Area Forecast Discussion
Issued by NWS Atlanta, GA
Issued by NWS Atlanta, GA
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599 FXUS62 KFFC 281132 AFDFFC Area Forecast Discussion National Weather Service Peachtree City GA 732 AM EDT Fri Jun 28 2024 ...New 12Z Aviation Discussion... .SHORT TERM... (Today through Saturday) Issued at 334 AM EDT Fri Jun 28 2024 A weak upper trough extends from the mid-Atlantic states across the S portion of our County Warning Area (CWA). At the surface, a weak quasi-stationary front is presently draped across N GA. These features will continue to aid in shower and thunderstorm development across the area. Around midnight, isolated moderate showers developed near the aforementioned front across N GA. As of this writing, most of that activity had weakened. However, over the past hour, scattered showers have begun to develop from near Columbus to Macon. This activity is moving slowly northward. This area has the highest CAPE values (around 1000 J/kg), coupled with weak dynamic forcing as well as some isentropic lift. This activity may begin to weaken over the next couple of hours as it continues moving into an area of less favorable instability and forcing. However, this in indicative of the atmosphere being supportive for more convection once daytime heating kicks in. Scattered shower and thunderstorm activity is expected again today across much of the area, with numerous storms SE of Macon. Most storms are expected to remain below severe limits, although an isolated, low-end severe wind gust is possible in the heaviest thunderstorms due to precipitation loading with precipitable water values running around 1.75". Additionally, the high atmospheric moisture content and slow storm motion may lead to some localized flooding in the heaviest storms. Dynamic forcing should be on the decline for Saturday, as the surface front dissipates and the upper level trough weakens. However, models indicate that precipitable water values will continue to increase. This, coupled with increased instability, may lead to an uptick of shower and thunderstorm activity, particularly across the N half of the CWA. There is a bit more uncertainty regarding this scenario, and have thus tweaked NBM PoPs down a bit. However, areas N of the Atlanta metro area will have 70+ PoPs ranging to around 50 percent near and S of Macon. Forecast high temperatures each day will range from near 80 in the NE mountains to the mid 90s across the SE portion of the area (2 to 5 degrees above normal). Lows tonight will range from the mid 60s in the highest terrain of the NE to the lower to mid 70s elsewhere (10 degrees above normal in the NE, 4 to 7 degrees above normal elsewhere). /SEC && .LONG TERM... (Saturday night through Thursday) Issued at 334 AM EDT Fri Jun 28 2024 Beginning the long term period with Sunday, the dampened 500 mb ridge axis continues over the area and westward into the southwest. Meanwhile to the north of the ridge, several troughing features attempt to deepen as they move east every couple of days through the patten. On the southern edge of these troughs there is just enough vorticity to move through the ridge and affect portions of GA through the long term. Models are also forecasting PWATs at 2+ inches through the end of next week which are above the 90th percentile for this time of year (1.80-1.90"). This in combination with the pushes of vorticity into the area results in increased rain chances through the long term. It is also summer which means CAPE values are forecasted to be between 1000-2000 J/kg every afternoon and evening resulting in increased thunderstorm chances too. Overall a very summer like pattern. Despite the increased rain chances most afternoons, accumulations over the next 7 days range from 0.10"- 1.5", so overall still not a lot of rain. With the increased moisture, dewpoints will also be increased with values in the mid 70s through the beginning of next week. This in addition to the temps reaching into the mid to upper 90s will result in heat indices being in the 100-104 range Saturday and potentially up to 108 Sunday. Only minor relief from these heat indices is expected on Tuesday where heat indices are currently forecasted below 100. Again overall a very summer like pattern for much of Georgia as we begin the month of July with above average temps. Hernandez && .AVIATION... (12Z TAFS) Issued at 730 AM EDT Fri Jun 28 2024 An area of 400-800 foot cigs and some patches of mostly light fog have developed near and S of the Atlanta metro area early this morning. These clouds should begin to erode and lift by early to mid- morning. A band of showers has been progressing NNE N of the Macon area. This activity should slowly weaken as it moves into a less favorable environment early this morning. Scattered thunderstorms are expected to develop by late morning or early afternoon across the region. Light, mostly SE winds this morning will pick up a bit during the day, with directions veering toward S. Will keep easterly component at ATL through the day, with an eventual shift to SW possible after midnight tonight. //ATL Confidence...12Z Update... Medium on IFR cigs and thunderstorm timing. High on remaining elements. SEC && .PRELIMINARY POINT TEMPS/POPS... Athens 72 92 74 94 / 50 60 30 70 Atlanta 74 91 76 94 / 40 60 30 70 Blairsville 70 84 69 86 / 50 80 40 80 Cartersville 73 91 73 92 / 40 70 30 70 Columbus 75 93 75 95 / 30 60 30 80 Gainesville 73 90 75 92 / 50 70 30 70 Macon 73 94 74 94 / 30 50 20 70 Rome 74 93 74 94 / 30 70 30 70 Peachtree City 73 92 73 94 / 30 60 20 60 Vidalia 74 95 76 95 / 40 60 30 80 && .FFC WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...SEC LONG TERM....Hernandez AVIATION...SEC