858 FXUS62 KMFL 231452 AAA AFDMFL Area Forecast Discussion...UPDATED National Weather Service Miami FL 1052 AM EDT Fri Oct 23 2020 .Update... A generally dry start to this Friday except for a band of showers that has persisted over southern Palm Beach County this morning. Have tweaked the hourly PoPs to account for this continuing activity. Otherwise, the previous forecast philosophy is on track with no additional updates anticipated through midday. Updated zones have been transmitted also showing these changes for the rest of the morning. Have a wonderful Friday! && .Prev Discussion... /issued 756 AM EDT Fri Oct 23 2020/ Aviation... Generally VFR though some showers and storms are possible with a focus around PBI this morning. Additional activity is possible later in the day including the late morning, afternoon, and evening. Greater convective coverage returns late in the forecast period on Saturday. Generally easterly flow will continue through the period. Sub-VFR possible around convection with short-fused amendments necessary for IFR/LIFR impacts. Prev Discussion... /issued 319 AM EDT Fri Oct 23 2020/ .FLOOD WATCH FOR SE FLORIDA CONTINUES INTO THE WEEKEND... Discussion... Short Term (Friday-Saturday): Models begin the forecast period by depicting a deepening large mid level trough across the central CONUS, with an associated frontal boundary stretching from the Great Lakes region down to northern TX. Meanwhile, the western edge of a broad ridge remains right along the eastern seaboard, and Hurricane Epsilon gradually migrates into the eastern Atlantic. The described synoptic scenario will bring one more day of robust easterlies across SoFlo, but with less gusty periods as pressure gradients begin to relax. This is in response of the departure of Epsilon, and the migration southward of the aforementioned front, which will begin eroding the ridge to our north. Today, the easterly flow will keep bringing moisture advection from the Atlantic, with POPs in the 30-40% range from advection alone. There is the possibility of having an area of disturbed weather over the western Caribbean trekking mainly NW and passing very close to SoFlo during the weekend. This will further enhance the deep moisture over the area, bringing chances of rain into the likely range on Saturday. So, even in the short term, there is plenty of uncertainty since models still have a hard time showing consensus on the potential for development of this feature. The National Hurricane Center will continue to closely watch the progress of this feature, currently labeled as a trough of low pressure. But it seems prudent to follow the increasing trends in models towards higher rain coverage Saturday afternoon and carry POPs in the 60-70 percent range for much of the CWA at least. With all this in mind, the Flood Watch currently in effect will be extended through the weekend, since even with a break today from widespread heavy downpours, seems that the threat for localized flooding will again be in place on Saturday. Also, with all the rain from previous days, many locations remain saturated and it won't take much for water to start ponding on metro areas. Temperatures remain warm with highs in the mid to upper 80s each afternoon. Long Term (Sunday-next Friday): Sunday A low-level trough originating in the Carribean waters is forecast to progress northeastward into the southern Atlantic waters. This feature has tropical characteristics, with forecast PWI (precipitable water indices) as high as 2.5 ins. in some prog solutions. Furthermore, a stout low-level (850 hPa) jet appears intact on the easterly periphery of this feature, which will be capable of impressive moisture flux quantities and supportive of deep tropical convection. While widespread rainfall will likely encompass this feature, there is very low spatial certainty (regarding impacted locations). The GFS suggests that the wave stays well east of South Florida, generally affecting the Bahamas. ECMWF resembles more of a "reasonable worst-case" scenario, where the surface trough lingers much closer to the southeast Florida coastline. The primary concern through the end of the weekend is localized flooding, which may become more of an areal threat if the feature nears southeastern Florida. There could also be a low-end severe weather threat, with some model solutions (particularly ECMWF) indicating SFC-6km bulk shear values in the 20-25kt range with a 500 hPa shortwave trough lingering over the region. This threat is very conditional however, and confidence is presently low. Monday through Friday The aforementioned 500 hPa shortwave trough progresses easterly into the western Atlantic, with height rises aloft in it's wake. Synoptic scale subsidence will cause the low-level wave to becomes diffuse, quickly losing it's robust tropical nature. Rain chances still remain possible Monday, however much lower, with PoPs generally no greater than 40 across South Florida. By Tuesday, the upper ridge of high pressure elongates, with South Florida generally under the eastern periphery of this feature. Dry air will usher in beneath this feature, which will generally quell any widespread storm activity. Storms that do develop will generally be short-lived and benign in nature, bereft of sufficient moisture, instability, and shear to sustain themselves. This pattern generally remains dominant through at least the middle of the week, and possibly through Friday as well. Maximum temperatures are forecast to be in the mid 80s for most of the region, which is slightly cooler than seasonable for this weekend due to the increasing cloud cover/rainfall with the surface trough. An increasing trend into the upper 80s ensues Monday with higher pressure building back in. Marine... Abundant moisture over the area will allow for scattered to numerous showers and storms to continue through much of the forecast period. Winds and seas could be locally higher in and around any shower or thunderstorm. Meanwhile, a trough of low pressure in the western Caribbean is being monitored by the National Hurricane Center for any potential development as it gradually migrates closer to the area during the weekend. Beach Forecast... Swells from Hurricane Epsilon and persisting robust easterly winds will again combine today to keep a high rip current risk through this evening along the Atlantic beaches. It is possible that the high risk will be extended through Sunday. As we move on from the new moon and approach the first quarter moon, the astronomically high tides should begin to diminish closer to predicted values. && .Preliminary Point Temps/PoPs... West Palm Beach 84 75 85 74 / 30 20 60 50 Fort Lauderdale 86 77 85 76 / 40 30 70 60 Miami 86 77 85 76 / 40 30 70 60 Naples 88 73 88 73 / 30 20 50 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...Flood Watch through Sunday evening for FLZ068-072>074-168- 172>174. High Rip Current Risk until 8 PM EDT this evening for FLZ168-172- 173. AM...None. GM...None. && Update...02/RAG