textproduct: Key West

KEY MESSAGES

- Measurable rain chances will remain low through today through early next week, at generally 10% or less.

- Conditions will remain seasonably warm and muggy, but we may see heat index values above 105F, particularly along the Upper Keys, through Sunday.

- A pocket of Saharan Air currently near and north of Hispaniola will slowly move west across our area starting Monday and could linger through Wednesday.

AVIATION

(18Z TAFS) Issued at 127 PM EDT Sun Jun 21 2026 VFR conditions will prevail at both EYW and MTH through the TAF period. There is only a slight chance of showers today therefore no mention of VCSH at either terminal. Light and variable winds will become northeast after sunset.

MARINE

Issued at 1148 AM EDT Sun Jun 21 2026 No watches, warnings, or advisories are currently in effect for the Florida Keys waters. From synopsis, a broad, weak high pressure is centered over the Florida Peninsula. This will maintain a weakened pressure field across the Florida Keys and surrounding coastal waters. As a result, expect winds to be highly variable due to convection developing across South Florida during the afternoon and moving into our waters during the evening and overnight. Thereafter the high will flux in strength, resulting in breezes periodically entering peaks and lulls.

PREVIOUS DISCUSSION

Issued at 444 AM EDT Sun Jun 21 2026

It was another relatively active night across the waters north of the island chain. A residual boundary that likely originated from a cloud line attempting to develop yesterday afternoon, briefly came to life across the Lower Keys. Unfortunately, the single shower that developed fell apart before reaching Key West. However, it did manage to produce around a quarter of an inch of rainfall at the Boca Chica Naval Air Station before it dissipated. Convection remains ongoing this hour but lies just northwest and west of Key West between Smith Shoal Light and the Dry Tortugas. Since the shower did not reach Key West International Airport, and we do not see temperatures fall below 83 degrees before midnight, a new warm low temperature record could be set or tied.

Today will be similar to yesterday in the sense that morning convection will wither shortly after sunrise. Then eyes will turn to the southern Mainland where convection will fire in the afternoon and once again drift over the Upper Keys and the waters north of the island chain. In addition, we may have a long enough period of northeast to east winds in the 850-700 mb layer which may be just enough for a late day cloud line to try and take shape. The atmosphere set- up will also be similar and any showers or thunderstorms that collapse as they enter our waters could be quite frisky. This will lead to locally confused seas and higher winds.

Meanwhile, lurking just north of Hispaniola and Puerto Rico is a decent slug of Saharan Air. This will slowly move in starting late tonight into Monday and linger through Wednesday. The leading edge could provide a slight chance of showers and thunderstorms before the drier, more stable air shuts down most of our prospects for precipitation. Temperatures through the next seven days will hardly budge, however, the introduction of the drier Saharan Air may afford us a somewhat, albeit slight reduction in dew points.

KEY WATCHES/WARNINGS/ADVISORIES

FL...None. GM...None.