Mesoscale Discussion 1588 NWS Storm Prediction Center Norman OK 1025 AM CDT Mon Jul 25 2022 Areas affected...far eastern PA and northern NJ into southern New England Concerning...Severe potential...Watch likely Valid 251525Z - 251700Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms coverage and intensity is expected to increase over the next 1-2 hours from eastern PA and northern NJ into southern New England. Damaging gusts and hail are the main hazards expected with this activity. DISCUSSION...Convection is rapidly increasing in intensity late this morning. Broken cloudiness has allowed temperatures to warm into the 80s amid 70s surface dewpoints. This is aiding in moderate instability across the region amid strong southwesterly vertical shear ahead of an eastward-advancing cold front. Forecast soundings and regional VWP data suggest wind profiles favorable for supercells and line segments. Steepening low-level lapse rates and strengthening 0-3 km MLCAPE will support strong gusts with this activity. Meanwhile, modest midlevel lapse rates and elongated hodographs above 3 km may support sporadic large hail with stronger semi-discrete cells. Favorable low-level shear and somewhat small, but favorably curved low-level hodographs also will support a risk for a tornado given a very moist boundary-layer and increasing low-level vorticity along/just ahead of the surface cold front, though damaging gusts are expected to be the main hazard. Given recent increase in convective intensity and expected increase in thunderstorm coverage with time into early afternoon, a watch will likely be needed in the next hour or so. ..Leitman/Guyer.. 07/25/2022
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