Source: wwwt.emc.ncep.noaa.gov
Topic: Production & Operations Management
Sort Desciption: MEMORANDUM FOR: NCEP Model Implementation Scientific Review Team FROM: John H. Ward Chief Production Management Branch SUBJECT: Proposed Addition of Six WRF Members to Short Range Ensemble Forecast ...
Content Inside: MEMORANDUM FOR: NCEP Model Implementation Scientific Review Team FROM: John H. Ward Chief Production Management Branch SUBJECT: Proposed Addition of Six WRF Members to Short Range Ensemble Forecast System (SREF) The Environmental Modeling Center (EMC) has proposed adding six additional Weather Research and Forecast model (WRF) runs to the Short Range Ensemble Forecast System (SREF). These six members will be added to the current fifteen member SREF system with forecasts for all 21 members out to 87 forecast hours. WRF membership will be composed of both the WRF-Non Hydrostatic Model (WRF-NMM) and WRF-Advanced Research WRF (WRF-ARW) cores with both NMM and ARW physics suites and one control and one breeding pair for each core and physics configuration. Proposed Changes The six new WRF members will be run to cover North America. However the WRF can currently not be initialized with North American Mesoscale (NAM) Data Assimilation System (NDAS) raw restart files since the WRF SI can only read in pressure grid files. Therefore all runs will be initialized with Global Forecast System (GFS) pressure grid files. The physics configurations of both WRF are detailed below. In addition to the six new WRF member runs the following fields will be added to the SREF ensemble file outputs: Instantaneous precipitation rate * Surface visibility * Surface wind * Surface Albedo * Skin Temperature The initial and breeding condition configurations for the new WRF members are outlined in the table below: Core Physics suite Breeding Initial conditions/LBC LSM init process NMMV2 NMM Ctl p1n1 GFS (T382) deg pressure file /MREF ensemble pair 5 Truncated from NDAS-12 km land states to 32 km ARWV2 NCAR Ctl p1n1 GFS deg pressure files / MREF ensemble pair 1 Truncated NDAS-12 initial states to 44 km The details of the physics suites used for each WRF core are summarized below: Suit e LSM Sfc Layer PBL Conv . Para m Microphysic s Radiation SW/LW NMM NOAH+ 4 soil lay ...
