textproduct: Miami - South Florida

KEY MESSAGES

Updated at 219 AM EDT Tue Jun 30 2026

- Moderate to Major HeatRisk impacts will occur again today with peak heat index values ranging between 105 and 110 degrees across most areas.

- Chances of showers and thunderstorms will increase area wide heading into the middle of the week as a frontal boundary stalls out to the north.

- A return to more of a typical summertime pattern is anticipated this weekend as high pressure builds in from the western Atlantic.

SHORT TERM

(Today through Wednesday) Issued at 219 AM EDT Tue Jun 30 2026

A large and expansive ridge will remain centered off to the north across the Southeastern portion of the country as well as the Mid- Atlantic States today and this ridge will continue to slowly build eastward on Wednesday. At the same time, a weakness will develop along the southeastern side of the ridge over the western Atlantic as well as the Northern Florida and Georgia coastline. This will allow for weak vorticity impulses to sneak under the ridge and into Northern and Central Florida today, and then eventually closer to South Florida heading into Wednesday. At the surface, high pressure will begin to weaken as a frontal boundary pushes into Northern and Central Florida today before eventually stalling out on Wednesday across Central Florida. Out ahead of this front, winds will remain rather light and sea breeze driven each day. The biggest change in the weather pattern across South Florida will be that deep layer moisture advection will be taking place out ahead of the front as the Saharan Dust Layer gradually thins out today and then even more so on Wednesday. This will gradually cause PWATs to rise throughout today and Wednesday, generally ranging from 1.7 to around 2.0 inches this afternoon, and then up to 2.1 to 2.3 inches on Wednesday as the frontal boundary pushes closer to the region.

With deep layer moisture increasing across the area, convection chances will also gradually increase today, and even more so on Wednesday. Shower and thunderstorm activity will continue to be mainly sea breeze driven, however, the weakening frontal boundary to the north could provide an extra source of lift heading into Wednesday. While the highest chances of showers and thunderstorms looks to remain over the interior and Southwest Florida this afternoon, coverage looks to increase area wide on Wednesday as the frontal boundary gets closer to the region. As the steering flow will remain light through the middle of the week, convection will be slow moving and will be capable of producing heavy downpours with high rainfall rates. This could create the potential for localized flooding especially over portions of the metro areas as well as the poor drainage areas.

Heat will continue to be a concern for today and Wednesday as peak heat index values will generally range between 105 and 110 across most areas. This type of heat will create a moderate to major HeatRisk especially across the east coast metro areas as well as portions of Southwest Florida which will impact anyone without adequate cooling and proper hydration. While these conditions will be close to Heat Advisory criteria, probabilities remain on the lower side that the heat index will stay at these values for an extended period of time. Therefore, we will continue to monitor trends as the morning progresses.

LONG TERM

(Wednesday night through Monday) Issued at 219 AM EDT Tue Jun 30 2026

Heading into Thursday and Friday, the strong mid level ridge slowly pushes eastward and centers over the Mid-Atlantic States as well as the Carolinas by Friday. A weakness in this ridge remains in place on the southern side as another mid level shortwave impulse tries to push in from the Atlantic into Northern Florida and Southeastern Georgia. At the surface, what is left of the stalled out frontal boundary over Central Florida basically washes out, however, deep layer moisture will continue to pool over South Florida on Thursday. This will allow for the higher end chances of slow moving showers and thunderstorms to remain in place throughout Thursday. Multiple rounds of heavy downpours could lead to localized flooding especially over the metro areas once again on Thursday afternoon. As the end of the week approaches, the pattern will gradually start to shift back to more of a typical summertime pattern as surface high pressure in the western Atlantic begins to shift back towards South Florida. As the high builds back in from the western Atlantic, this will allow for the synoptic wind flow to gradually increase out of the southeast especially heading into Friday. This will also allow for the east coast sea breeze to push further inland, and focus afternoon convection over the interior and west coast during this time frame. Heat will continue to be a concern on both Thursday and Friday as well with high temperatures rising into the lower 90s. Peak heat index values will still range between 105 and 110 each day during this time frame.

Moving into the upcoming weekend, mid level ridging will gradually center over the western Atlantic and the western periphery of that ridge will build into South Florida as the weekend progresses. At the surface, South Florida will remain on the western side of an area of high pressure centered in the western Atlantic during this time frame. This will allow for a light to moderate southeasterly synoptic wind flow to set up across the region. The sea breezes will be the main driver of convective initiation each day and the highest chances of showers and storms will focus over the interior and west coast each afternoon where the sea breezes and other mesoscale boundaries collide. High temperatures over the upcoming weekend will generally rise into the lower 90s across most of the region. Peak heat index values will generally range from 103 to 108 on both Saturday and Sunday.

AVIATION

(06Z TAFS) Issued at 219 AM EDT Tue Jun 30 2026

Mainly VFR conditions will prevail throughout the forecast period. Light winds early this morning will increase out of the ESE after 16z and will remain around 10 kts through the afternoon. Scattered showers and storms will develop near the east coast terminals during the mid afternoon before pushing towards the interior and west coast. At KAPF, winds will increase out of the WNW after 17z. Periods of MVFR or IFR will be possible at KAPF during the late afternoon and early evening hours.

MARINE

Issued at 219 AM EDT Tue Jun 30 2026

Across the Atlantic waters, winds will remain rather gentle and variable through the middle of the week. Across the Gulf waters, a gentle to moderate northwesterly breeze will develop this afternoon before shifting and becoming east northeasterly tonight. Seas across the Atlantic and Gulf waters will remain at 2 feet or less through the middle of the week. Scattered showers and thunderstorms will develop across the local waters each day through the rest of the week. However, showers and storms may become more numerous towards the middle of the week as a frontal boundary stalls to the north of the region.

PRELIMINARY POINT TEMPS/POPS

Miami 94 79 92 78 / 30 10 80 50 West Kendall 95 76 93 75 / 40 20 80 50 Opa-Locka 96 79 93 78 / 30 20 80 40 Homestead 94 78 92 78 / 30 20 70 40 Fort Lauderdale 93 79 91 79 / 20 20 70 40 N Ft Lauderdale 93 79 91 78 / 30 20 70 40 Pembroke Pines 97 80 95 80 / 30 20 70 40 West Palm Beach 93 78 91 78 / 30 20 60 30 Boca Raton 92 79 90 78 / 30 20 60 40 Naples 93 77 92 77 / 40 30 60 40

MFL WATCHES/WARNINGS/ADVISORIES

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