POPLAR BLUFF, Missouri — The severe weather focus is sharpening on southeastern Missouri tonight, where tornado-warned storms are ongoing in an environment of favorable shear vectors and potent thermodynamics that could produce a few tornadoes in the deep forest of southeast Missouri. Meanwhile, the Arkansas warm sector — largely untouched by convection through the evening — remains a question mark for overnight storm development as a jet max across northern Texas may extend lift southward and initiate new storms across a relatively fresh atmospheric environment.
What Is Happening in Southeast Missouri Right Now
The 300mb analysis shows the upper-level setup clearly. The orange oval marks the region of active storm development across southern Missouri, where lift associated with a jet streak is supporting the tornado-warned cells currently tracked by meteorologists. The 9300 meter height contour and the divergence signature in the magenta contours confirm upper-level support for sustained convection across this corridor.
The favorable shear vectors in southeast Missouri — where winds are veering with height in a configuration that supports rotating updrafts — combined with potent thermodynamics in the warm sector are the ingredients keeping the tornado threat active well into the overnight hours. The deep forest terrain of southeast Missouri presents an additional concern: tornadoes in heavily forested, rural areas are harder to detect visually, harder to survey after the fact and more dangerous for residents in isolated communities with limited shelter access.
The Arkansas Problem — Zero Divergence, No Lift
The complicating factor for Arkansas is the absence of the atmospheric support mechanism that is keeping southeast Missouri active. At 01Z, there is zero divergence or difluence over most of Arkansas — meaning the upper-level dynamics that help sustain thunderstorm updrafts by pulling air upward are essentially absent across the state. Without divergence aloft, updrafts struggle to maintain themselves and storm development stalls or dissipates…