textproduct: Key West

KEY MESSAGES

- Moisture will linger across the region through midweek, supporting rain and thunderstorm chances.

- The primary threat for any stronger thunderstorms will be dangerous lightning strikes. When thunder roars, go indoors. If on a boat, stay low, or go below.

- Heat index values will range from 100-105 degrees daily, with little relief in the muggy conditions overnight. Know the signs of heat stress, take frequent breaks, and stay hydrated.

MARINE

Issued at 330 PM EDT Mon Sep 7 2026

Light and variable breezes will persist tonight through early Wednesday as the Keys remain in a weak and nebulous flow regime. By Wednesday, expecting the Atlantic Ridge to begin sliding westward and leading to freshening easterly breezes. The ridge will then gradually lift north and northeast through the end of the week with breezes entering more of a daytime lull with overnight peaks. Throughout the period, we expect moisture to linger across region, supporting scattered showers and thunderstorms at times.

AVIATION

(18Z TAFS) Issued at 330 PM EDT Mon Sep 7 2026

Shower activity has diminished this afternoon with VFR conditions for both island terminals. However, conditions remain favorable for additional convection to develop this afternoon before drier air moves in. This will bring a brief lull this evening through the overnight.

PREV DISCUSSION

Issued at 501 AM EDT Mon Sep 7 2026

A mostly uneventful night into early morning for KBYX as only a few light scattered showers have been detected in the offshore waters. Temperatures along the island chain are in the mid 80s making for little relief from the day time highs of near 90. According to Nighttime Microphysics skies are partly cloudy. Marine observations across the Reef are reporting light and variable winds. Today is expected to be similar to the past few days as deep tropical moisture continues to linger in the region. MIMIC Precipitable Water is showing around 2.2 inches surrounding our area. Models suggest activity will ramp up in the early to mid morning. A afternoon cloud line development is possible as light variable winds remain light and become southeasterly.

By mid week, the elevated rain chances we have been experiencing for the past few days will return to near normal as high pressure starts to build in. High pressure will also result in a slight freshening of breezes with mid week with periods of gentle to moderate breezes with the possibility of at times fresh. Small Craft Advisory conditions are not expected at this time. Stay tuned for any updates.

PRELIMINARY POINT TEMPS/POPS

Key West 83 92 82 93 / 30 30 30 30 Marathon 83 90 83 91 / 30 40 30 30

KEY WATCHES/WARNINGS/ADVISORIES

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