textproduct: Miami - South Florida

KEY MESSAGES

Updated at 704 AM EDT Fri May 1 2026 - Patches of dense fog will be possible across inland southwestern Florida through daybreak this morning.

- Dry conditions will prevail with unseasonable heat possible this afternoon and Saturday. The odds of major (level 3 of 4) heat risk across the east coast metro on Saturday continues to increase.

- Rain chances increase during the second half of the upcoming weekend into early next week. Uncertainty remains high on the timing and coverage of showers and storms.

SHORT TERM

(Today through Saturday) Issued at 218 AM EDT Fri May 1 2026

06z Mesoanalysis continues to depict the centrum of surface high pressure just to the west of South Florida across the southeastern Gulf this morning. ACARS data from local airports in tandem with GOES East derived TOWR soundings depict the development of a shallow near surface nocturnal inversion across most inland areas. Above this stout surface inversion and below a higher subsidence inversion in the vertical column at 750mb, enough atmospheric moisture remains at roughly 4,000-5,000 feet for the continuation of a deck of stratus overnight, mainly across the eastern half of the region. Brisk moving cirrus rounds out the top of the vertical column as it moves across our area along the far southern periphery of a robust jetstreak across the southeastern United States. With surface ridging just to the west of our area, winds have decoupled across inland locales, especially across inland southwestern Florida. With less cloud cover present across the western half of the peninsula overnight, radiational cooling and the near surface inversion will allow for efficient radiational cooling and the potential development of patches of dense fog across inland Collier, Hendry, and Glades counties. Recent HREF model guidance depicts a medium (40- 60%) probability of visibility dropping below 0.25 miles across these areas through 9am this morning. REFS model guidance is also in agreement with the same probabilistic values. Inland routes such as US-29, Collier Blvd, Alligator Alley, and Tamiami Trail could see reduced visibilities during this time frame and motorists are advised to exercise caution if encountering fog.

Our weather regime today will once again be dictated by surface features in our vicinity and mesoscale diurnal processes. A stalled frontal boundary across northern Florida will remain in place as the axis of weak surface ridging remains in place across the southeastern Gulf. Anticyclonic flow around this surface high to our southwest will result in background wind flow out of a light southwesterly direction today. This setup at the surface combined with residual dry air and subsidence aloft will set the stage for above average temperatures this afternoon across South Florida (with the exception of coastal communities along the immediate Gulf coast). A pinned Atlantic sea-breeze will result in high temperatures across the east coast metro reaching the upper 80s to low 90s this afternoon as temperatures inland (Lake Okeechobee and the Everglades) could even reach the mid 90s. The NBM 90th Percentile (1 in 10 Chance) even highlights a non zero chance of some upper 90s possible across inland South Florida this afternoon. Normal high temperatures for this time of year are in the low to mid 80s. According to the NWS Prototype Probabilistic Heat Risk, there is a 70-90% probability of a Moderate (Level 2 of 4) Heat Risk across most of the region this afternoon. Individuals who are sensitive to heat should ensure access to hydration and cooling while limiting prolonged outdoor exposure.

An active synoptic evolution will continue during the rest of today into tonight across much of the continental United States as transient lobes of mid-level vorticity advect briskly along in a combined southern and polar jet-stream. To our southwest, an expansive mid-level ridge will continue to flatten while sliding eastward across the far southern Gulf today. In between the active jet & troughing to our north and the mid-level ridge to our south, 500mb flow across South Florida will veer from a northwesterly direction today to a westerly than southwesterly direction overnight into early Saturday. Our attention will primarily remain on the evolution of an amplified subtropical trough sliding eastward across Texas. Although the aforementioned subtropical shortwave will lose amplification & definition on Saturday morning as the next long-wave trough axis slides southward across the Great Lakes, the infusion of synoptic energy across the region will aide and kick-off the propagation of the surface frontal boundary previously stalled out over the northern Gulf and Florida eastward on Saturday. The right entrance region of a stout jet-streak around the base of the trough will facilitate the development of an initial area of low pressure in the Gulf before a more pronounced area of surface vorticity develops and deepens offshore of North/South Carolina.

