Local Models at WFO Charleston

The National Weather Service in Charleston is currently running the Weather Research Environmental Modeling System (WRF-EMS), a full featured numerical weather prediction package that incorporates two dynamic cores. The first core is the Advanced Research WRF (ARW) made available from the National Center for Atmospheric Research (NCAR), and the second is the National Center for Environmental Predictions' non-hydrostatic mesoscale model (NMM). The WRF-EMS Package allows for a wide range of configuration, physics, micro-physics, and parameterization schemes. Below is a general description of how the models are configured to run at the National Weather Service in Charleston. Both models are initialized using the NCEP North American NAM12.

Description of the WRF-ARW

The WRF-ARW is executed 8 times per day as a one-way nest. . The model is initialized by a Local Analysis and Prediction System (LAPS) in "hot start" mode. The boundaries are initialized with NCEP's North American Mesoscale (NAM) model at 15 KM resolution. Output for two domains are available, a 15KM outer domain, and a 5KM nested domain centered on West Virginia.

Domain & Run Information for the WRF-ARW:
       Primary Time Step         :  Adaptive                 Adaptive                
       Step to Output Time       :  Yes                      Yes                     
       Grid dimensions (NX x NY) :  135 x 135                136 x 136               
       Vertical Layers (NZ)      :  45                       45                      
       Grid Spacing              :  15.00km                  5.00 km                 
       Top of Model Atmosphere   :  50mb                     50mb                    
       Parent Domain             :  NA                       Domain 01               
                                 
     Model Physics                  
       Dynamics                  :  Non-Hydrostatic          Non-Hydrostatic         
       Cumulus Scheme            :  Kain-Fritsch             None                    
       Microphysics Scheme       :  Ferrier Microphysics     Ferrier Microphysics              
       PBL Scheme                :  Yonsei University        Yonsei University       
       Land Surface Scheme       :  Noah 4-Layer LSM         Noah 4-Layer LSM        
       Number Soil Layers        :  4                        4                       
       Surface Layer Physics     :  Monin-Obukhov            Monin-Obukhov           
       M-O Heat and Moisture     :  Surface Fluxes On        Surface Fluxes On       
       M-O Snow-cover Effects    :  Included                 Included                
       Long Wave Radiation       :  RRTMG Scheme             RRTMG Scheme            
       Short Wave Radiation      :  RRTMG Scheme             RRTMG Scheme            

     ARW Core Model Dynamics     
       Dynamics                  :  Non-Hydrostatic          Non-Hydrostatic         
       Gravity Wave Drag         :  Off                      Off                     
       Time-Integration Scheme   :  Runge-Kutta 3rd Order    Runge-Kutta 3rd Order   
       Diffusion Scheme          :  Simple Diffusion         Simple Diffusion        
       6th-order Diffusion       :  No 6th-Order Diffusion   No 6th-Order Diffusion  
       Eddy Coefficient Scheme   :  2D 1st Order Closure     2D 1st Order Closure    
       Damping Option            :  W-Rayleigh               W-Rayleigh              
       Damping Depth from Top    :  5 Km                     5 Km                    
       Damping Coefficient       :  0.12                     0.12                    
       W Damping                 :  W Damping On             W Damping On            
       Horiz Momentum Advection  :  5th Order                5th Order               
       Horiz Scalar Advection    :  5th Order                5th Order               
       Vert Momentum Advection   :  3rd Order                3rd Order               
       Vert Scalar Advection     :  3rd Order                3rd Order               
       Sound Time Step Ratio     :  Automatic                Automatic               
       Moisture Advection Option :  Positive-Definite        Positive-Definite       
       Scalar Advection Option   :  Positive-Definite        Positive-Definite       
       TKE Advection Option      :  Positive-Definite        Positive-Definite  

Description of the WRF-NMM

The WRF-NMM model is executed 8 times per day for a 3 hour cycle start time. The model is initialized by a Local Analysis and Prediction System (LAPS) in "hot start" mode. In addition, this domain executes with the Digital Filter Initialization (DFI) option turned on. The boundaries are initialized with NCEP's North American Mesoscale Model (NAM) at 12 KM resolution. Output from a single domain with a resolution of 5 KM is available.

Domain & Run Information for the WRF-NMM
       Primary Time Step         :  10.4 Seconds
       Grid dimensions (NX x NY) :  176 x 330
       Vertical Layers (NZ)      :  45
       Grid Spacing              :  4.96 km
       Top of Model Atmosphere   :  50mb
       Parent Domain             :  NA
     
     Digital Filter Initialization Information
       DFI Method                :  DF Launch
       DFI Filter                :  Dolph
       DFI Backstop              :  40 Minutes
       DFI Forwardstop           :  20 Minutes
       DFI Cut Off               :  20 Minutes

     Model Physics
       Dynamics                  :  Non-Hydrostatic
       Cumulus Scheme            :  None 
       Microphysics Scheme       :  Ferrier Microphysics
       PBL Scheme                :  Mellor-Yamada-Janjic
       Land Surface Scheme       :  Noah 4-Layer LSM
       Number Soil Layers        :  4
       Surface Layer Physics     :  Monin-Obukhov (Janjic)
       Long Wave Radiation       :  GFDL Long Wave Radiation
       Short Wave Radiation      :  GFDL Short Wave Radiation

     NMM Core Model Dynamics
       Dynamics                  :  Non-Hydrostatic
       Gravity Wave Drag         :  Off

       Time-Integration
                                 :  Horizontally propagating fast-waves - Forward-backward scheme
                                 :  Vertically propagating sound waves - Implicit scheme
          Horizontal             :  Adams-Bashforth
          Vertical               :  Crank-Nicholson

       Advection of T, U, and V
          Horizontal             :  Energy and entropy conserving, quadratic conservative, 2nd order
          Vertical               :  Quadratic conservative, 2nd Order

       TKE and Moisture Adv      :  Explicit, Upstream, Flux-Corrected, Positive Definite, Conservative
       Vertical Diffusion        :  Handled by PBL and Surface Layer Schemes
       Lateral Diffusion         :  Smagorinsky Non-linear Approach
       Divergence Damping        :  Horizontal component of divergence is damped