entire world. Volcanic ash advisories When an ash cloud is detected, the VAAC will gather all the available observations, using them in conjunction with both ash dispersion and numerical weather models, to forecast the path and evolution of the ash cloud. They will then issue a volcanic ash advisory (VAA) to aviation and meteorological offices as stated within the Handbook on the IAVW. This will be in the format of a text based message, with a corresponding graphic. Within the advisory the following information will be provided: the name of the volcano, the country/region, location and summit elevation of the volcano, the source of the information, e.g. satellite or pilot observation, details of the eruption including time of day in UTC and date of the eruption, details of the ash cloud including the vertical extent (in flight levels) and horizontal extent, detail on the current movement of the ash cloud, forecast movement and evolution of the cloud for 6, 12 and 18 hours ahead following the time of the advisory, any remarks by the VAAC and finally the next update time. See also Mount Pelée Peléan eruption Plinian eruption References External links WMO Aeronautical Meteorology Programme WMO Aeronautical Meteorology Programme (New) The Meteorology Panel (METP) Volcanology Aviation risks Aviation meteorology Volcano monitoring