NOUS41 KWBC 281322 CCA



Technical Implementation Notice 12-50: Corrected

National Weather Service Headquarters Washington DC

822 AM EST Wed Nov 28 2012


To:       Subscribers:

          - Family of Services

          - NOAA Weather Wire Service

          - Emergency Managers Weather Information Network

          - NOAAPORT

          Other NWS Partners and NWS employees


From:     Eli Jacks

          Chief, Fire and Public Weather Services Branch


Subject:  Corrected: Two Operational Fire Weather Elements to be

          Added to the National Digital Forecast Database for

          the United States, including Hawaii, Guam and

          Puerto Rico, Effective November 27, 2012


Corrected to remove the reference to Alaska Region (AR). The AR 

Daily Maximum/Minimum Relative Humidity elements in the National

Digital Forecast Database will remain experimental until further



Effective Tuesday, November 27, 2012, at 1400 Coordinated

Universal Time (UTC), the National Digital Forecast Database

(NDFD) will add Daily Maximum and Minimum Relative Humidity (RH)

operationally for the United States, CONUS and OCONUS, including

Hawaii, Guam and Puerto Rico. These elements are generated from

computation of the existing hourly dew point and hourly

temperature grids.


These two fire weather elements will be in the NDFD for the valid

times shown:


- Maximum Relative Humidity (Days 1-7)

- Minimum Relative Humidity (Days 1-7)


More details regarding these elements are available in the

Product Description Document (PDD) in the online catalog of NWS

products and services.


With this implementation, these forecasts will be available from

NDFD in the standard methods:


- Gridded Binary version 2 (GRIB2) files via Hypertext Transfer

  Protocol (HTTP) and File Transfer Protocol (FTP)

- eXtensible Markup Language (XML) via Simple Object Access

  Protocol (SOAP)

- Graphics via Web browser:


Users who pull NDFD elements in GRIB2 format, either via the

internet or via the Family of Services server access service, may

need to update their procedures and scripts in order to access

these elements. The GRIB2 files are online at:



Partners and users who use the NDFD in XML via Web service or the

online graphical NDFD images can use the same methods they

currently use to acquire these elements.


More information about accessing and using NDFD elements is

online at:


If November 27, 2012, is declared a critical weather day, this

implementation may be postponed. In that case, users will be

notified of that decision via an updated Technical Implementation

Notice as far in advance as possible.


For questions regarding these products, please contact:


  Heath Hockenberry

  National Fire Weather Program Manager

  NOAA/NWS Office of Climate, Water and Weather Services

  Boise, ID


For general questions regarding NDFD data, please email:


For technical questions regarding NDFD data, please contact:


  David Ruth

  Mesoscale Prediction Branch Chief

  NOAA/NWS Office of Science and Technology

  Silver Spring, Maryland


For questions regarding this notice, please contact:


  Robyn Heffernan

  Fire Weather Science and Dissemination Meteorologist

  NOAA/NWS Office of Climate, Water and Weather Services

  Boise, ID


Technical Implementation Notices specifically related to NDFD

are online at:


National Technical Implementation Notices are online at: