Meteorological Collaborative Decision Making (MET CDM) is the process of considering aviation-related weather criteria contained in weather forecasts to assess the potential impact on the arrival rates used in Air Traffic Flow Management (ATFM). This process aims to optimise runway capacity by closing the gap between planned and actual arrival rates which will provide for greater predictability for daily operational planning by airlines. The MET CDM Program focuses on the Terminal Movement Area during the pre-tactical timeframe, specifically the day before operations at airports where a Ground Delay Program (GDP) is run.

Why do we do MET CDM?

Historically, GDP rates were determined by weather products that were not designed to support ATFM, for example, the Terminal Area Forecast (TAF). By enhancing the forecast information considered during pre-tactical planning, the gap between planned and actual arrival rates is reduced.

The MET CDM process includes weather information from the TAF and other products, as well as key expertise from NCCMET, Regional Area Forecasters and AVMETs. The MET CDM product is finalised following consultation with the CDM officer, Terminal Area Coordinator (TAC)/Traffic Manager (TM) and ATM Director to ensure the arrival rates planned are those which best suit the enhanced forecast and any other operational restrictions.

MET CDM has been identified as a priority by airlines, and forms part of the ICAO Global Air Navigation Plan.

What are the benefits of MET CDM?

The benefits of MET CDM include the following:

  • Using enhanced weather forecast information to determine pre-tactical arrival rates that will better suit the weather conditions on the day. This results in fewer GDP revisions, less wasted capacity and less restriction where not required
  • Greater predictability between planned arrival rates the day before operations and the actual arrival rates on the day, which will provide a better basis for planning the day’s operations.
  • Collaboration between meteorological experts across stakeholders has built understanding and consensus on the aviation implications of forecasting.
  • The process and business rules have more flexibility and responsiveness in regards to setting arrival rates to maximise runway throughput in consideration of weather constraints.

Updates and further information

This page summarises information provided to industry in various forms. Details may change after the time of issue. Current operational information will be provided appropriately through standard operational briefing processes such as NOTAM, AIP Supplements, AIC and NCC briefings.

For operational enquiries, contact the Airservices Network Coordination Centre on 1800 020 626 or

Alternatively, contact our Aviation Relations team at