SADIS WAFS OpMet API Data service 1.0.0


The SADIS World Area Forecast Service (WAFS) OpMet API Data service supplies packaged bulletins of meteorological observations data in response to tailored API requests submitted by an end user. This data is provided under the remit of the International Civil Aviation Organisation (ICAO) and can be used to support activities related to aviation. Responses to API requests may be in the form of API codes, JSON payloads or HTTP re-directs to payloads of data.

The SADIS API is operated by the Met Office in its role as World Area Forecast Centre (WAFC) London, and is primarily available to users located in Europe, Africa, the Middle East, and Asia.

WAFS data sets can be used for:

  • Flight planning (and therefore reducing fuel burn) 
  • Reducing C02 emissions 
  • Hazard awareness and avoidance

The WAFS OPMET API data is provided in accordance with ICAO Annex 3 – Meteorological Service for International Air Navigation and the PANS-MET – Procedures for Air Navigation Services – Meteorology (Doc 10157 due for introduction in November 2025) and can comprise of METARS, TAFS, AIRMET, SIGMET, Volcanic Ash, Tropical Cyclone, Nuclear emergency messages, NOTAMs and GAMETS

  • OPMET reports in packets of 5 minutes in traditional alphanumeric code (TAC) and IWXXM data formats, for the time period between T0 and T-36hrs. Data can be requested and provisioned for the following geographical spatial areas: GLOBAL, EUR-NAT, NAM-CAR, SAM, AFI, MID, ASIA-PAC
  • Information can be requested and provisioned in .json format relating to the operation/mechanics of the API, this also includes the co-ordinates of the polygons used to describe the geographical spatial areas
  • OPMET advisory reports for GLOBAL geographic spatial areas in packets of 30 minutes in traditional alphanumeric code (TAC) and IWXXM format, for the time period between T0 and T-36hrs.
  • Notices

SADIS WAFS OPMET API Data (the service) is part of the SADIS API family of offerings developed by the Met Office, which use the Open Geospatial Consortium Environmental Data Retrieval (OGC-EDR) framework. SADIS API includes:

  • SADIS WAFS Gridded Data API

The service organises the OPMET bulletin data sets into collections that allow users to request data for specific file types, spatial coverage areas, temporal coverage and notification types (advisory reports or advisory notification reports).

In the event of critical operational issues with the SADIS API, the WIFS API operated by WAFC Washington is available for backup purposes. The SADIS and WIFS API offerings have been harmonised to make this easier. Information on the WIFS API is available here: and users will need to register separately to access it.

Furthermore, SADIS FTP also provisions OPMET bulletins for existing qualified users to download until its retirement in 2028.

Service Type
Life Cycle
Business Activity Type
Intended Consumer
Information Exchange Category
Application Message Exchange Pattern Entity
State ICAO Nationality Letters
ICAO Region
Geospatial Categorisation Description
Worldwide coverage, where available, of data sets that are disseminated internationally over the Aeronautical Fixed Service.
In-Operation Date
Met Office

The Met Office is the sole Air Navigation Service Provider (ANSP) certificated by the UK Civil Aviation Authority to provide and disseminate a range of aviation forecast products and services, in accordance with ICAO Annex 3 to the Chicago Convention, Meteorological Service for international Air Navigation.

ICAO’s Annex 3 provides the main regulatory framework against which the UK is obliged to provide meteorological services, and which the Met Office delivers Met Services against. This ensures that the UK meets its obligations to ICAO to provide safe, efficient and regular air travel.

These services fall into the following main categories:

a) UK services.

b) The World Area Forecast System (WAFS), as provided by World Area Forecast Centre (WAFC) London, in coordination with WAFC Washington.

c) SADIS (Secure Aviation Data Information Service).

d) The Volcanic Ash Advisory Centre (VAAC) London.

In addition to the ICAO Annex 3 determined services, a range of discretionary services that are determined as a requirement in the UK are also provided. Specific services such as Aviation R&D and the provision of information to NATS are examples of this.

Provider Type

To report incidents on services in operation, contact the 24/7 Weather Desk at [email protected] or +44 330 135 0000.

Revision Save Date
Wed, 05/08/2024 - 11:14
Schema version