As part of its responsibilities as the London Volcanic Ash Advisory Centre (VAAC) the Met Office is required to provide services related to volcanic ash as defined in ICAO Annex 3 Meteorological Service for International Air Navigation, and from 27 November 2025 ICAO Doc 10157 PANS-MET – Procedures for Air Navigation Services – Meteorology
The requirement to provide Quantitative Volcanic Ash Forecasts (QVA) is introduced with Amendment 82 to Annex 3, applicable 27 November 2025.