textproduct: Key West

KEY MESSAGES

- Island cloud line formation will be possible in the late morning or afternoon hours through Monday.

- Waterspouts will be possible with any developing island cloud line.

- Conditions will remain seasonably warm and muggy, with heat indices approaching near 100F each afternoon through early next week.

DISCUSSION

Issued at 414 AM EDT Sun Jun 14 2026 Another June morning, another muggy sunrise across the Keys. Temperatures along the island chain are in the lower 80s with dew points in the mid 70s. KBYX radar returns identify occasional showers across the nearby waters, so showers can develop in the current environment. GOES East satellite derived PWAT estimates a PWAT between 2.1 and 2.2 inches, which does match last night's 00Z KKEY sounding. The environment is so moist that the nighttime microphysics observations make any low altitude cumulus clouds appear washed out. Prevailing light to gentle breezes are being observed along the reef. The most significant difference from yesterday is the absence of a thick cirrus cloud layer. Fewer clouds means more surface heating, and thus more potential for outflow boundaries, pop up showers, or a cloud line if winds stay a bit more easterly. Thus, opting to keep PoPs at 10 percent for the day.

Unfortunately, the atmosphere is on track to become stagnant over the Florida Keys. A broad trough is building over the eastern United States. Over the Atlantic, the environmental high pressure system is distant, centered north of the Cabo Verde Islands. This means a weaker pressure gradient across the country and thus light winds across the Keys. Southerly winds in the 925-700 mb layer also hints at possible dusty layers that could prevent showers. Regardless of the reason, statistical ensembles forecast extremely dry conditions this week. Unfortunately, shower free conditions does not mean lower humidity. June summer is here to stay, and that means we have high confidence heat indices in excess of 100 F will occur this week. Try to manage your time outdoors when possible, because heat sickness can quickly become a problem.

MARINE

Issued at 414 AM EDT Sun Jun 14 2026 No watches, warnings, or advisories are in effect for the waters surrounding the Florida Keys. From synopsis, light to gentle breezes are expected to persist through the middle of the week across the Florida Keys. The combination of a weakened Atlantic high and a broad low over the northeastern United States will cause general veering to the south by tomorrow. A drier pattern is setting up across the Keys, and shower chances are on track to remain very low through the forecast period.

AVIATION

(06Z TAFS) Issued at 414 AM EDT Sun Jun 14 2026 VFR conditions will prevail at both EYW and MTH through the forecast period. There is a chance for a cumulus cloud line near EYW and MTH during the day, resulting in Sub-VFR ceilings and visibilities are possible near isolated showers. Afterwards, rain chances will be near nil.

PRELIMINARY POINT TEMPS/POPS

Key West 89 81 89 82 / 10 10 10 10 Marathon 89 81 90 82 / 10 10 10 10

KEY WATCHES/WARNINGS/ADVISORIES

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