NOUS41 KWBC 251253



Technical Implementation Notice 14-31

National Weather Service Headquarters Washington DC

853 AM EDT Fri Jul 25 2014


To:      Subscribers:

         -Family of Services

         -NOAA Weather Wire Service

         -Emergency Managers Weather Information Network


         Other NWS Partners and NWS Employees


From:    Tim McClung

         Science Plans Branch Chief

         Office of Science and Technology


Subject: Extra-Tropical Storm Surge (ETSS) enhancements:

         Effective August 26, 2014


On Tuesday, August 26, 2014, beginning with the 1200 Universal

Coordinated Time (UTC) cycle, the Extra-Tropical Storm Surge

(ETSS) model will reflect three changes.


1. Use 0.5 degree gridded wind input from the Global Forecast

   System model instead of 1 degree

2. Use a corrected mask for merging data over the Bering Sea

3. Begin generating 2.5 km National Digital Forecast Database

   (NDFD) CONUS GRIB2 files and 3 km NDFD Alaska GRIB2 files


For the NWS FTP server, the 2.5 km CONUS products will be

available in the National Digital Guidance Database (NDGD):



NWS will discontinue the 5 km CONUS products in that directory:

- grib2.mdlsurgegrid.00con

- grib2.mdlsurgegrid.06con

- grib2.mdlsurgegrid.12con

- grib2.mdlsurgegrid.18con


The 3 km Alaska products will be available here:


NWS will discontinue the 6 km Alaska products:

- grib2.mdlsurgegrid.00ala

- grib2.mdlsurgegrid.06ala

- grib2.mdlsurgegrid.12ala

- grib2.mdlsurgegrid.18ala


For the NCEP FTP server the new products will be available here:


where YYYY is the current year, MM is the current month, DD is

the current day, and HH is the current hour.  They will have

names of: grib2.mdlsurgegrid.2.5km.HHcon for CONUS and

grib2.mdlsurgegrid.3km.HHala for Alaska.


The new products are already available in parallel at:


NWS will discontinue the 5 km CONUS product

(grib2.mdlsurgegrid.HHcon) and the 6 km Alaska product



For the Satellite Broadcast Network and NOAAPORT, NWS will

provide both the original and new products.  The new products

will have WMO headers of:


     WMO Heading         Region


     MHU... KNHC         NDFD CONUS 2.5 km grid

     MHR... KNHC         NDFD Alaska 3 km grid


The ... in the WMO heading will be replaced by DHH, where D is

the day of the forecast.  A=Day 0, B=Day 1, ... F=Day 5 and HH is

the hour of day when the forecast is valid. A full chart of the

header combinations per forecast cycle is available here:


Once AWIPS is ready, NWS will discontinue the old products with

WMO heading of LHU... KNHC and LHR... KNHC.


If you have any questions about these changes and additions to

the ETSS guidance, please contact:


     Arthur Taylor & Huiqing Liu

     Meteorological Development Laboratory

     Phone: 301-713-1613 X163, 301-713-1613 X162



NWS Technical Implementation Notices are online at: