Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
850 ACUS48 KWNS 300900 SWOD48 SPC AC 300859 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Fri Oct 30 2026 Valid 021200Z - 071200Z ...DISCUSSION... A large positive-tilt upper trough will move into the Plains on Monday/D4, with a surface low moving from the central Plains into the Upper MS Valley. A substantial low-level moisture plume with mid 60s F dewpoints will spread north ahead of the developing low and cold front, aided by 40+ kt south/southwest 850 mb winds. The main severe threat should develop during the afternoon along the cold front, where MUCAPE on the order of 1000 J/kg will be likely. Effective deep-layer shear will be near 50 kt, with sufficient low-level turning with height to support both supercells and linear structures late. Damaging winds and perhaps a couple tornadoes will be possible, with sporadic large hail as well. By Tue/D5, the trough is forecast to become more amplified, with more of a meridional flow pattern aloft spreading across the MS Valley. Substantial rain and thunderstorms are likely along the cold front and elongated surface trough. There is some potential for damaging winds/bows from eastern TX into AR, LA, and MS, but substantial uncertainty exists given marginal instability and widespread clouds/precip. This system will generally swing eastward across the southeastern states from Wed/D6 into Thu/D7, with at least low-end potential over some of the Gulf Coast states. ..Jewell.. 10/30/2026