NOUS41 KWBC 301155 



Technical Implementation Notice 15-51

National Weather Service Headquarters Washington DC

750 AM EDT Fri Oct 30 2015


To:     Subscribers:

        -Family of Services

        -NOAA Weather Wire Service

        -Emergency Managers Weather Information Network


        -Other NWS Partners, Users and Employees


From:    Tim McClung

         Portfolio Manager

         Office of Science and Technology Integration


Subject: Changes to Ensemble Kernel Density MOS (EKDMOS)

         effective December 15, 2015


Effective on or about Tuesday, December 15, 2015, beginning with

the 1200 Coordinated Universal Time (UTC) run, the NWS

Meteorological Development Laboratory will make changes to the

output mask used for Ensemble Kernel Density Model Output

Statistics (EKDMOS). 


This change will expand the output mask for the 2.5-km CONUS

grid northward from its current National Digital Forecast

Database (NDFD) extent to include most of the Northwest River

Forecast Center basin and a buffer of 170 km elsewhere along the

border with Canada; however the guidance will contain a cut-off

at the northern extent of the 2.5-km CONUS grid.


The full northward expansion of the EKDMOS grid will not be

disseminated until AWIPS systems are configured to display the

larger grid, which is anticipated to occur early next year.

Users will see a small increase in the GRIB2 file sizes in the

full northward expansion of the 2.5-km CONUS grid (generally

less than 10 percent) and in the cut-off grids (generally less

than 5 percent).


Users can download the cut-off EKDMOS guidance for the expanded

domain from the NWS ftp server at:


Users can view Gridded EKDMOS guidance for the expanded CONUS

domain at the following link (this page is not operationally

supported and guidance may not be current):


or download the parallel data here:


For questions regarding this change to EKDMOS guidance, contact:


  John Wagner

  MDL/Silver Spring, Maryland



  Matthew Peroutka

  MDL/Silver Spring, Maryland



For questions related to the data flow, please contact:

  Carissa Klemmer

  NCEP Central Operations Dataflow Team



Links to EKDMOS products and descriptions are online at:



NWS national Technical Implementation Notices are online at: