textproduct: Miami - South Florida

KEY MESSAGES

Updated at 708 PM EDT Wed Oct 21 2026

- Hazardous marine conditions continue tonight for both the Atlantic and Gulf waters.

- High risk of rip currents continues for the Atlantic beaches, and will likely last at least into early next week. In addition, high surf conditions continue for the Palm Beaches.

- Moderate coastal flooding is expected to continue around high tide along the east coast. A low, 10-30% chance of major coastal flooding is possible beginning during the second half of the upcoming weekend.

- Heavy rain, isolated flash flooding, and windy conditions are forecast for this weekend into early next week.

UPDATE

Issued at 410 PM EDT Wed Oct 21 2026

The forecast remains generally on track this afternoon. We continue to monitor the potential for heavy rainfall this weekend, in conjunction with a likely very impactful King Tide coastal flooding event. In this update, we will highlight any notable revisions to the short term and long term forecasts.

Through the short term period (today and tomorrow), our area will remain under an area of high pressure and subsidence with PWATs running below the 10th percentile for this time of year. This will continue to result in negligible sensible weather impacts across the region, with PoPs across much of the region below 15% and temperatures in the mid 80s each day. Breezy conditions will persist and could be gusty at times. Coastal flooding today and tomorrow could overperform previous forecast levels, with Moderate coastal flooding possible along the East Coast. We upgraded the Coastal Statement up to an Advisory, and those conditions will likely persist through at least Thursday, potentially worsening later into the weekend as we reach the peak of the King Tide cycle.

Once we get into the long term period (Friday onwards), there is increasing confidence that we will be seeing a heavy rainfall event across portions of South Florida between Friday-Sunday night. That being said, the remaining uncertainty comes from a discrepancy between ensemble members regarding where the potential surface low develops and interacts with the surface high shifting over the southeast US. This interaction will promote convergence and strong northeasterly flow that could drive repeated rounds of rainfall across the area. The further north and/or east that this interaction sets up, the lower the rainfall amounts for our area, but any shift west or south could lead to the higher-end rainfall values discussed in last night's Long Term discussion. This, combined with aforementioned King Tide coastal flooding event and hazardous marine and surf conditions, could exacerbate flooding concerns along the coast.

SHORT TERM

(Today through Thursday) Issued at 100 AM EDT Wed Oct 21 2026

Surface high pressure will remain to our north today and Thursday. At the upper levels, height falls will continue as a trough builds across the state and the ridge over the middle of the country starts to nose eastward. Mainly dry conditions are expected the next couple of days, with plenty of dry air in the mid and upper levels of the atmosphere. Just enough low level moisture will be in place for occasional coastal showers across the east coast metro, especially during the evening and overnight hours.

High temps today and Thursday will be in the low to middle 80s for most, with some upper 80s over SW FL. Low temps tonight will range from the middle 60s around the lake to the lower 70s near the Atlantic coast.

LONG TERM

(Thursday night through Tuesday) Issued at 208 AM EDT Wed Oct 21 2026

Forecast gets interesting as we head into the weekend and into early next week. A 500 mb low will form in the vicinity of Cuba and strong surface high pressure will be in place over the northeast US. Deep moisture will be in place over SE FL for multiple days with PWAT values increasing to 1.8-2.0 inches. Rounds of heavy rainfall appear likely especially on Saturday and Sunday, but may continue into Monday as well. Mean rainfall totals from Friday through Monday show 3-6 inches for the east coast metro, with worst case scenario values over 10 inches possible. Given the peak of the current king tide cycle is also this weekend, the potential exists for some serious flooding concerns across the metro and other poor drainage locations along the coast. Should the forecast remain the same over the coming days, Flood headlines would be very likely.

In addition to the heavy rain threat, the tightening of the pressure gradient this weekend across FL will result in breezy NE winds, with gusts of 30-40 mph likely, especially along the coast.

Conditions will improve for Tuesday into mid week as the upper low opens up and lifts up to the northeast and drier air moves back into the area.

Temperatures during the extended period will see high temps in the low to mid 80s each day and lows in the 60s/70s.

AVIATION

(00Z TAFS) Issued at 708 PM EDT Wed Oct 21 2026

Light northerly flow overnight with isolated SHRA possible at times, primarily at east coast terminals. Breezy north- northeasterly flow after daybreak tomorrow with the continued potential of isolated SHRA. Higher wind gusts (20-25 knots) could be realized in and around SHRA activity.

MARINE

Issued at 100 AM EDT Wed Oct 21 2026

Hazardous seas will continue in the Atlantic waters the rest of the week with seas of 6-9 ft. NE winds 15-20 kts. In the Gulf waters, hazardous winds early in the day will become cautionary by this evening.

Hazardous winds and seas return for all local waters this weekend into early next week as the pressure gradient tightens across the area. Gale force winds are possible in both the Atlantic and Gulf waters this weekend.

BEACHES

Issued at 100 AM EDT Wed Oct 21 2026

A high risk of rip currents will remain for the Atlantic beaches through early next week. In addition, dangerous waves of 6-10 ft in the surf zone are likely in the Palm Beaches through early next week.

HYDROLOGY

Issued at 410 PM EDT Wed Oct 21 2026

We're beginning to come out of an ebb in the astronomical tides as we head towards the full moon and peak of the tide forecasts late this weekend and into early next week. Observed water-levels are already over-performing predictions and we'll likely begin reaching Moderate flooding thresholds this evening at all of our east coast tidal stations. It's also not out of the question that Palm Beach county may even reach Major flooding levels at the peak of the King Tide.

The normal King Tides are complicated by the fact that we'll be dealing with a complex upper/surface low pressure pattern that will feature an approaching front from the north and convection rising out of the Caribbean from the south. This will likely increase the onshore wind component and magnify the already high tides. This is somewhat accounted for in the predictions mentioned above, but only crudely. Furthermore, the potential for heavy rainfall during periods of high tide is also something to be aware of that could further aggravate coastal flooding. In short, we're heading into what could be a rather impactful period for coastal flooding and sensitive locations should consider preparations.

PRELIMINARY POINT TEMPS/POPS

Miami 71 83 71 82 / 10 30 30 50 West Kendall 70 84 70 84 / 0 20 20 50 Opa-Locka 70 83 70 83 / 10 30 30 40 Homestead 70 84 70 83 / 0 20 40 50 Fort Lauderdale 71 82 71 82 / 20 30 40 50 N Ft Lauderdale 72 83 71 82 / 20 30 30 40 Pembroke Pines 70 83 70 83 / 10 30 30 40 West Palm Beach 71 82 71 82 / 30 20 30 30 Boca Raton 71 82 71 82 / 20 30 40 40 Naples 67 83 66 84 / 0 0 0 0

MFL WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Advisory until 11 PM EDT Thursday for FLZ168-172- 173.

High Rip Current Risk through Friday evening for FLZ168-172-173.

High Surf Advisory until 8 PM EDT Friday for FLZ168.

AM...Small Craft Advisory until 8 PM EDT Friday for AMZ650-651-670- 671.

GM...Small Craft Advisory until 8 PM EDT this evening for GMZ656-657- 676.