Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
853 FXUS62 KKEY 181518 AFDKEY Area Forecast Discussion National Weather Service Key West FL 1018 AM EST Tue Nov 18 2025 ...New DISCUSSION, 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 provide filtered sunshine through this afternoon -Deep layers of dry air continue to inhibit shower development through the work week. && .DISCUSSION... Issued at 1018 AM EST Tue Nov 18 2025 We have pesky cloud cover this morning that continues to linger across the Florida Keys. These clouds are thanks to a weak low level weather disturbance in the western Caribbean, south of Cuba. This broad feature is producing some convection closer to the center circulation, while producing light showers across the Straits of Florida. These showers have been generally moving towards the Keys but, have also been weakening for the most part. If they do manage to survive, the Lower Keys, especially Sugarloaf Key to Key West, could see some sprinkles or a brief shower. Otherwise, it will remain more so on the cloudier side for this afternoon. Given the low probability of a lone shower moving into the Lower Keys, have opted to keep slight chance PoPs out for the time being. Did make adjustments to winds as winds slightly over-performed overnight and into this morning. Currently seeing near 10 mph for the island chain and 10 to 15 knots for the marine platforms. Otherwise, no other changes were made. && .MARINE... Issued at 1018 AM EST Tue Nov 18 2025 High pressure located over the eastern CONUS will slowly move into the western Atlantic this afternoon and tonight. The high will slowly build and support freshening northeast to east breezes during the work week. Moderate to fresh breezes are possible south of the island chain. Late in the week, a low pressure system traversing the southeastern CONUS may allow breezes to slacken to light to gentle. && .AVIATION... (15Z TAFS) Issued at 1018 AM EST Tue Nov 18 2025 Expecting VFR conditions to be the predominant through the remainder of the morning and into the afternoon. Showers have been attempting to reach the Lower Keys but have been generally dissipating as they approach the EYW terminal. Therefore, will omit mentions of VCSH for now. Otherwise, gentle northeast to east breezes will continue with occasional moderate breeze gusts. && .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 80 73 81 72 / 10 10 0 0 Marathon 79 73 79 72 / 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