Scorching Plains Trough Sparks 80 MPH Severe Gust Threat in NE/SD — SevereWX

A surface trough slicing through the central Plains is fueling a volatile setup for severe thunderstorms this evening in parts of western and central Nebraska into southeast South Dakota.

Afternoon cumulus towers are bubbling up near the trough, where temperatures have soared above 100°F. Plentiful low-level moisture combined with steep lapse rates is yielding MLCAPE values from 2000 J/kg in west-central Nebraska to over 4000 J/kg farther north into southeast SD. Veering winds and 30-40 kt effective shear provide a conditionally solid foundation for storm organization.

While large-scale lift is weak—leaving storm initiation timing uncertain—forecasters expect at least isolated development by early evening along the boundary. The primary hazard will be damaging straight-line winds of 60-80 mph in this steep low-level lapse rate environment. A supercell or two could mix in 1-1.75 inch hail.

SPC's Mesoscale Discussion 1747 highlights a 60% chance of watch issuance to cover these risks through 10 PM CDT. Peak gusts could hit 65-80 mph, posing dangers to those outdoors or in exposed areas.

Stay prepared: Monitor radar closely, secure outdoor items, and have a severe weather plan ready. Avoid travel if storms develop—downbursts can strike suddenly in this heat-fueled setup.