ZCZC SPCSWOMCD ALL ACUS11 KWNS 312356 SPC MCD 312356 NYZ000-NJZ000-PAZ000-MDZ000-DEZ000-VAZ000-010200- Mesoscale Discussion 2324 NWS Storm Prediction Center Norman OK 0556 PM CST Tue Dec 31 2024 Areas affected...Parts of the Mid Atlantic Concerning...Severe potential...Watch unlikely Valid 312356Z - 010200Z Probability of Watch Issuance...20 percent SUMMARY...Strong thunderstorms will spread northeastward through the evening. Small to marginally severe hail and locally gusty winds remain possible. A brief tornado also cannot be ruled out near the Delmarva region. DISCUSSION...A long-lived thunderstorm cluster is moving northeastward across parts of eastern MD/VA early this evening, in association with a strong midlevel shortwave trough and 1000 mb surface low moving across the Mid Atlantic region. The northern portion of this cluster appears to be outpacing the northward return of modest surface-based instability, but increasing elevated moisture and buoyancy will help to maintain the cluster as it approaches DE and southern NJ. MUCAPE increasing to near/above 500 J/kg and strong effective shear will continue to support organized convection. Small to marginally severe hail will continue to be possible with both the ongoing cluster and with elevated storms developing ahead of the cluster, due to cold temperatures aloft (below -20C at 500 mb) associated with the shortwave trough. Increasing low-level stability may tend to limit the severe-wind threat with northeastward extent, though locally strong/damaging gusts may accompany the more organized convective elements, especially from southern NJ into the Delmarva. A brief tornado also cannot be ruled out where convection remains near-surface-based, especially near the Delmarva where the southern portion of the ongoing cluster will intercept modestly increasing MLCAPE. ..Dean/Bunting.. 12/31/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OKX...PHI...AKQ...LWX... LAT...LON 39257669 39757580 40507452 40847379 40367355 38947450 38007522 37857582 37827611 37807644 37847684 38097676 38687625 39257669 NNNN