textproduct: Key West

KEY MESSAGES

- Light to gentle southeast to southerly breezes will gradually slacken this morning.

- A typical summertime pattern will continue through around mid week. Rain chances will remain near or slightly below seasonable levels (10-20%), with the warm and muggy conditions continuing.

- A weak Saharan Air Layer is on track to move over the Florida Keys by mid week and may diminish shower coverage. Heat indices may creep towards 110 around mid week.

DISCUSSION

Issued at 400 AM EDT Mon Jul 6 2026

Weak surface through lower level Atlantic ridging will remain across South Florida for the next few days. This will keep breezes light to gentle and broadly out of the southeast. Mesoscale effects will result in winds tending to strengthen slightly during the overnight hours. This flow will ensure slightly above normal temperatures with highs near 90. Dew points will remain in the mid to upper 70s with overnight lows struggling to fall out of the mid 80s and near record warm lows. Weak anticyclonic flow aloft and weak predominantly mesoscale/diurnal forcing below will result in seasonable shower and thunderstorm potential through this period with island driven convection usually ending up on our nearshore gulf side waters.

Deep layered troughing over the eastern United States will begin lifting out on Tuesday. This will allow the western flank of the surface through lower level Atlantic ridge to strengthen slightly while it lifts northward into Central Florida. As a result, surface winds are expected to trend upwards, with peaks in the evening and lulls during the day. This will help to keep highs near 90 but also hold up overnight lows in the mid 80s. Rain and thunder chances may dip slightly as a swath of drier and more stable air moves across the Keys for a fairly short period in the late Wednesday through late Thursday time frame.

Through the latter part of the week, upper level ridging will give way to a weakening cut off upper low retrograding across Cuba. Associated weak lower level troughing is expected to carry westward across our area and be accompanied by a swath of increased lower level moisture. As a result, rain chances may tick up a notch or two towards the end of the work week. Some, not all, statistical guidance is beginning to pick up on this. Expect continued slightly warmer than normal conditions with dew points remaining in the mid to upper 70s.

MARINE

Issued at 400 AM EDT Mon Jul 6 2026

The western flank of an Atlantic surface ridge will remain across South Florida, keeping local breezes light to gentle and generally southeasterly. After mid week, the ridge will strengthen modestly whilst lifting northward into Central Florida. This along with persistent lower pressure in the Caribbean Sea and Cuban diurnal effects will result in freshening east to southeasterly breezes in the late afternoon and evening hours from mid week and beyond. These wind swings are expected to be pronounced and the need for periodic marine cautions is becoming increasingly likely, especially across the Florida Straits.

AVIATION

(00Z TAFS) Issued at 400 AM EDT Mon Jul 6 2026

VFR conditions will prevail at the island terminals today. Surface winds will be light and southeast to southerly.

PRELIMINARY POINT TEMPS/POPS

Key West 92 84 93 84 / 30 10 20 10 Marathon 90 84 90 84 / 30 10 20 10

KEY WATCHES/WARNINGS/ADVISORIES

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