Widespread severe thunderstorms are expected to develop on Tuesday from Texas to Wisconsin, unleashing damaging winds, torrential rain, hail, and the threat of tornadoes in some regions.
“An upper-level trough will dig southeastward from the northern Plains into the central Plains today. An associated mid-level jet will dive southeastward into the central Plains. The leading edge of the stronger mid-level flow associated with the jet will overspread a corridor of maximized low-level moisture located from northeast Texas north-northeastward into the Ozarks,” the National Weather Service (NWS) Storm Prediction Center reported on Tuesday morning.
“Moisture advection ahead of the system, will increase surface dewpoints into the 60s F across most of Oklahoma, Arkansas and Missouri by afternoon. In response to surface heating, the moisture will contribute to moderate destabilization with MLCAPE values reaching the 2000 to 4000 J/kg range across parts of the moist sector. Thunderstorms are forecast to first initiate to the south of a surface low on the northern edge of the moist airmass in eastern Iowa around midday.”
NWS said a “squall line” will develop by evening as the system moves “southward across southwest Missouri, western Arkansas and east-central Oklahoma.”
“Wind damage will be likely along the leading edge of the squall line. Wind gusts over 65 kt will be possible ahead of the faster moving parts of the squall line. A few tornadoes may also occur with rotating cells embedded in the line. A widespread wind damage threat should continue into parts of north-central and northeast Texas during the mid to late evening before a gradual weakening takes place due to overnight decreasing instability.”