075 FXUS62 KFFC 190558 AAA AFDFFC Area Forecast Discussion...UPDATED for Aviation National Weather Service Peachtree City GA 150 AM EDT Mon Apr 19 2021 .PREV DISCUSSION... /Issued 227 PM EDT Sun Apr 18 2021/ SHORT TERM /Today through Monday/... As the short term period begins, a weak disturbance in the upper level flow is moving eastward across central Georgia. A surface low associated with this system is similarly moving northeastward across the Gulf Coast and towards the Atlantic Coast. The heaviest and most widespread showers are south and east of the forecast area as the short term period begins, but some isolated to scattered showers remain possible in the far southern tier through the remainder of the morning hours today. No instability is present across the area, so thunderstorms are not expected this morning. Any additional precipitation that occurs this morning is expected to stay south of a line from Columbus to Macon. Deeper moisture will be pushed to the south and east of our area as drier air and 850 mb cold air advection spread into north Georgia today. Low temperatures will start the morning in the 40s in north Georgia and in the 50s in central Georgia. Meanwhile, an upper level shortwave currently over the Great Lakes region will quickly drop southeastward into the Mississippi Valley this afternoon and towards Georgia later in the day. Precipitation chances are expected to be minimal with this system with only limited low level moisture over the forecast area. High temperatures this afternoon will run near to just below climatological normals across the area, primarily in the 70s. As the shortwave swings through Georgia on Monday, it will help push moisture further south and east away from the forecast area. A dry and seasonal day is expected on Monday as high pressure builds into the area. With highs in the 70s once again and dewpoints dropping into the upper 30s and low 40s during the afternoon, minimum relative humidity values will range from 25-30 percent. While outside of critical fire danger thresholds, the potential for lower RH values will need to be monitored in ensuing forecast updates. King LONG TERM /Tuesday through Sunday/... The biggest change to the long term forecast comes on Tuesday, where the forecast begins. Model trends over the past 24 hours are even drier in the lower levels and seem to be pushing any available baroclinic zone further south well into the gulf. This makes potential interaction with the upper level wave moving over the area more difficult, and at the very least pushes any sfc low that does develop even further to the south of the CWA. As a result, models show little in the way of mid level WAA being able to overspread the area now, and our chances for squeezing out a few showers seem to be diminishing with it. SREF plumes confirm this across much of the short range guidance, as almost no models within the ensemble show any precip in the CWA with the exception of one or two in the far SE portion. With all of this, have decided to decrease PoPs across the entire area, taking out all but a slight chance over portions of central and eastern Georgia. Also removed thunder from the grids, as generating any sort of convection without access to better moisture seems very unlikely. Large trough will swing into the eastern CONUS on Wednesday pushing a potent cold front with it across most of the eastern two thirds of the US. Cold front will traverse the CWA on Wednesday, bringing highs down across the north on Wednesday and the entire CWA on Thursday, where high will only reach into the 60s across most of the area. As my predecessor noted, Wednesday night is now looking to be a potential frost/freeze night, with highs in the low to mid 30s across much of the northern tier. Winds keep up a little, but clear skies should allow for a nice inversion to set up. All counties are within the growing season now, so continue to monitor the coming days for any potential issuance in order to protect any sensitive crops or plants. Other concern starting Wednesday with the frontal passage will be fire wx. High pressure settles in for a few days ahead of the next system over the weekend behind the front though winds will pick up as air mass remains some what progressive. Min RHs look to drop into the 20s for several hours each day and may drop even lower given mixing that longer term guidance may not correctly handle. With lack of recent rains, smaller fuels have already begun to substantially dry and will likely be within critical thresholds. Each ingredient looks to be primed - winds, air moisture, and fuel moisture - so fire danger statements seem to be likely on these days barring a substantial shift in the expected forecast. Moving into the weekend, strong shortwave will be over the 4 corners region. Still are substantial differences between the long range guidance in how the wave is handled, with the GFS now showing a more closed low versus the Euro which still has a broad trough associated with the wave. This has created large timing differences, as Euro moves the shortwave out quickly, but last few runs of the GFS keeps the more closed low back for several days and more zonal flow with small perturbations that allow for the potential for several days of rainfall to occur over the area before finally ejecting the closed low by Sunday. Keeping PoPs in the forecast for several days as a result, with strongest confidence in seeing rainfall on Saturday where highest PoPs are, though Friday night through Sunday all could see rainfall over the area. Lusk && .AVIATION... 06Z Update... VFR conditions expected through the forecast with mainly high clouds and FEW/SCT060 possible. Surface winds NW 3-5kts tonight becoming 9-12kts with gusts to 20kts after 15Z today then decreasing to 3-5kts after 00Z Tuesday. //ATL Confidence...06Z Update... High confidence on all elements. 41 && .PRELIMINARY POINT TEMPS/POPS... Athens 50 74 49 76 / 5 0 0 5 Atlanta 51 72 52 75 / 5 0 0 5 Blairsville 42 66 42 70 / 10 0 0 5 Cartersville 46 72 46 76 / 5 0 0 5 Columbus 51 75 52 77 / 5 0 5 5 Gainesville 49 72 49 73 / 5 0 0 5 Macon 51 76 49 78 / 5 0 5 5 Rome 47 72 46 76 / 5 0 0 5 Peachtree City 48 73 48 76 / 5 0 5 5 Vidalia 57 78 55 79 / 5 5 5 20 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...41 LONG TERM....BDL AVIATION...41