As the low pressure systems develop and the frontal boundary slides closer to the region, South Florida will be present in the heart of the warm sector, setting the stage for what could potentially be the hottest day of 2026 for South Florida thus far. Warm air advection will be amplified as a low level jet enhances out of the south to southwest. The combination of the moisture surge, breezy southerly to southwesterly flow, and a lack of cloud cover will set the stage for widespread low to mid 90s across the east coast metro areas and into the mid 90s across the interior sections. It's worth noting that the NBM 75th percentile which performs well in these type of flow regimes has trended higher, with potential values in the upper 90s not out of the cards for western suburbs of the east coast metro. Apparent temperatures (heat indices) will also surge higher due to the introduction of higher atmospheric moisture into the region, with a duration of values in the low 100s possible for several hours on Saturday afternoon. According to the NWS Prototype Probabilistic Heat Risk, there is a 60-80% probability of Major (Level 3 of 4) Heat Risk for much of the east coast metro on Saturday where as a Moderate Heat Risk (Level 2 of 4) will be realized across the remainder of the region. Unseasonable heat for this time of year could affect anyone without cooling/hydration as well as health systems and industries.

LONG TERM

(Saturday night through Thursday) Issued at 218 AM EDT Fri May 1 2026

After unseasonable and near record heat possible across portions of South Florida on Saturday, the second half of the weekend is forecast to be more convectively active as the frontal boundary arrives at our doorstep. Zooming back into the forecast via a synoptic lens, the surface low offshore of the Carolina coast will continue to deepen as it accelerates to the northeast into the northern Atlantic in tandem with the axis of the longwave trough sliding eastward across the Great Lakes. This will result in the continued propagation of the frontal boundary southward across the Florida Peninsula Saturday night into Sunday. While deterministic and ensemble models have come into better agreement over the past 24 hours, differences do remain from model suite to model suite even at this hour.

Much of the forecast uncertainty (as discussed in various discussions over the past 48 hours) falls on the exact timing and evolution of the frontal boundary across our region. A quicker and earlier arrival of the frontal boundary into and across the region would limit any destabilization ahead of the boundary which would preclude any threat of more robust storms or threat of heavier rainfall. Conversely, a slower propagation and arrival could provide enough time for destabilization to occur and for more robust convection to fire in the vicinity of the boundary and a higher concern for an localized urban flooding threat. QPF clusters as well as ensemble guidance continue to depict widespread rainfall totals remaining in the 1-2" range, with the highest values forecast over the east coast metro. Some localized totals could be slightly higher where boundary collisions and back-building occurs. The Weather Prediction Center has maintained a marginal risk (level 1 of 4) of excessive rainfall across the eastern half of the region on Sunday. Deterministic and ensemble models are great for diagnosing the overall synoptic setup but often have spatial and temporal limitations on the metaphysics of convective evolution. Luckily, we are almost at the window of time where our more reliable deterministic (HRRR, RAP, etc) and ensemble (HREF, REFS, etc) mesoscale models can help us better diagnose the setup. The evolution of the front over the next 48 hours will give us better insight into which solution will be more likely to occur. Be sure to stay tuned to the forecast over the next 48 hours as details become more clear.

As the the mid-level trough advects into the western Atlantic during the day on Monday, the frontal boundary will stall just to our south over the Florida Keys and Florida Straits. Rain chances will decrease during this period but remain in the 30-40% range across the region as a temperature gradient is forecast during the afternoon hours (low 80s across the northeastern portion of the region, upper 80s across coastal southwestern Florida). The axis of mid-level troughing will continue into the western Atlantic on Monday night as 500mb flow across the region veers back to a northwesterly component.

A developing mid-level ridge across the Gulf and southern United States will slide eastward into the region during the mid-week period bringing a return to well above average temperatures and low rain chances during the mid-week period. Widespread high temperatures in the low to mid 90s are possible during this period.

