Photo of a volcanic eruption

London VAAC Quantitative Volcanic Ash charts

In accordance with ICAO Annex 3, Amendment 82 VAAC London will provide operational QVA forecasts from 27 November 2025 and these will be made available via a VAAC London QVA API information service. These charts are currently provided for test and evaluation purposes (not for operational use) until the introduction of the operational service.

Quantitative Volcanic Ash charts (QVA) are produced in accordance with International Civil Aviation Organization (ICAO) Annex 3 requirements and are provided as well as the London Volcanic Ash Advisory Graphics (VAG) and Advisories (VAA). The lowest QVA threshold (0.2 mg/m³) matches to the areas depicted in the VAA and VAG. Both expected ash concentration and probabilistic forecast information is provided in the chart viewer below for eruptions occurring in the London Volcanic Ash Advisory Centre (VAAC) area of responsibility.

For more information on QVA and to access the API, click here. To access the API, click here.

Charts will only be available during an eruption or when tests and exercises are carried out.

Charts are only provided during an eruption, please check back later.

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