678 FXUS62 KFFC 091751 AFDFFC Area Forecast Discussion National Weather Service Peachtree City GA 151 PM EDT Tue Oct 9 2018 .PREV DISCUSSION... /Issued 1204 PM EDT Tue Oct 9 2018/ Updated for 18Z Aviation Discussion. UPDATE... Scattered light showers are ongoing across north Georgia, including the Atlanta metro area. The wind gradient has tightened as Hurricane Michael has begun to interact with the ridge in place across the east coast, and therefore wind gusts have increased to around 20 kts. Michael is a strong category 2 hurricane and is still expected to make landfall along the Florida Panhandle early Wednesday afternoon, and then quickly accelerate into our forecast area on late Wednesday into Thursday. The Tropical Storm Watch has been extended northward and spans south of a line from Chattahoochee to Glascock counties. The Flash Flood Watch remains south of a line from Chattahoochee to Madison counties. King PREV DISCUSSION... /Issued 357 AM EDT Tue Oct 9 2018/ SHORT TERM /Today through Tonight/... Deep easterly flow will continue across the area through tonight ahead of Hurricane Michael. The airmass will continue to moisten, with thickening cloud cover and increasing chances for showers in the short term. Surface instability remains low, so the chances for thunderstorms will remain very low, in the isold/slight chance category. Temperatures will still be a few degrees above normal through the period. NListemaa LONG TERM /Wednesday through Monday/... The main focus of the long term period will center around Hurricane Michael as the remnants move across the CWFA. Michael is expected to make landfall along the Florida panhandle early on Wednesday, and then rapidly accelerate northeastward later Wednesday into Thursday. The main impacts from Michael expected across the CWFA should be felt Wednesday afternoon into early Thursday morning. The main hazards will be tropical storm force wind gusts and heavy rainfall. A Flash Flood Watch has been issued for areas along and south of a line from Madison County to Chattahoochee county (see Hydro discussion). Currently, the strongest wind gusts associated with the storm are expected to impact areas along and south of Warrenton to Macon to Columbus line. However, both the heaviest rainfall axis and wind gust forecast could change if the track of Michael is adjusted even slightly with respect to speed/location. Strong high pressure will build behind Michael through the early weekend. The high center is expected to move offshore by Sunday as a cold front moves into the Lower Mississippi River Valley. The frontal boundary will move east fairly quickly and is expected to move through the CWFA Monday into Monday night. High pressure is expected to return for the middle of the week. If there is one thing to look forward to in the extended forecast, its the more Fall-like temperatures for early next week. Low temps in the 50s! NListemaa HYDROLOGY... Currently, the heaviest rainfall axis associated with Michael will be south and east of a line from Athens to Columbus. The heaviest rainfall is expected to fall Wednesday afternoon through Thursday morning. Widespread totals of 3" to 5" are possible, with some locally higher amounts between 6" and 7". For areas just north and west of the Athens to Columbus line (lets say along the I-85 corridor), will be in the gradient between the highest rainfall amounts to the southeast and the lowest across northwest GA. In the 85 corridor, amounts between 1" to 3" are possible, with some locally higher amounts. If the track/speed of Michael changes, this could make big changes to the rainfall forecast, especially in the I- 85 corridor. Will go ahead and issue a Flash Flood Watch along and southeast of the line from Madison County to Chattahoochee County. .AVIATION... 18Z Update... Isolated to scattered showers are ongoing across north and central Georgia and are expected to remain through the afternoon and evening. Chance too low for a thunder mention for this afternoon and evening, so will cover with VCSH at all TAF sites with TEMPO group for SHRA at the metro sites. Deep easterly flow will keep winds E throughout the period, with winds gusting up to 20-25 kts. More widespread precipitation and stronger winds associated with Michael will move in beginning Wednesday afternoon, particularly across the southern TAF sites at MCN/CSG. //ATL Confidence...18Z Update... Medium confidence on all elements. King && .PRELIMINARY POINT TEMPS/POPS... Athens 81 69 80 70 / 40 60 80 100 Atlanta 81 71 81 71 / 30 40 80 90 Blairsville 75 66 75 66 / 40 60 80 90 Cartersville 81 70 81 69 / 30 40 70 80 Columbus 85 73 83 72 / 40 40 80 100 Gainesville 77 69 77 69 / 30 60 80 90 Macon 85 72 85 72 / 40 50 90 100 Rome 82 70 82 70 / 20 40 70 80 Peachtree City 82 71 82 71 / 30 40 80 90 Vidalia 84 74 86 75 / 50 60 90 100 && .FFC WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch from Wednesday afternoon through Thursday afternoon for the following zones: Baldwin...Bibb...Bleckley... Chattahoochee...Clarke...Crawford...Crisp...Dodge...Dooly... Emanuel...Glascock...Greene...Hancock...Houston...Jasper... Jefferson...Johnson...Jones...Laurens...Macon...Madison... Marion...Monroe...Montgomery...Morgan...Oconee...Oglethorpe... Peach...Pulaski...Putnam...Schley...Stewart...Sumter... Taliaferro...Taylor...Telfair...Toombs...Treutlen...Twiggs... Warren...Washington...Webster...Wheeler...Wilcox...Wilkes... Wilkinson. Tropical Storm Watch for the following zones: Bibb...Bleckley... Chattahoochee...Crawford...Emanuel...Glascock...Houston... Jefferson...Johnson...Laurens...Macon...Marion...Montgomery... Peach...Schley...Stewart...Taylor...Toombs...Treutlen...Twiggs... Washington...Wheeler...Wilkinson. Hurricane Watch for the following zones: Crisp...Dodge...Dooly... Pulaski...Sumter...Telfair...Webster...Wilcox. Tropical Storm Warning for the following zones: Crisp...Dodge... Dooly...Pulaski...Sumter...Telfair...Webster...Wilcox. && $$ SHORT TERM...King LONG TERM....NListemaa AVIATION...King