textproduct: Key West

KEY MESSAGES

- A reverse cloud line is possible this afternoon. Any developing cloud line will tend to favor waterspout development.

- Small Craft Should Exercise Caution offshore of the Upper Keys due to a brief freshening of winds this afternoon. Breezes will gradually slacken overnight.

AVIATION

(18Z TAFS) Issued at 113 PM EDT Wed Jul 29 2026 VFR conditions will prevail throughout the TAF period with SW winds around 5-10 kts and occasional gusts of 15 kts possible through this evening. Wind speeds will then decrease overnight to 5 kts or less and remain light/VRB into Thursday.

DISCUSSION

Issued at 1030 AM EDT Wed Jul 29 2026 The 12z morning sounding at KEY on this first day of the 2026 lobster sport season sampled a well-mixed adiabatically layer from the surface up to around 940 mb, capped by a weak temperature inversion, and then relatively dry air above. GOES-19 visible satellite imagery is only detecting isolated to scattered cumuli streaming across the Florida Keys and the adjacent marine zones in the mean moderate to southwesterlies. These southwesterlies are a response to the interaction of a stationary front draped across the Mid- Atlantic and a 1024 mb surface high pressure system centered northeast of the Leeward Islands. Under ample solar insolation, land-based surface observations across the Keys are reporting temperatures near 90F already at this early afternoon hour.

For this afternoon and evening, skies should remain generally mostly sunny across the Keys, with temperatures nudging up another few degrees. We will need to monitor the potential for broken cumulus cloud line development across portions of the Keys. However, given the mean wind speeds and the aforementioned dry air above 950 mb, current reasoning suggests any cloud streamer forming along the Island Chain will be weak and quickly dissipating. No changes to the inherited short-term forecast proposed.

MARINE

Issued at 1030 AM EDT Wed Jul 29 2026 Small Craft Should Exercise Caution headlines are posted for the eastern marine zones south of the Upper Keys, including Hawk Channel and the Straits of Florida. In addition, a broken cloud line will also be possible along portions of the Florida Keys. Any developing cloud line will support possible waterspout formation. From synopsis, troughing combined with the western periphery of an Atlantic surface ridge will support moderate to fresh southwest to west breezes across the Keys marine zones, especially over the adjacent nearshore and offshore waters off the Upper Keys. Breezes will gradually slacken overnight through Thursday night, as weak nebulous flow takes over. A col region will set up for late week into the weekend, resulting in a potential period of variable breezes.

KEY WATCHES/WARNINGS/ADVISORIES

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