A modeling approach with both mesoscale and microscale capabilities is needed and proposed.

The proposed approach includes adding mesoscale and porous turbulence model terms and transforming the vertical coordinates.

The approach was successfully implemented using a commercial CFD package for studying urban heat island circulation (UHIC).

The predicted quantities agree well with existing data in the literature obtained from both simulations and experiments.

Our predicted results reveal the effects of the different heat fluxes and urban height in terms of UHIC characteristics.