Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
927 FXUS62 KKEY 280838 AFDKEY Area Forecast Discussion National Weather Service Key West FL 438 AM EDT Tue Jul 28 2026 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... - Rain and thunder chances will remain above normal today, gradually decreasing thereafter. - Light to gentle breezes become gentle to moderate this afternoon, except briefly becoming moderate to fresh off the Upper Keys where Small Craft Should Exercise Caution for increasing winds. - Heat indices may approach 105 to 110 degrees each afternoon for some Florida Keys island communities, especially in the Upper Keys. && .DISCUSSION... Issued at 437 AM EDT Tue Jul 28 2026 CIMSS products shows a rather distinct pattern across the North Atlantic westward across the CONUS. One massive ridge of high pressure remains in place across the central North Atlantic while a second massive ridge is dominating the central United States. In between the two, troughing remains in place across the Eastern Seaboard. At the surface, a trough remains across much of Florida with weak high pressure across the western Gulf and much stronger higher pressure across the western North Atlantic. Marine observations platforms surrounding the Island Chain are recording mainly west breezes near 10 knots. KBYX radar has been quiet for much of the night until the past hour or two. Isolated showers have developed mainly across the Straits of Florida and the SE Gulf with one other cell across the nearshore waters to the north of No Name Key. GOES 19 Nighttime Microphysics imagery shows partly cloudy skies throughout the Keys with mainly low level cumulus and stratocumulus throughout the area. Temperatures along the Island Chain are in the lower to mid 80s and dew points are in the mid 70s. .FORECAST... Surface troughing extends into the Keys for one more day keeping rain chances above normal at 40%. Looking at the global numerical model guidance Total Precipitable Water Normalized anomaly, this makes sense since we still have abundant moisture across the region. A developing low pressure system across the Mid-Atlantic and Northeast combined with high pressure across the North Atlantic will act in tandem with one another creating for a squeeze play across much of Florida. This looks to play out with much of the moisture focused across the central and northern part of the state while the southern part and the Keys get treated to increasingly drier air as it gets funneled in by the high over the Atlantic. This dry air will also get stuck with no where to go and will remain over the Keys for several days. Therefore, starting tonight, rain chances fall to slight chances with some periods late week into the weekend being dried out completely. Since we will have much drier air over us in the coming days, the heat will become the center of the story again. Daytime highs near 90 degrees and in the lower 90s at times and dew points in the mid to upper 70s will create for heat index values of 105 to 110 degrees. As of now, we don`t anticipate Heat Advisory conditions as it should remain just below it. Overnight lows will also not provide for much relief from the daytime heat remaining in the lower to mid 80s in some cases. Developing low pressure off the Northeast and Mid-Atlantic combined with high pressure over the Atlantic will also create for an increased pressure gradient across the area. This will lend to mainly light to gentle southwest to west breezes, occasionally gentle to moderate along the Island Chain, especially the Upper Keys over the next few days. The gradient relaxes for late week into the weekend resulting in a period of light breezes of even variable at times. && .MARINE... Issued at 437 AM EDT Tue Jul 28 2026 Small Craft Should Exercise Caution for briefly increasing winds across the eastern Hawk Channel and the eastern Straits of Florida this afternoon. Otherwise, there are no watches, warnings, or advisories in effect across the Florida Keys coastal waters. From synopsis, troughing just off the Eastern Seaboard will continue to reach southwestward across the far southeast for the next day and be reinforced by another shortwave. This will result in a broad confluence zone remaining draped across northern Florida/Georgia for much of this week. Generally keep light to gentle breezes out of the southwest to west. Breezes will become gentle to moderate towards mid week before slackening back to light to gentle by late week. && .AVIATION... (06Z TAFS) Issued at 437 AM EDT Tue Jul 28 2026 VFR conditions are expected to persist at both EYW and MTH terminals through the TAF period. Near surface winds are expected to remain southwest to west through the period. Chance of showers and thunderstorms are expected today as abundant moisture remains across the area. Much drier air moves in tonight with decreasing rain chances. Since most of the activity is expected to occur from now through the afternoon, VCSH was included in the TAF. && .CLIMATE... On this day in 1916, the daily record rainfall of 7.14" was recorded in Key West. This is also the wettest day ever recorded in July. Rainfall records for Key West date back to 1871. && .PRELIMINARY POINT TEMPS/POPS... Key West 89 83 90 83 / 40 10 10 0 Marathon 90 82 90 82 / 40 10 10 0 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...MJV Aviation/Nowcasts....MJV Data Acquisition.....MJV Visit us on the web at weather.gov/key Follow us on Facebook and X at: www.facebook.com/nwskeywest www.x.com/nwskeywest