textproduct: Key West

KEY MESSAGES

- Major coastal flooding in the Upper Keys and minor to moderate coastal flooding in the Lower to Middle Keys is ongoing, especially around high tide.

- Small Craft Advisory conditions are expected from today through early next week. Near-gale breezes will be possible at times Sunday evening through Monday evening, especially SE Gulf. - Little to no relief from significant coastal and marine impacts are expected into at least the middle of next week. Residents and visitors should take the necessary actions to protect flood- prone property.

DISCUSSION

Issued at 345 PM EDT Sat Oct 24 2026 The second to last weekend of October opened with mostly sunny skies across the Florida Keys. KBYX radar returns suggest that shower activity significantly diminished across the CWA after lines of showers and thunderstorms over the southwestern Straits of Florida. Breezes along the reef have waxed and waned from moderate to fresh and fresh to strong. In the meantime, satellite observations show a drier mass of air wrapping around into the Keys from Northern Florida. While lingering cloud cover in the upper atmosphere suggests a bit of moisture is present, advected layer PWAT from 850 to 700 mb highlights the dry slot over the Keys. Tonight, the main story for weather will revolve around winds and the tides. The king tide cycle is at its yearly peak, and unfortunately the flooding is on track to get worse before it improves. While a Coastal Flood Warning is not out for the Lower and Middle Keys yet, we may enter warning territory within the next few days.

A highly amplified weather pattern continues across North America. A cutoff low is moving into the Four Corners region, a second low is rapidly moving across western Canada, and a third trough continues to deepen towards Cuba just off the eastern coast. Between all these upper level lows, a pronounced ridge stretches from the Gulf to Quebec. How are these features interacting to influence weather across the Florida Keys?

Breezes are amplified across the Florida Keys waters. Fresh to strong northeasterlies developed before the weekend, and are on track to remain elevated through the start of the week. The eastern coastline trough is expected to reach its peak intensity on Monday, which is also when we are on track to observe strong to near gale breezes. Shower coverage during this period of time will be a bit more difficult to parse. While environmental PWAT is forecast to oscillate between the 50th and 75th percentile values this weekend, the layers to watch will be from the surface to 700 mb. Tonight, drier air can still wrap around across the Lower and Middle Keys. For the second half of the weekend and Monday, the drier air will be washed out by deeper layers of moisture moving over South Florida. In the event the heaviest showers overlap with king tides, anyone in the Keys should take caution near low lying areas.

Forecast confidence after Monday drops quickly. Amplified patterns can be difficult to model and the trough off the eastern coastline is resolved very differently by the ECMWF and the GFS. The GFS kept a stronger surface low near the Bahamas, while the ECMWF lifts the low away as part of a broad wave. This means the Euro resolves light and variable breezes over the eastern Straits on Tuesday, while the GFS sustains fresh to strong breezes. Model consensus, as one could guess, is low. Our forecast leans towards the GFS as being more realistic. High pressure is forecast to linger over the eastern United States for most of the week, and thus the pressure gradient is more likely to be maintained. Check back for updates, because the forecast can change quickly. In the meantime, enjoy the mostly clear skies tonight!

MARINE

Issued at 345 PM EDT Sat Oct 24 2026 A Small Craft Advisory is in effect for all Florida Keys marine zones. Breezes are on track to remain fresh to strong for a prolonged period of time. Near gale conditions, while unlikely, are possible early during the week. Lulls in winds are expected during day time hours, but hazardous marine conditions will be able to return rapidly.

From synopsis: High pressure over the eastern United States and a weak low northeast of the Bahamas will sustain fresh to strong breezes through the weekend and early next week. Peak breezes are expected on Sunday night through Tuesday. Near gale breezes are possible over the Outer Gulf waters. Freshening breezes and pulse of low level moisture may support elevated shower chances on Sunday night and Monday. Breezes are on track to slacken to moderate to fresh by midweek.

AVIATION

(00Z TAFS) Issued at 733 PM EDT Sat Oct 24 2026 VFR conditions are set to prevail as dry air over the Keys will limit precip chances at both TAF sites tonight, but the enhanced pressure gradient will result in breezy north to northeasterly winds with occasional gusts of 20-22 kts. A pocket of higher moisture content will rotate across the area tomorrow which may be enough to generate some scattered vicinity showers around 19Z.

CLIMATE

On this day in 1943, the daily record rainfall of 1.60" was recorded in Key West. Rainfall records for Key West date back to 1871. Also, on this day in 1971, the daily record rainfall of 1.82" was recorded in Marathon. Rainfall records for Marathon date back to June 1950.

PRELIMINARY POINT TEMPS/POPS

Key West 74 83 75 84 / 10 30 40 40 Marathon 74 83 75 84 / 10 40 50 50

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Warning until 5 AM EDT Sunday for FLZ076.

Coastal Flood Advisory until 5 AM EDT Sunday for FLZ077-078.

GM...Small Craft Advisory until 8 PM EDT Monday for GMZ031>035- 042>044-052>055-072>075.