NOUS41 KWBC 112004



Technical Implementation Notice 12-21

National Weather Service Headquarters Washington DC

405 PM EDT Wed Apr 10 2012


To:       National Weather Service Offices

          Federal Aviation Administration Customers

          Family of Services Subscribers

          Other Customers of NWS Aviation Forecasts


From:     Cynthia Abelman

          Chief, Aviation Services Branch


Subject:  Terminal Radar Approach Control (TRACON) Approach

          and Departure Gate Forecast for Convection


Effective Tuesday, May 22, 2012 at 1000 Coordinated Universal Time (UTC) all Center Weather Service Units (CWSUs) that produce a TRACON Approach and Departure Gate Forecast for Convection will issue them in accordance to NWSI 10-803, Section 7.5. This change was made to standardize the forecast format, issuance time, colors used, and terminology. These changes are clearly explained in NWSI 10-803. The products can be found online at:


For more information, please contact:


    Cyndie Abelman

    Chief, Aviation Services Branch

    National Weather Service Headquarters

    Silver Spring, Maryland, 20910

    301-713-1726 X140


National NWS Technical Implementation Notices are online: