example of low-level thermodynamic environment that may support "landspout" tornadoes:

   Several non-mesocyclone tornadoes along a well-defined NE-SW boundary were associated with this estimated profile.

Note here the very steep lapse rate in the bottom 2 km that approximates the dry-adiabatic lapse rate as a result of strong afternoon heating in low-levels.  While this is not unusual in late spring and summer, it is less common to find a deep well-mixed moist layer combined with this step low-level lape rate and little if any CIN.  Theoretically, this environment should allow parcels with developing storms along a well-defined convergence boundary to rise/stretch rapidly in the lowest 2-3 km, without excessive entrainment and "mixing-out", contributing to the potential for non-mesocyclone "landspout" tornadoes.