World Meteorological Organization

1. Requirements for new versions of IWXXM are driven by
   1. amendments to ICAO Annex 3/PANS-MET or relevant documents
   2. bugs discovered which are considered to have significant impact to message creation
2. TT-AvData after seeking views from ICAO WG-MIE addresses these requirements by updating the IWXXM information model and schemas
3. A public consultation will be conducted with the following actions
   1. prepare a Release Candidate (RC) based on the revised IWXXM schemas
   2. post the RC at https://schemas.wmo.int/iwxxm/
   3. send announcement to tt-avdata@groups.wmo.int with a deadline for end of review
   4. email notification to chairs of ICAO WG-MIE, ICAO Secretariat and WMO Secretariat colleagues who support services for aviation on the conduction of public consultation
   5. feedback is taken into consideration as needed
4. Subject to the outcome of the public consultation further public consultations and RCs may be required
5. When the revised IWXXM information model and schemas are ready for WMO endorsement
   1. prepare a RC based on the revised IWXXM schemas
   2. post RC at https://schemas.wmo.int/iwxxm
   3. draft amendments to Manual on Codes (WMO-No. 306), Volume I.3 in a new section on IWXXM
   4. Request Chair of SC-IMT to approve
   5. email the WMO National Focal Points (FP) for Data and Representation Matters with a two month window for review
   6. email notification to chairs of ICAO WG-MIE, ICAO Secretariat and WMO Secretariat colleagues who support services for aviation
   7. FP reviews are taken into consideration as needed
   8. request President of INFCOM to approve the amendments
   9. request President of WMO to approve the amendments
6. When the amendments have been approved
   1. prepare a final release based on the approved IWXXM schemas
   2. post final release at https://schemas.wmo.int/iwxxm
   3. post IWXXM codes to the WMO Codes Registry
   4. send amendments in Manual on Codes (WMO-No. 306), Volume I.3 to WMO publication department
   5. publish an announcement in the WMO Operational Newsletter
   6. send an announcement to tt-avdata@groups.wmo.int
   7. email chairs of ICAO WG-MIE, ICAO Secretariat and WMO Secretariat colleagues who support services for aviation on the publication of the new version of IWXXM and amendments to WMO-No. 306

(page last updated: 2024-09-24)