Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Aug 08 2024 09:02:05 AWUS01 KWNH 080902 FFGMPD VAZ000-NCZ000-WVZ000-SCZ000-081500- Mesoscale Precipitation Discussion 0833 NWS Weather Prediction Center College Park MD 500 AM EDT Thu Aug 08 2024 Areas affected...Northern SC...Central and Southern NC...Southwest to South-Central VA Concerning...Heavy rainfall...Flash flooding likely Valid 080900Z - 081500Z SUMMARY...T.S. Debby will continue to weaken this morning as it advances further inland across the coastal plain of the Southeast, but will continue to promote extremely heavy rainfall. Numerous to widespread areas of flash flooding are expected to continue in association with Debby, with considerable to locally catastrophic impacts. DISCUSSION...The early morning GOES-E IR satellite imagery in conjunction with radar and surface observations shows T.S. Debby moving northwest and inland across the SC coastal plain. Cold convective tops are noted across the northern semicircle of the storm with multiple bands of strong convection continuing to produce extremely heavy rainfall rates that are occasionally on the order of 1 to 3 inches/hour. Much of this is occurring over central to southeast NC and is aligned with a corridor of strong moisture flux convergence with the aid of a southeast low-level jet of 50+ kts. Coinciding with this is also the transport of increasing buoyancy in the boundary layer with MLCAPE values across southeast NC of 1000 to 1500 J/kg. There is also a fair amount of low-level shear which has been fostering these organized convective bands with embedded mesocyclone activity which is further enhancing the rainfall efficiency and related rates. Debby is increasingly coming under the influence of shortwave energy dropping down across the TN Valley and the upper-level flow is becoming increasingly divergent across the southern Mid-Atlantic region which should help favor the poleward advance of heavy rainfall with Debby going through the morning hours. This will allow for the heavy rains and embedded stronger convective elements over central NC to begin overspreading southwest to south-central VA by later this morning. Rainfall rates will remain maximized in the stronger convective bands around the northeast quadrant of Debby's circulation, and there will continue to be significant concerns for cell-training that will favor enhanced rainfall amounts. Given the rain rates of 1 to 3 inches/hour, and the concentrated corridors of cell-training, some additional rainfall amounts by late this morning may reach 3 to 6 inches, with isolated heavier totals not out of the question. Therefore, numerous to widespread areas of flash flooding are expected to continue this morning in association with Debby, with considerable to locally catastrophic impacts where the heaviest rains occur. This will include a significant urban flash flood threat from Greensboro to the Raleigh-Durham area, with areas near and to the north of Wilmington also at risk. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8x1WWiwMEP3PvyPmY3lGYxD2q1V32hmZxV9PirKGyhEXuMH8ZyclE1v40KrevQsJfclj= _5Qc0_uU-k2tBjilynT3tlE$ for graphic product... ATTN...WFO...AKQ...CAE...GSP...ILM...LWX...MHX...RAH...RNK... ATTN...RFC...MARFC...OHRFC...SERFC...NWC... LAT...LON 37757991 37587868 36797769 35777694 34497664=20 33727731 33567830 34087933 33838017 33748078=20 34008139 34718177 36038163 37178084=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .