Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Nov 11 2022 16:23:56 AWUS01 KWNH 111623 FFGMPD VAZ000-NCZ000-SCZ000-TNZ000-112222- Mesoscale Precipitation Discussion 1121 NWS Weather Prediction Center College Park MD 1123 AM EST Fri Nov 11 2022 Areas affected...Blue Ridge of Western NC and Far Southwest VA Concerning...Heavy rainfall...Flash flooding possible Valid 111622Z - 112222Z SUMMARY...Additional heavy rains associated with T.D. Nicole will pose a threat for some flash flooding across the Blue Ridge going into the afternoon hours. DISCUSSION...As of 1500Z (10AM ET), T.D. Nicole was located 35 miles north of Atlanta, GA and is moving north-northeast at 23 mph. Nicole continues to weaken, but the threat of heavy rainfall continues as moisture lifts north ahead of it into the eastern slopes of the southern Appalachians and with an emphasis expected over the next several hours on the Blue Ridge from western NC through far southwest VA. Enhanced southeast low-level flow will continue to favor strong moisture transport into the eastern slopes of terrain, and the latest VWP data shows as much as 35 to 40+ kts in the 925/850 mb layer around the northeast flank of Nicole helping to facilitate this. The instability parameters are quite modest with much of MUCAPE values of 250 to 500 j/kg, although there are higher values noted just off to the east over the Piedmont. The relative lack of instability will tend to suppress the overall rainfall potential, but the degree of moisture transport and orographic forcing along with anomalously high PWs in general should favor an elevated degree of rainfall efficiency that will help compensate, and it is expected that some of the stronger convective elements that evolve today will be capable of producing 1+ inch/hour rainfall rates. The 12Z HREF guidance supports an additional 2 to 4 inches of rain locally going through the late afternoon hours, and while the heaviest rains in the short-term should be more focused over western NC, these heavier rains will gradually lift farther north begin to impact areas of far southwest VA as well. Given the additional rainfall totals, and moistening soil conditions from earlier rainfall, some areas of flash flooding will be possible heading through the afternoon hours. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!52kwRChf55yXQ3QCOvl8LVqQzqFAgUoYP5NMIremUfjMKPz-UwHp0t8JqXG2QJtpcEBA= AfLTKL6qmcNtSOXQFHIRKSI$ for graphic product... ATTN...WFO...GSP...MRX...RNK... ATTN...RFC...LMRFC...OHRFC...SERFC...NWC... LAT...LON 36948051 36698042 36138103 35698144 35298194=20 35038288 35158312 35598262 36138205 36408162=20 36778115 36938077=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .