AMC1 MET.TR.225(c)(7)(ii) Forecasts for landing

• ED Decision 2017/001/R found in: ATM/ANS Provision of Services (2017/373) (Feb 2023)

AMC1 MET.TR.225(c)(7)(ii) Forecasts for landing ED Decision 2017/001/R USE OF CHANGE GROUPS — BECMG (a)       When the change is forecast to begin and end wholly within the trend forecast period, the beginning and end of the change should be indicated by using the abbreviations ‘FM’ and ‘TL’, respectively, with their associated time groups. (b)       When the change is forecast to commence at the beginning of the trend forecast period but be completed before the end of that period, the abbreviation ‘FM’ and its associated time group should be omitted and only ‘TL’ and its associated time group should be used. (c)       When the change is forecast to begin during the trend forecast period and be completed at the end of that period, the abbreviation ‘TL’ and its associated time group should be omitted and only ‘FM’ and its associated time group should be used. (d)       When the change is forecast to occur at a specified time during the trend forecast period, the abbreviation ‘AT’ followed by its associated time group should be used. (e)       When the change is forecast to commence at the beginning of the trend forecast period and be completed by the end of that period, or when the change is forecast to occur within the trend forecast period but the time is uncertain, the abbreviations ‘FM’, ‘TL’ or ‘AT’ and their associated time groups should be omitted and the change indicator ‘BECMG’ should be used alone. AMC1 MET.TR.225(c)(7)(ii) Forecasts for landing ED Decision 2017/001/R USE OF CHANGE GROUPS — BECMG (a) When the change is forecast to begin and end wholly within the trend forecast period, the beginning and end of the change should be indicated by using the abbreviations ‘FM’ and ‘TL’, respectively, with their associated time groups. (b) When the change is forecast to commence at the beginning of the trend forecast period but be completed before the end of that period, the abbreviation ‘FM’ and its associated time group should be omitted and only ‘TL’ and its associated time group should be used. (c) When the change is forecast to begin during the trend forecast period and be completed at the end of that period, the abbreviation ‘TL’ and its associated time group should be omitted and only ‘FM’ and its associated time group should be used. (d) When the change is forecast to occur at a specified time during the trend forecast period, the abbreviation ‘AT’ followed by its associated time group should be used. (e) When the change is forecast to commence at the beginning of the trend forecast period and be completed by the end of that period, or when the change is forecast to occur within the trend forecast period but the time is uncertain, the abbreviations ‘FM’, ‘TL’ or ‘AT’ and their associated time groups should be omitted and the change indicator ‘BECMG’ should be used alone.