AVIATION

(12Z TAFS) Issued at 704 AM EDT Fri May 1 2026

Light winds will veer out of a southwesterly direction over the next couple of hours before winds veer onshore out of a southeasterly direction along the east coast by 17-19z. VFR and dry conditions are expected for the remainder of the TAF period outside of any patchy inland fog across inland SW Florida this morning.

MARINE

Issued at 218 AM EDT Fri May 1 2026

Light and variable winds across all local waters at daybreak will veer to a southwesterly direction across the Gulf waters and out of a southerly to southeasterly direction across the nearshore Atlantic waters by the early afternoon hours. An afternoon wind surge could once again result in a brief duration of small craft exercise caution conditions (SCEC) across the northern Atlantic waters. Winds will begin to enhance tonight as a frontal boundary moves southward across the northern Gulf, resulting in SCEC conditions once again across the Atlantic waters on Saturday with even some potential of a brief duration of conditions hazardous to small craft across the northern Atlantic zones. Seas across the Atlantic waters will generally range from 2 to 4 feet through the first half of the weekend while seas across the Gulf waters remain at 2 feet or less. The arrival of a frontal boundary in the vicinity of South Florida during the second half of the weekend into next week could result in scattered to numerous showers and storms across the local waters which could bring locally hazardous winds and waves during that time frame. Northeasterly swell behind the frontal boundary early next week could result in higher wave heights across the Gulfstream waters during that time frame.

BEACHES

Issued at 218 AM EDT Fri May 1 2026

Due to a lingering northeasterly swell, a high risk of rip currents will persist across the Palm Beaches for the first half of the weekend. A moderate risk of rip currents will remain in place across the rest of the Atlantic Coast beaches during this time frame

FIRE WEATHER

Issued at 218 AM EDT Fri May 1 2026

A nocturnal inversion present across the majority of inland South Florida at daybreak will erode over the remainder of the morning hours as winds gradually enhance out of westerly to southwesterly direction. While wind speeds will remain relatively light, enhanced fire behavior remains possible this afternoon as a combination of dry fuels (Fire Potential Forecast of 4) and relative humidity values (mid 30s to low 40s) near critical thresholds is forecast for inland locations once again. Closer to the coast, onshore winds will moderate the airmass slightly precluding lower relative humidity values. Winds will enhance and become breezy to gusty on Saturday, especially during the afternoon hours which may once again facilitate enhanced fire behavior on Saturday afternoon. With the frontal boundary arriving across the region on Sunday, moisture return and precipitation will act to bring increased moisture back into the region.

CLIMATE

Issued at 218 AM EDT Fri May 1 2026

Today's Forecasted High Temperature Values: Miami (KMIA): 89 Fort Lauderdale (KFLL): 88 West Palm Beach(KPBI): 88

Today's 90th Percentile High Temperature Values: (1 in 10 Chance) Miami (KMIA): 92 Fort Lauderdale (KFLL): 91 West Palm Beach (KPBI): 91

Today's Record Maximum High Temperature Values: Miami (KMIA): 92 Fort Lauderdale (KFLL): 92 West Palm Beach (KPBI): 93

PRELIMINARY POINT TEMPS/POPS

Miami 89 75 92 76 / 0 0 0 30 West Kendall 92 71 94 72 / 0 0 0 30 Opa-Locka 91 74 94 75 / 0 0 0 30 Homestead 89 74 91 74 / 0 0 0 30 Fort Lauderdale 88 74 91 75 / 0 0 0 30 N Ft Lauderdale 88 74 92 74 / 0 0 0 30 Pembroke Pines 92 75 95 76 / 0 0 0 30 West Palm Beach 89 71 94 71 / 0 0 10 40 Boca Raton 88 73 92 73 / 0 0 10 40 Naples 86 72 87 72 / 0 0 0 60

MFL WATCHES/WARNINGS/ADVISORIES

FL...High Rip Current Risk through Saturday evening for FLZ168.

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