What is UW-NMS?

UW-NMS stands for University of Wisconsin - Nonhydrostatic Modeling System.

It is a nonhydrostatic research model, used primarily to investigate the interaction of convection with mesoscale and synoptic-scale weather phenomena.

Recent studies have looked at the the role of deep moist convection and its organization on the mesoscale. The focus of recent studies includes scale interactions within tropical cyclones, organization of tropical cloud clusters, tropical cyclogenesis, polar lows, gravity waves and other mesoscale organization within wintertime baroclinic cyclones, mesoscale organization of lake effect snow storms over the Great Lakes, severe storms including super cells, multi-cells and derechos, mid-latitude mesoscale convective complexes, and large eddies in the PBL.

Some features of the model include:

• Arbitrary resolution in all directions
• Local spherical coordinate system in horizontal
• Height coordinate system with step topography using a terrain following variable grid spacing near the ground
• Multiple two-way interactive grid nesting, with moveable inner grids
• Gridscale microphysics parameterization with cloud water, rain, pristine crystals, snow, aggregate crystals, and graupel
• Modified Emanuel convective parameterization scheme
• Long/Short wave radiation parameterization with clouds
• Diffusion based on TKE prediction

More detailed information is available about these aspects of the model:

• Grid System
• Grid Nesting
• Dynamics
• Quasi-compressible Approximation
• Integral Constraints
• Thermodynamic Equations
• Thermodynamic Diagnosis
• Numerical Scheme
• Lower Boundary

Holly Hassenzahl
hcderose@wisc.edu