Key Biscayne residents should prepare now: the first king tides of 2026 will push water onto the island's lowest streets starting Tuesday, Aug. 11.
The South Florida Water Management District released the full 2026 king tide schedule, with the first window running Aug. 11 through Aug. 14, according to the Miami Herald. The joint SFWMD and University of Miami weekly forecast does not call for serious flooding during this first window. High tides are expected to run about a foot above normal, below the threshold for "minor" flooding.
But on a barrier island where normal high tide already reaches about 2 feet at the NOAA Key Biscayne gauge, that extra foot matters. The Village of Key Biscayne's FEMA flood depth map shows most of the island sits in Zone AE or Zone VE, the highest-risk flood designations. Streets including Harbor Drive, W. Heather Drive, W. Matheson Drive, Mashta Drive and Cape Florida Drive all fall within the Special Flood Hazard Area.
Residents who lived through the September 2022 king tides remember what even moderate tidal flooding looks like here. Village officials confirmed at the time that storm drains were already overflowing by midday on Sept. 26, 2022, before Hurricane Ian's rain bands arrived.
Why king tides hit Key Biscayne hard
King tides occur when the sun, moon and Earth align to produce the year's highest tides. Some produce little more than an inch of saltwater pooling in a storm drain. Others, combined with onshore winds or heavy rain, can flood streets and overwhelm drainage systems.
Key Biscayne's vulnerability is structural. In a September 2024 CBS Miami segment on the village's $75 million Resilient Infrastructure and Adaptation Program, a village official described the stormwater system as "kind of a mixed mess" that "just is not adequate." That program targets Zone 1, the island's most flood-prone area.
In October 2025, the government sensor at Virginia Key set a new sea level record, 1.9 inches above the previous mark from 2023. Brian McNoldy, a meteorologist at the University of Miami's Rosenstiel School, told the Key Biscayne Independent in November 2025: "The new record jumped out at me."
Full 2026 king tide schedule
Per SFWMD, the predicted flooding windows are:
- Aug. 11–14
- Sept. 8–15
- Sept. 24–Oct. 15
- Oct. 22–Nov. 12
- Nov. 22–29
- Dec. 22–27
The worst flooding is expected near the Oct. 27 full moon.
What residents can do now
The Village of Key Biscayne maintains a flood preparedness page with guidance on protecting property. Residents can also check the SFWMD/University of Miami weekly forecast tool for updated predictions as each window approaches.
Miami-Dade County's Flood Zone Hotline, 305-372-6466, is available Monday through Friday, 8 a.m. to 5 p.m., for questions about flood zone designations and king tide events.
