Severe weather outlook: Slight risk of severe thunderstorms across DE, NJ, PA

SPC AC 122000 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0200 PM CST Thu Nov 12 2026 Valid 122000Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON OVER PARTS OF CENTRAL/SOUTHERN NEW JERSEY AND FAR SOUTHEASTERN PENNSYLVANIA... ...SUMMARY... Severe thunderstorms capable of producing severe hail, a couple of tornadoes, and perhaps damaging winds remain possible across parts of southeastern Pennsylvania and southern/central New Jersey this afternoon. ...20Z Update... The primary change with this update was trimming severe-thunderstorm probabilities across parts of eastern MD and DE, as the primary severe risk will continue spreading northeastward from far southeastern PA across southern/central NJ through the afternoon -- in tandem with the eastward-moving surface low. For details on the near-term severe risk, see MCD #2452 and Tornado Watch #705. ..Weinman.. 11/12/2026 .PREV DISCUSSION... /ISSUED 1019 AM CST Thu Nov 12 2026/ ...Eastern PA/NJ/Northern DE... Latest surface analysis shows a developing surface low over northern VA. This low is expected to deepen somewhat through the day and track eastward across NJ as a potent shortwave trough moves into the region. The zone near the surface low and extending eastward along the surface warm front will be a focused region of ascent and destabilization this afternoon, with forecast soundings showing MLCAPE of 500-900 J/kg, steep lapse rates, and considerable low-level shear/helicity profiles. A consensus of morning HRRR/RRFS/REFS solutions show the development of isolated supercell storms in this focused area. The risk area is quite small, but given the consistent guidance have opted for a small SLGT risk to cover the potential threats. Hail is probably the main concern with any persistent supercell structure, but a tornado or two is also possible. Refer to MCD #2451 for further details. CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z