486 FXUS62 KFFC 100016 AFDFFC Area Forecast Discussion...Updated for Aviation National Weather Service Peachtree City GA 810 PM EDT Tue Oct 9 2018 .SHORT TERM /Tonight through Thursday Night/... To begin the short term period, deep easterly flow is in place across our forecast area ahead of Hurricane Michael, which will continue to moisten the airmass. As this moistening occurs, there will be thickening cloud coverage and an increasing chance of precipitation. The enhanced cloud cover will inhibit the surface instability, which will in turn limit the chance of thunderstorms this afternoon. Have accordingly capped the coverage of thunderstorms to isolated through this afternoon. The wind gradient has tightened as Hurricane Michael has begun to interact with the ridge in place across the east coast, and therefore gusts of 20 to 25 kts are possible throughout the day today. Michael is currently expected to make landfall along the central Florida panhandle early Wednesday afternoon, then rapidly accelerate northeastward later Wednesday into Thursday. The primary hazards associated with Michael will be heavy rainfall and sustained tropical storm force and possible hurricane force wind gusts. During the height of the storm, sustained winds of 30 to 40 kts will be possible with gusts as high as 65 kts across portions of central Georgia. The strongest winds are expected along and south of a line from Muscogee county to Jefferson county. A Flash Flood Watch is in effect for areas along and south of a line from Madison county to Chattahoochee county, where widespread rainfall totals between 3" and 5" are expected, along with some locally higher amounts. See Hydrology discussion below for more details. Moreover, east-central Georgia will be a favored location for some isolated tornadoes as rainbands in the northeastern quadrant of Michael passes over the area. The worst of Michael is expected to exit the area late Thursday afternoon, with rain chances ending overnight and into the early morning hours on Friday. While confidence is increasing in the storm track as Michael gets closer to making landfall, there still remains some uncertainty regarding impacts. The axis of heaviest rainfall and maximum wind gusts could be subject to change even if minor adjustments to the track are made with respect to speed or location. All interested parties are strongly advised to continue to monitor all forecast updates for any potential developments with Hurricane Michael. Temperatures will remain above climatological normals through the period, with high temperatures in the low to mid 80s. Low temperatures and dewpoints will be in the upper 60s and low 70s, courtesy of the deep moist flow over the area. King .LONG TERM /Friday through Tuesday/... After the remnants of Michael move northeastward out of the area and into the Mid-Atlantic states, strong high pressure will build into the area and remain in place into the early weekend. As a result, long-awaited fall-like temperatures can be expected, with high temperatures in the 70s and low temperatures in the 50s during the weekend and early next week. Models are in fairly good agreement that on Sunday, the high pressure will move off to the east as a frontal boundary approaches the area. This cold front is expected to bring a chance of thunderstorms to the area on Monday into early Tuesday morning. King && HYDROLOGY... Currently, the heaviest rainfall axis associated with Michael is expected to 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 (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 aforementioned I-85 corridor. A Flash Flood Watch has been issued along and southeast of the line from Madison County to Chattahoochee County. && AVIATION... 00Z Update... Ceilings will be lowering to IFR after 06z and gradually improving to MVFR/low VFR by Wednesday afternoon. However...showers and isolated thunderstorms will be increasing across the taf sites tonight and into the day. Deep easterly flow will keep winds east 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...00Z Update... Medium confidence on all elements. 41 && .PRELIMINARY POINT TEMPS/POPS... Athens 69 80 71 79 / 60 80 100 90 Atlanta 71 80 71 79 / 50 70 90 70 Blairsville 66 74 66 73 / 60 70 90 80 Cartersville 70 81 70 78 / 40 70 80 70 Columbus 73 82 73 83 / 40 80 100 70 Gainesville 69 77 70 77 / 60 70 90 80 Macon 72 83 73 82 / 50 80 100 100 Rome 70 81 70 79 / 40 60 80 70 Peachtree City 71 81 71 81 / 40 80 90 80 Vidalia 73 84 75 84 / 60 80 100 100 && .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...41 LONG TERM....King AVIATION...41