Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
068 FXUS62 KKEY 231944 AFDKEY Area Forecast Discussion National Weather Service Key West FL 244 PM EST Sat Nov 23 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 244 PM EST Sat Nov 23 2024 A magnificent day of weather is ongoing across the Florida Keys. Temperatures have reached around 70 degrees on most islands, with dew points in the mid to upper 50s. A majority of the island chain and surrounding coastal waters have been shadowed by the mainland in terms of winds, with the Lower Keys being the only area seeing winds above 5 to 10 mph. CIMSS MIMIC TPW places an extremely dry airmass over a majority of the eastern U.S, and clouds are hard to come by this afternoon. A broad field of stratocumuls is located west of the Florida Peninsula in the Gulf, but the Keys are seeing a rare clear sky day. Not much change in the sensible weather across the Florida Keys is expected overnight. The main question is just how low temperatures will get on the protected areas of the larger islands. Winds may be light enough due to decoupling to allow for some radiational cooling. The expected clear skies will also play a large part in this. Dew points will be in the lower to mid 50s, so we may see the first temperature measurements in the 50s of the season in the Lower Keys. Otherwise, temperatures will generally range from 60 to 65 degrees. By tomorrow morning, the high over the Mississippi Valley that has provided us with the extended period of northerly breezes will start its trek east to southeastward. In response, Our winds will begin to veer to the northeast to east. Both temperatures and dew points will begin to climb back closer to climatology as a result. There is some discrepancy between the ECMWF and GFS MOS guidance as to how much the temperature will recover, so have stuck with the middle ground between the two. On Monday, the high will be straddled across Florida. Steering flow across our area will be from the east to southeast, and some of the moisture that has been lurking to our south will likely creep back towards the Keys. This will occur in conjunction with troughiness that is expected to develop over the Gulf on Sunday sliding over Florida. This will be the best shot that the Keys have to see a few isolated showers, but current thoughts are that most of the activity that manages to develop will remain in the Straits of Florida on Monday and Tuesday. Thereafter, a continued benign forecast is on tap for the Florida Keys. Generally zonal flow and dry air will keep the region convection free through most of next week. Global models are suggesting another frontal passage by late next week. We will continue to monitor this, but we will also continue to enjoy this wonderful airmass from our last front before we start wishing for another front! && .MARINE... Issued at 244 PM EST Sat Nov 23 2024 There are no watches, warnings, or advisories in effect for the Florida Keys coastal waters. North to northeast breezes have slackened this afternoon, and gentle to occasionally moderate breezes will prevail through the weekend. Breezes will gradually veer to the northeast to east through midweek as a broad high pressure system becomes established over the southeastern United States. Dry weather will persist across the Florida Keys waters through Monday with a possibility of isolated showers, mainly over the Florida Straits, on Tuesday. && .AVIATION... (18Z TAFS) Issued at 244 PM EST Sat Nov 23 2024 Deep layers of dry air from the low to upper atmosphere will support prevailing VFR conditions at EYW and MTH through 18Z. Northeasterly breezes will persist with speeds between 5 and 10 knots. Occasional gusts are expected, but not at a high enough frequency to warrant an inclusion in the TAFs. In a rarity for the Keys, SKC conditions are expected through the period. && .CLIMATE... In 1905, local standard time was changed to the seventy-fifth meridian time, made by omitting the hour between 11 a.m. and noon, on Thursday, November 23, 1905. This action was taken "in order that the time on the city clocks might be the same as that of the naval station, the telegraph office, and the ships calling there." && .PRELIMINARY POINT TEMPS/POPS... Key West 67 75 72 79 / 0 0 0 0 Marathon 66 75 71 80 / 0 0 0 0 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...NB Aviation/Nowcasts....AJP Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest