956 FXUS62 KFFC 292352 AAA AFDFFC Area Forecast Discussion...UPDATED National Weather Service Peachtree City GA 652 PM EST Sat Dec 29 2018 .UPDATE... For 00z TAFs/Aviation. && .PREV DISCUSSION... /Issued 253 PM EST Sat Dec 29 2018/ SHORT TERM /Tonight through Sunday Night/... Models in close agreement on timing of the next wave of rain to move across the CWA. The next short wave is already generating showers across southern AL and southern MS. This will spread northeast through the afternoon moving into the southwest part of the CWA late this afternoon and across the rest of the CWA this evening and continuing into tonight. Have raised pops to likely and categorical for tonight. Models vary on the amount of precip with the NAM being the highest and the GFS being the lowest. The new ECMWF is a good compromise and the latest WPC guidance falls more in line with the ECMWF. The additional rainfall could prolong the current river/creek flooding or possibly push some rivers back into flood. However the expected QPF is not anticipated to create flash flooding and therefore a Flash Flood Watch will not be issued at this time. The main area of precip will exit into the Carolinas and Tennessee late Sunday and Sunday night bringing a lull in the rain Sunday afternoon into Sunday night. With a very moist atmosphere and a good cloud cover, overnight lows will remain well above normal. MOS Guidance MAV/MET blend has been doing well for overnight lows and have followed suit. 17 LONG TERM /Monday through Saturday/... No changes made to the extended forecast. Stationary front stalled just south of forecast area, will start to lift north Sunday night through Monday as the upper low lifts through the southern Plains into the Great Lakes area by Monday night. The next upper low digs into the desert southwest through midweek as the surface front moves across the gulf coast states and Georgia. Surface front is slow to move through the forecast area and with some instability noted with the front on Tuesday have continued slight chance of thunder for Tuesday. extended models diverge with handling of the next system, with GFS taking a faster and more southern route with the surface low/front. As the upper low ejects across the gulf coast states Wednesday into Thursday a surface low develops over east Texas and moves across the gulf coast and Georgia on Thursday we should see an end to rain/precipitation. While there continues to be some uncertainty if cold air can move across portions of north Georgia Wednesday night into Thursday we should see a mix of rain/snow with light accumulations - of less than an inch - possible. Have stayed close to guidance temperatures through the extended periods. Atwell/01 && .AVIATION... 00Z Update... Showers rapidly approaching from the SW, will eventually fill in around ATL and surrounding sites btwn 03-06z. Lower ceilings will follow quickly behind with MVFR to IFR cigs advecting north overnight. Some discrepancy btwn NAM and GFS with the NAM faster and more aggressive with dropping ceilings quickly with the steadier rain overnight. Leaned towards the more reasonable NAM with IFR cigs already btwn KDHN (Dothan) and KCSG. Challenging to pinpoint rain bands into Sunday but IFR ceilings (and vsbys) likely for much of the day with pockets of -RA or DZ around. //ATL Confidence...00Z Update... Medium on timing of VFR to MVFR to IFR ceilings tonight. High all other elements. DJN.83 && .PRELIMINARY POINT TEMPS/POPS... Athens 50 56 49 67 / 80 80 40 40 Atlanta 50 57 52 68 / 80 80 40 40 Blairsville 44 54 47 62 / 70 70 60 70 Cartersville 47 55 51 68 / 80 80 60 50 Columbus 55 64 57 72 / 70 70 20 30 Gainesville 48 55 49 64 / 80 80 40 50 Macon 55 62 55 73 / 70 70 20 30 Rome 46 53 51 69 / 80 80 60 50 Peachtree City 50 58 52 69 / 80 80 30 40 Vidalia 59 71 60 76 / 50 50 20 20 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...17 LONG TERM....01 AVIATION...DJN.83