Research-level WRF module versions module_bl_mynn_thaxton_xxx.F are modified versions of the WRF MYNN code to improve performance over complex terrain.
v01: - Lines 700: 706: Add conditional for bl_mynn_mixlength.GE.10 to enhance turbulent length scale, elt, across all domains (No flow conditional). alp1 = ( bl_mynn_mixlength-100.0 )/100.0
In MYNN code: zi = PBL height - how is this computed? ; transition layer = h1
See: line 884 el(k) = el(k)*(1.-wt) + elf * wt
See: line 859 wt=.5*TANH((zwk - (zi2+h1))/h2) + .5