textproduct: Key West

KEY MESSAGES

- Rain chances will slowly increase throughout the weekend as dust concentrations decrease.

- Warm and muggy conditions will continue into the weekend with light and often variable breezes.

- Light winds and a lack of cloud cover suggest the environment may be favorable for waterspouts tomorrow afternoon.

DISCUSSION

Issued at 1014 PM EDT Thu Aug 20 2026 Today's weather across the Florida Keys resembled the more typical August pattern. Cloud line showers dropped almost almost an inch of rainfall at WFO Key West this afternoon, and multiple waterspouts were observed near the Lower Keys. The 00Z KKEY sounding sampled an environment with almost 2 inches of precipitable water with a very well mixed surface layer. While convection earlier this evening was not vigorous enough to stabilize the atmosphere, nighttime cooling will be able to reduce shower coverage for the rest of the night. Surface breezes remain light and occasionally variable along the reef. Even when a thunderstorm neared one of the observation stations, winds were barely able to gust up to 20 knots. The pattern that enabled the col region to stall over the Keys is still in place, for better or worse.

While the environment is not as favorable for rainfall, showers may still form overnight. Lingering outflow boundaries from today's convection and a sea breeze moving off the Florida Peninsula could provide sufficient lift to set off a thunderstorm. Near surface winds, while forecast to become persistent southeasterlies, are expected to remain light. Radiational cooling may be able to lower temperatures closer to near 80 in the event that debris clouds created by today's earlier showers dissipate. Dew points will also remain in the mid 70s. Expect the environment to stay muggy and humid tonight. Cloud lines may become a problem after sunrise, but that is a morning problem.

MARINE

Issued at 1014 PM EDT Thu Aug 20 2026 From synopsis, a split ridge across the Florida Keys coastal waters will support light southeasterly breezes through Saturday, becoming variable in the afternoon hours each day. A high pressure system in the eastern North Atlantic will modestly strengthen and drift westward for the second half of the weekend into early next week. This will support freshening southeasterly breezes, becoming gentle to moderate.

AVIATION

(00Z TAFS) Issued at 1014 PM EDT Thu Aug 20 2026 VFR conditions will prevail at EYW and MTH for the upcoming period. Shower chances will be lower overnight, thus VCSH was removed from the TAFs. Near surface winds, while occasionally variable, will gradually shift southeasterly overnight. The chance for VCSH and VCTS will increase tomorrow after sunrise, with the most favorable conditions near the end of the forecast period.

PRELIMINARY POINT TEMPS/POPS

Key West 82 91 83 92 / 10 10 10 0 Marathon 83 90 83 90 / 10 10 10 10

KEY WATCHES/WARNINGS/ADVISORIES

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