Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
823 FXUS62 KKEY 182030 AFDKEY Area Forecast Discussion National Weather Service Key West FL 330 PM EST Tue Nov 18 2025 ...New MARINE, AVIATION, PREV DISCUSSION... .KEY MESSAGES... -Northeasterly breezes freshening from gentle to moderate heading into Wednesday, which will allow temperatures to return to normal values. -Thick cloud cover from a weak low pressure system south of Cuba will linger through the overnight and dissipate on Wednesday. -Deep layers of dry air continue to inhibit shower development through the work week. && .MARINE... Issued at 330 PM EST Tue Nov 18 2025 High pressure located over the eastern CONUS will slowly move into the western Atlantic tonight. The high will then slowly build and support freshening northeast to east breezes during the work week. Although the high will wax and wane at times, expect generally gentle to moderate breezes with occasional moderate to fresh breezes south of the island chain. && .AVIATION... (18Z TAFS) Issued at 330 PM EST Tue Nov 18 2025 VFR conditions will continue to be the predominant through the evening and overnight, outside of any precipitation. Showers across the Straits of Florida will slowly edge northwest towards the Lower Keys. There is a slight chance for an isolated shower to affect the EYW terminal but confidence is too low to include mentions of VCSH at this time. && .PREV DISCUSSION... Issued at 415 AM EST Tue Nov 18 2025 Dry season across the Florida Keys is in full swing; however, there are a couple of interesting features. A weak disturbance south of Cuba is rather perplexing. Mid level water vapor scans from GOES East show a deep layer of dry air over most of Cuba, except a couple pulses of convection. Infrared scans are able to identify the low cloud layer around FL070 to FL 080, which was observed by last night`s sounding and the overcast layer observed by ceilometer are both EYW and MTH. Individuals across the Keys will notice another impact of this cloud layer: warmer temperatures. In contrast to last night`s drop into the lower 60s (mid 50s at Big Pine Key), temperatures remain near 70. Dew points are hovering in the upper 60s, so expect another muggy morning with objects drenched in dew. Today, expect gentle to moderate breezes across the Keys with temperatures returning to near normal values. .FORECAST... GOES East water vapor imagery highlights a broad mid level ridge stretching from the Yucatan Peninsula to Arkansas. That ridge is responsible for sustaining deep layers of dry air across the Florida Keys, and that pattern is not forecast to change during the upcoming week. Breezes will be a bit more dynamic. A high pressure system, presently over the Carolinas, is progged to move into the Atlantic and build towards the Florida Peninsula by midweek. A sharper pressure gradient means moderate breezes for many of the waters around the Keys, so the chance of radiational cooling is low. Weekend weather looks more uncertain. Current numerical model runs show low pressure systems developing over the southeastern CONUS and forcing a cold front into the Gulf. This does not appear to be a strong frontal system, but it would disrupt the pressure gradient and result in light to gentle breezes. Overall, the weather pattern will be more interesting in other parts of the country instead of the Florida Keys. && .PRELIMINARY POINT TEMPS/POPS... Key West 73 81 72 81 / 10 10 0 0 Marathon 73 79 72 80 / 10 0 0 0 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...LIW Aviation/Nowcasts....LIW Data Acquisition.....LIW Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest