observed through the early morning hours over the metro. Similar to the last few days, the majority of diurnal thunderstorm activity will focus along sea-breeze and outflow boundary interactions during the afternoon and evening. As mentioned in the previous discussion, some of the 00z CAMs continue to show a signal for an early start for convection. As the Atlantic sea breeze pushes inland, thunderstorms could begin developing across the Dade, and Broward metro areas before noon. The highest chances of precipitation then look to focus over interior portions of South Florida during the middle and latter half of the day.

Mid-level ridging will continue to build over the next few days, with the main ridge axis centering itself just off shore over the Bahamas for this afternoon. Guidance indicates that 500 mb heights may climb into the 591-593 dam range, which would be within the 75th percentile for this time of year. At the surface, the more dominant high pressure center will be over the Atlantic, but with it's positioning further east, the overall wind regime may shift a tad more southerly this afternoon. Other solutions show a stronger Gulf breeze, which would advance further inland and keep the Atlantic breeze pinned further east. This would allow for higher chances for storms over the Miami-Dade and Broward metro areas. In any case, steep low level lapse rates, 90th percentile PWATs, and plenty of instability should allow for heavy and efficient rainfall, frequent lightning, and gusty winds.

Heat will continue to be a concern over the next few days, with temperatures actually trending up through the middle of the week. Opted not to issue a Heat Advisory today, figuring that early convection and cloud cover may keep most areas over the metro from climbing over heat indices of 105 F and limiting the window of time for hottest conditions. However, would not be surprised if some isolated urban locations do see heat indices up to 108 F for a short time. There is still widespread Moderate HeatRisk across most of SoFlo, affecting sensitive individuals without proper hydration and cooling.

For Tuesday, high pressure looks to continue building over the region, leading to Moderate and Major HeatRisk. Once again, scattered to numerous storms will develop along sea breeze and mesoscale boundary interactions, with the highest chances over interior SoFlo. However, PWATs look to start trending down, so PoPs are a little bit lower than for Monday.

LONG TERM

(Tuesday night through Sunday) Issued at 210 AM EDT Mon Jul 6 2026

Global ensembles start the period with some positioning differences regarding the merging of shortwaves over the Pacific Northwest that will affect the downstream pattern by the weekend. Through at least the end of the week there's unanimous consensus on a mostly zonal northern stream pattern, with a filling shortwave across the MS/TN Valleys. The upstream differences will mainly influence the timing of the amplification of an eastern CONUS trough this upcoming weekend, be it Saturday or Sunday. For the immediate south Florida area, no deep-layer synoptic forcing from the northern stream is expected through the period.

The main mid/upper level feature of concern will be the building subtropical ridge. Both the NAEFS and ECMWF ensembles depict near record 500mb heights by Wednesday, with H5 and H7 heights remaining in the top 10th percentile of climatology for this time of year through the weekend. All of the raw European ensemble members exceed what the model typically forecasts for this time of year. An EFI of 80-90% and an analysis of the ensemble CDF indicates that many of the ensemble members are nearing the model climate extremes for this time of year as it relates to model forecasts. The NAEFS and ECMWF suite also is forecasting low-level moisture anomalies in the top 10th percentile related to climatology for this time of year. This all points towards above normal temperatures and humidity, which should substantially increase the risk for heat related illness from mid-to late week through the weekend. A prolonged period of heat advisory level apparent temperatures (107-110) are expected, with the probability of exceeding 110 degrees climbing from about 20% (mid week) to 50% by the weekend.

As far as thunderstorms are concerned, QPF ensemble cluster analysis does not depict any trackable areas of significant QPF through the period. Through the end of the week, storms will be primarily driven by the seabreezes. With steering flow mainly in the SE direction, expect nocturnal to morning showers along the Atlantic coast, with more robust convection across the interior and west coasts later in the day. The coverage of storms may be limited each day as a Saharan Air Layer (SAL) is forecast to advect through the Caribbean, western Atlantic, and the Florida peninsula. However, by the weekend, moisture and forcing may increase a bit as a TUTT is forecast to drift WSW through the southern Bahamas and northern Caribbean. While widespread significant rainfall is not expected, storms may be a bit more numerous than typical and not necessarily follow the typical seabreeze pattern.

AVIATION

(18Z TAFS) Issued at 136 PM EDT Mon Jul 6 2026

Thunderstorms or VCTS will be likely through most of this afternoon with chances decreasing after sunset. Wind direction will average SSE, though erratic winds are likely in thunderstorms. VFR conditions prevail outside of thunderstorms. Winds will become light and variable overnight but will return to SSE by mid to late morning tomorrow.

MARINE

Issued at 210 AM EDT Mon Jul 6 2026

High pressure will continue building over the region through the middle of the week. As a result, winds will remain light and out of the south to southeast over the Atlantic waters and south to southwest over the Gulf waters. Diurnal sea-breezes will shift winds more onshore during the afternoon and evening hours. For the middle of the week, winds look to shift more east to southeast for both the Atlantic and Gulf waters. Afternoon thunderstorms look to develop inland each afternoon, with activity then spilling out into the waters during the evening hours from boundary interactions. Light showers and isolated storms will stream across the open waters overnight and into the early morning. Locally higher seas and gusty winds will be the main concerns with any storm. Chances for showers and storms decrease during the middle to end of the week as some drier air filters into the region.

PRELIMINARY POINT TEMPS/POPS

Miami 79 90 79 93 / 20 50 10 10 West Kendall 76 90 77 93 / 20 50 10 10 Opa-Locka 78 91 79 94 / 20 50 10 10 Homestead 78 91 79 93 / 10 50 10 10 Fort Lauderdale 79 90 80 92 / 20 40 10 10 N Ft Lauderdale 78 90 79 92 / 20 50 10 10 Pembroke Pines 78 93 79 95 / 20 50 10 10 West Palm Beach 77 89 78 92 / 20 50 10 20 Boca Raton 79 90 79 91 / 10 50 10 10 Naples 77 90 77 94 / 20 50 20 40

MFL WATCHES/WARNINGS/ADVISORIES

FL...Heat Advisory until 7 PM EDT this evening for FLZ071>074-172>174.

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