ZCZC SPCSWOMCD ALL ACUS11 KWNS 082015 SPC MCD 082015 NYZ000-NJZ000-PAZ000-MDZ000-082215- Mesoscale Discussion 1715 NWS Storm Prediction Center Norman OK 0315 PM CDT Wed Sep 08 2021 Areas affected...Eastern Pennsylvania...northwest New Jersey...southeastern New York Concerning...Severe potential...Watch possible Valid 082015Z - 082215Z Probability of Watch Issuance...40 percent SUMMARY...The threat for severe weather will gradually increase into early evening across parts of the Mid-Atlantic. Damaging wind gusts and isolated large hail are the main concerns. A conditional tornado threat exists in eastern Pennsylvania and southeastern New York. Timing and coverage of severe storms is uncertain. Trends will be monitored for a possible watch. DISCUSSION...The 18Z observed Albany sounding showed relatively weak capping, but signs of subsidence aloft. This general profile seems to capture what is being observed on visible satellite across the Mid-Atlantic. Areas of cumulus, particularly within eastern Pennsylvania where temperatures are in the mid 80s F, have shown a gradual increase in depth. The subsidence aloft is likely limiting vertical development. With time, and additional mid-level cooling, storms should be able to initiate in the warm sector. Farther west, warm conveyor belt precipitation has generally been weak with only small embedded convective elements. A gradual increase in convective character may occur as this activity encounters more buoyant air. The greatest severe potential likely exists with any warm sector storms that can develop. Damaging winds, isolated large hail, and perhaps a tornado could occur. Eastern Pennsylvania into southeastern New York would be the favored zone for low-level rotation given slightly backed surface winds. Storms within the warm conveyor belt should exhibit a more linear storm mode and pose primarily a damaging wind gust risk. There is some uncertainty as to when storms will intensify this afternoon. Much of the guidance suggest it may not be until around or after 8 PM EDT. With potentially unfavorable timing diurnally, trends will have to continue to be monitored for a possible watch later this afternoon. ..Wendt/Hart.. 09/08/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OKX...ALY...PHI...BGM...CTP...LWX... LAT...LON 39887582 39527639 39527675 39657708 39877720 40147709 40387698 40697677 40887660 40987650 41707602 42567512 42937433 42527370 41857365 40957458 39887582 NNNN