Marine Weather and Tide Forecast for Big Pine Key, FL

DISCUSSION
Issued at 1000 PM EDT Sat Jul 11 2026 We have seen nearly a complete turn around this evening when compared to 24 hours ago! The offending trough axis lifted out of our area, and we have been left with a blanket of clouds overhead.
The 00Z KKEY from this evening shows a notable influence from Saharan Air Layer (SAL) in the lower levels, but a modestly thick layer of stratus clouds is around 21,000 to 25,000 feet AGL. The SAL has kept conditions unfavorable for shower development, and the stratus layer has helped to keep our temperatures from getting too unbearable. The radar is showing some returns across the area but it's actually detecting some of the cloud cover where the radar beam is intercepting the cloud layer. Our ASOS sites at both Key West and Marathon International Airports only report cloud heights up to 12,000 feet (for aviation purposes) so they are currently reporting mostly clear skies, but a quick look at GOES-19 Cloud Top shows that our skies are anything but clear.
With the SAL layer so clearly present aloft, rain chances will stay very low tonight. Hi res guidance suggests one or two very light showers may develop near the southern tip of the peninsula during the overnight hours, so we'll go ahead and maintain a slight chance (10%) of rain just in case something drifts over the island chain.

Temperatures are also drastically different compared to last night. Current observations are reporting temperatures in the mid 80s with heat index values in the upper 90s. 24 hours ago, temperatures were anywhere from 5 to almost 10 degrees cooler, and heat index values were unable to be calculated. Daytime heating combined with our blanket of cloud cover will help to insulate us, and temperatures should only come down a couple of degrees overnight.

No changes are proposed for this evening update.

MARINE
Issued at 1000 PM EDT Sat Jul 11 2026 There are no watches, warnings, or advisories in effect for the Florida Keys local waters. High pressure across the area will maintain gentle to modestly moderate east to southeast breezes, and these will tend to peak in the evening and night before slackening slightly in the morning and afternoon. Rain chances are expected to remain very low, less than 10%, over the beginning of the new week.

AVIATION
(00Z TAFS)
Issued at 1000 PM EDT Sat Jul 11 2026 VFR conditions will prevail at both island terminals with only occasional reports of FEW to SCT clouds near FL025, but an OVC deck is sitting somewhere around FL210. Saharan dust advecting into the area in the lower levels will keep both sites rain free through the TAF period. East to occasionally southeast winds will remain at 10 to 15 knots initially before slackening to near 10 knots.

PRELIMINARY POINT TEMPS/POPS
Key West 83 92 83 92 / 10 10 0 10 Marathon 84 90 83 90 / 10 10 10 10

KEY WATCHES/WARNINGS/ADVISORIES
FL...None.
GM...None.