textproduct: Key West

KEY MESSAGES

- Rain chances will only reach 10% over the next few days.

- Conditions will remain seasonably warm and muggy, but Wednesday and Thursday may see heat index values above 105F, particularly along the Upper Keys.

DISCUSSION

Issued at 1050 AM EDT Tue Jun 16 2026 Weather conditions have seen very little change compared to 24 hours ago as high pressure remains the dominant synoptic feature. Our KBYX radar is detecting a few isolated showers across the distant Florida Straits, but these are gradually waning. Even though there are showers occurring within our forecast area, the environment isnt very conducive to sustain any activity. The 12Z KKEY sounding from this morning showed an unimpressive sounding with just under 500 J/kg of ML CAPE. Even though winds through the lower levels were veering with height, there was still some low level inhibition in place. The calculated PWAT was 1.64 which is just shy of the daily mean of 1.78, and satellite derived PWAT shows a widespread area of similar average values across the region. However, there is a narrow corridor of below average PWATS over the eastern portion of our forecast area, so the moisture profile across the area just isnt necessarily impressive. Another component to our lack of activity is the southerly flow at the surface, and we will likely be shadowed by Cuba today in this regime.

Surface observations currently show temperatures in the upper 80s with dew points in the mid to upper 70s. Were still a few hours away from peak heating, and with little cloud cover we should have no issues coming up a couple of more degrees. This will result in a moderate heat risk along the entire island chain this afternoon.

The inherited forecast is unfolding as expected, so no changes are needed with this morning update.

PREV DISCUSSION

Issued at 344 AM EDT Tue Jun 16 2026 High pressure located in the southwestern North Atlantic and stretching well west into the Gulf Basin will maintain deep layer subsidence across the region. This coupled with a south-southeast steering flow will only add to the inhibition of any shower activity for today. Meanwhile, remnants of a tropical wave that moved across Mexico will enter the northwest Gulf waters off the Texas coast and move along the periphery of said high up into the North Gulf States this week. At the same time, the high pressure will strengthen slightly, maintaining its grip across the Florida Keys. This will not only keep rain chances very low (near 10 percent or less), but it will briefly allow winds to increase slightly Wednesday through Friday.

In addition to a potentially extended dry period, dew points and temperatures will be slowly creeping upward through the week. This will result in heat indices reaching and exceeding 100 degrees this week, especially in the Upper Keys. This will lead to an increase in the heat risk for the Keys, particularity those more sensitive to heat. Conditions will be borderline for heat-related products and will be reassessed as the week progresses. Regardless, extra precautions should be taken this week if you plan on being outdoors for an extended period of time.

MARINE

Issued at 1050 AM EDT Tue Jun 16 2026 There are no watches, warnings, or advisories in effect across the Florida Keys local waters. From synopsis, light to gentle breezes will persist through the middle of the week across the Florida Keys coastal waters. Starting Tuesday night and Wednesday, the Mid-Atlantic high will begin to strengthen and support slightly fresher breezes through the end of the week. Shower and thunder chances are expected to remain very low through the forecast period.

AVIATION

(15Z TAFS) Issued at 355 AM EDT Tue Jun 16 2026 VFR conditions will prevail with FEW skies near FL020 becoming SCT over the second half of the TAF period. Rain chances at either air field will be near zero through most of the day, and only increase to 10 percent tonight. Southeast to south surface winds arent expected to cause any crosswind concerns due to the light nature of these winds at 5 to 10 knots.

KEYS WEATHER HISTORY

On this day in 1906, a category one Hurricane moved slowly to the north-northeast crossing what is now the seven mile bridge. Instrumentation in Key West recorded a minimum pressure of 29.62" and a peak wind of 42 mph.

PRELIMINARY POINT TEMPS/POPS

Key West 90 82 91 82 / 10 10 10 20 Marathon 88 82 88 82 / 0 10 10 10

KEY WATCHES/WARNINGS/ADVISORIES

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