The characteristics of intermediate layers formed by zonal and meridional winds and those containing significant metallic ion concentrations are examined. Also investigated, in addition to layers, are differences in the ionization background and their effect on layer development. Calculations show that both meridional and zonal winds may contribute to layer formation and that in combination, these wind systems may create multiple layers or even single layers lying between regions of significant wind shear. Metallic ions, if present in the valley region, will be transported into any layer formed and cause the enhancements to assume altitude profiles that are significantly different from those expected when layers are populated solely by molecular ions. ¿ American Geophysical Union 1995