textproduct: Miami - South Florida

KEY MESSAGES

Updated at 642 PM EDT Tue Aug 11 2026 - A Heat Advisory is in effect today for all of South Florida.

- Heat remains the primary hazard through next weekend.

- Greatest rain chances for all of south Florida on Thursday.

SYNOPSIS

Issued at 135 AM EDT Tue Aug 11 2026

Deep layer ridging will prevail across the Deep South and Florida over the next several days. The periodic amplification of the eastern CONUS trough will play a role in the position of the ridge axis which will have implications for low-level flow patterns and temperature forecasts.

Over the next few days, global ensembles generally agree that while the core of the northern stream will remain mostly north of the CONUS, weak shortwaves will advect southeast through the Plains and Midwest. These waves will result in a slight amplification to the eastern CONUS trough Wed. into Thurs. This will push the ridge axis from over Florida into the Gulf.

By the end of the week, the combination of a shortwave moving into the western CONUS and another moving through the Northeast will sharply amplify the ridge across then central and southern CONUS, including the Deep South and Florida. While there is quite a bit of disagreement in the ensembles regarding the timing and intensity of the Northeast shortwave, the general pattern across our region remains similar regardless.

SHORT TERM

(Rest of today through Wednesday) Issued at 209 PM EDT Tue Aug 11 2026

It's definitely hot across South Florida today, with Heat Advisories along the entire region this afternoon. At times it may feel like Icarus flying too close to the sun, and it may seem like a Herculean task to combat these dangerously hot conditions. However, there is no reason to be 'playing with fire' while spending time outdoors, as there are several simple solutions one can take to protect themselves from hot temperatures. Drink plenty of water, even if you don't feel thirsty, and use cool, damp towels on your skin to help regulate body temperature. The thought of a nice crisp beer may seem like a siren's song, but it is important to limit your intake of alcoholic, caffeinated, or sugary drinks while outdoors as they will lead to dehydration. Remember to wear loose, lightweight, and light- colored clothing. It may seem like a Sisyphean task to have to re- apply sunscreen every two hours, but protection from strong ultraviolet rays will make one less suceptible to heat related illness. Failing to take any heat safety precautions may open a pandora's box of issues down the line, increasing the risk of heat exhaustion and heat stroke. Confusion, dizziness, nausea, and weakness are all signs of heat stroke. If symptoms do not improve after moving to a cool area and sipping water, seek medical attention immediately.

Current observations indicate that heat indices across the region are between 105 and 110 F, creating widespread Major HeatRisk across all urban areas. The threat of vehicular heat stroke also hangs over like the Sword of Damocles. Never leave kids or pets unattended - LOOK before you LOCK! Temperatures inside vehicles can quickly become deadly, often climbing 30 degrees higher than the ambient outside temperature. Maximum forecast temperatures are expected to be in the low to mid 90s for most of the region, which is slightly above average for this time of year. These conditions are nothing too out of the ordinary for most Floridians, but heat is often the Achille's heel for many as it is the deadliest weather hazard in America according to the Centers for Disease Control and Prevention. Therefore, to drive the point home while not sounding like an echo chamber, remember to take frequent breaks, stay hydrated, and check in on friends and family during these extended heat events.

Outside of heat, isolated to scattered showers and storms will mainly focus along the Gulf breeze over interior and Southwest Florida. The 12z MFL sounding and recent ACARs observations from KMIA show a very pronounced dry layer between 850 mb and 300 mb, with PWATs near the 10th percentile for this time of year. Dry air and subsidence aloft should greatly limit chances of precipitation this afternoon, so there is no apple of discord among ensemble guidance for this afternoon's shower activity. Much of this drier air is attributed to Saharan dust, whose odyssey adventure has taken it from northern Africa all the way to the Gulf. Model soundings seem to indicate that some better moisture will make its way into the region on Wednesday, so PoPs have climbed into the 40 to 60% range areawide for Wednesday afternoon. Easterly flow will weaken slightly, so most storms will form along sea breeze and outflow boundary interactions over interior South Florida. The drier mid level air may actually act as a Trojan Horse in this wetter environment, and instead of limiting convection, it may actually enhance the potential for a few strong downdrafts (low confidence). Overall, the main threats will be frequent lightning, gusty winds, and locally heavy rainfall from a few isolated stronger cores.

LONG TERM

(Wednesday night through Monday) Issued at 135 AM EDT Tue Aug 11 2026

Thursday will probably be the 'coolest' and 'wettest' of the period as the ridge axis will be furthest west and will be awaiting the northern stream shortwave to begin the amplification of the ridge pattern. It'll still be hot, with highs generally in the middle 90s and heat indices nearing advisory levels, though there will probably be fewer upper 90 degree readings. With at least some component of northerly flow expected on Thursday, we'll likely see the breezes pinned closer to the coast. However, we'll also be more likely to see storms advect into the region from central Florida late in the day. Overall, coverage is expected to be highest on Thursday. The end of the week and into the weekend will feature the presence of the SAL once again and anomalous heights. Essentially another period of warmer and drier than normal conditions are expected.

AVIATION

(00Z TAFS) Issued at 642 PM EDT Tue Aug 11 2026

Storm activity will dissipate after sunset, with winds becoming light and variable. Winds will pick up out of the southeast tomorrow once again for all eastern sites, while a Gulf breeze will shift winds west at KAPF. Scattered storms expected to develop along interior South Florida. Only had enough confidence to include VCTS at KDJT, KFXE, and KTMB.

MARINE

Issued at 135 AM EDT Tue Aug 11 2026

Light winds and low seas are expected through the week. Daily wind increases to around 10 knots are expected in the seabreeze zone, as well as a light chop. Shower and thunderstorm activity will remain fairly isolated and mostly limited to the morning hours for the east coast and the evening for the Gulf.

PRELIMINARY POINT TEMPS/POPS

Miami 80 93 79 92 / 0 40 10 30 West Kendall 77 93 75 92 / 0 50 10 40 Opa-Locka 79 94 80 93 / 0 40 10 40 Homestead 78 93 78 92 / 0 40 10 30 Fort Lauderdale 79 92 80 91 / 0 40 10 30 N Ft Lauderdale 80 93 79 92 / 0 40 10 40 Pembroke Pines 80 93 79 92 / 0 40 10 40 West Palm Beach 78 94 78 93 / 0 60 10 50 Boca Raton 79 92 78 91 / 0 50 10 40 Naples 79 91 78 92 / 20 40 10 50

MFL WATCHES/WARNINGS/ADVISORIES

FL...Heat Advisory until 7 PM EDT this evening for FLZ063-066>075-168- 172>174.

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