220 FXUS62 KFFC 201136 AFDFFC Area Forecast Discussion National Weather Service Peachtree City GA 736 AM EDT Mon Sep 20 2021 ...Updated for 12z Aviation Discussion... .PREV DISCUSSION... /Issued 456 AM EDT Mon Sep 20 2021/ SHORT TERM /Today through Tuesday/... Another rinse and repeat forecast, quite literally, wet weather is ahead through the short term one again. Scattered showers will continue continue to lift northward across the area this afternoon as the CWA remains downstream of the mid/upper low over the Arklatex region. PWAT values remain well above climatological avg, around or above 2". Current forecast additional rainfall amounts through tomorrow range from 1-2" totals across much of the northern sector of the CWA, with locally higher amounts across the NE GA mtns. Heavy rainfall remains the primary concern, especially for areas highlighted in the ongoing Flash Flood Watch where the pockets of heaviest rainfall totals have so far been concentrated. Only major changes to the current Flash Watch is the removal of portions in the SW CWA, and extending the watch through 00z this evening. Can't rule out the extension of the current FFA towards the NE GA corner later today, but given low QPE from yesterday across that area, confidence is too low to pull the trigger for issuance at this time. Morgan LONG TERM /Tuesday Night through Sunday/... An upper level trough continues to march eastward across central CONUS and will dig southeastward into the ArkLaTex region at the beginning of the long term forecast period. The tropical airmass that has been lingering for the past several days has become sufficiently saturated from persistent upper level southwesterly flow from the Gulf of Mexico. As a result, elevated PoPs for Tuesday overnight remain in the forecast with a chance of thunderstorms possible, especially associated with any small upper level disturbances ahead of the surface frontal passage. GFS and Euro show good agreement on timing of the surface front impacting the northwest sector of our CWA by Wednesday. As the front progresses southeastward overnight Wednesday, the upper level trough transitions into a cut off low and ejects northeastward into the Great Lakes region. At the moment, the dynamic setup ahead of the front does not lend itself to widespread severe weather. However, low level shear and moderate instability Wednesday afternoon will allow for a chance of isolated strong storms where damaging wind gusts and heavy rainfall are the main threats. Highest QPF is expected to be in areas of elevated terrain in North Georgia, but with PWAT values ranging from 1.75 to 2.25 inches, periods of locally heavy rainfall will be possible across the entire CWA. Enhanced cloud cover from the beginning of the period through Wednesday overnight will limit diurnal temperature, where lows drop into the 60s to 70s and highs in the 70s to 80s. Once the front passes through early Thursday, high pressure begins to build in across the CWA. Flannel fans will rejoice as cooler than average temperatures and dry conditions dominate the weather pattern throughout the rest of the forecast period. High temperatures in the upper 60s to low 80s will be expected with low temperatures in the 50s to low 60s. Some mountainous areas will drop into the upper 40s for low temperatures. KAL && .AVIATION... 12Z Update... Widespread IFR/MVFR cigs this morning with SHRA/RA across the metro TAF sites this morning. Expecting this trend to continue through with not much improvement during the day, staying BKN/OVC with IFR/lower end MVFR cigs through the afternoon thanks to persistent RA/SHRA. Cigs should lower once again to IFR moving into tomorrow night. Winds remain from the east with speeds increasing to 8-12kts today, with some gusts up to 15-17kts possible during the late afternoon. //ATL Confidence...12Z Update... Medium confidence on all elements. Morgan && .PRELIMINARY POINT TEMPS/POPS... Athens 75 69 79 68 / 80 60 70 60 Atlanta 75 70 80 68 / 80 50 60 60 Blairsville 71 65 75 63 / 70 60 70 70 Cartersville 76 69 81 67 / 80 50 60 60 Columbus 80 71 84 70 / 70 50 60 40 Gainesville 73 68 77 67 / 80 60 70 60 Macon 79 71 84 70 / 70 40 70 40 Rome 76 70 82 68 / 80 50 60 60 Peachtree City 77 70 82 67 / 80 50 60 50 Vidalia 80 72 84 72 / 70 50 80 40 && .FFC WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through this evening for the following zones: Bartow...Carroll...Catoosa...Chattooga...Cherokee...Cobb... Coweta...Dade...Douglas...Fayette...Floyd...Gilmer...Gordon... Haralson...Heard...Meriwether...Murray...North Fulton... Paulding...Pickens...Polk...South Fulton...Troup...Walker... Whitfield. && $$ SHORT TERM...Morgan LONG TERM....KAL AVIATION...Morgan