SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Sat Apr 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND SOUTHERN APPALACHIANS... ...SUMMARY... A wind-damage and isolated tornado threat will be possible on Sunday across parts of the Southeast. Marginally severe wind gusts will also be possible in parts of the southern Appalachians. ...Southeast/Southern Appalachians... Southwest mid-level flow is forecast across the Southeast on Sunday. A mid-level jet streak will move northeastward into the Ohio Valley, as a cold front advances eastward across the Gulf Coast states and southern Appalachians. A large MCS is expected to be ongoing near the front at the start of the period. The MCS is forecast to move slowly eastward during the day into a moist and unstable airmass. Ahead of the front, surface dewpoints will be in the mid to upper 60s F over much of the Southeast, and from the mid 50s to lower 60s F in the southern Appalachians. The unstable airmass ahead of the front is expected to gradually become more stable during the day, due to abundant cloud cover and convective outflow. In spite of this, the southern edge of the mid-level jet streak will create strong deep-layer shear, sufficient for an isolated severe threat Forecast soundings near the instability axis in eastern Alabama during the afternoon show moderate deep-layer shear, which will support storm organization. Ahead of the front, model forecasts have a 40 to 55 knot low-level jet persisting through much of the morning and afternoon. Near the low-level jet, forecast hodographs are curved with 0-3 km storm-relative helicity in the 250 to 350 m2/s2 range. For this reason, an isolated tornado threat will be possible with supercells. However, the primary storm mode is expected to remain linear. Line segments that can organize into bowing segments will have a wind-damage threat. The severe threat may persist into early evening, but should become more isolated as instability weakens across the region. Further to the north into parts of the southern Appalachians, strong deep-layer shear associated with the edge of a mid-level jet streak will support some storm organization. However, instability is forecast to be very weak, suggesting that any wind-damage threat will be marginal. ..Broyles.. 04/05/2025
