SADIS WAFS Gridded Data service 1.0.0


The SADIS World Area Forecast Service (WAFS) Gridded Data service (the Service) supplies tiles of meteorological gridded 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.

The Service 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 Service is provided in accordance with ICAO Annex 3 – Meteorological Service for International Air Navigation and, from November 2025, the PANS-MET – Procedures for Air Navigation Services – Meteorology (Doc 10157).

The data sets include wind (u, v), temperature, relative humidity, geopotential height, max wind (u,v and height) and tropopause (height and temperature) from both WAFC London and WAFC Washington, and the harmonised WAFS icing severity, cumulonimbus and turbulence severity data sets.

  • 0.25-degree horizontal resolution data sets are available for all parameters, and the forecast extends 48 hours for the icing, cumulonimbus, and turbulence data sets, and either 66 or 120 hours for the rest.
  • Data is provided in flight levels at 1000ft vertical intervals between the following ranges: FL050 to FL600 for wind/temperature/geopotential; FL050 to FL180 for relative humidity; FL050 to FL400 for icing severity; and FL100 to FL450 for turbulence severity.
  • A subset of data is also available at a 1.25-degree horizontal resolution for wind (u,v), temperature, relative humidity, geopotential height, max wind (u,v and height), and tropopause (height and temperature) with a limited set of vertical levels out to 36 hours. This data is provided for users who struggle to use the higher resolution data set.
  • All forecast data is provided in GRIB2 format.

The Service organises the WAFS data sets into collections that allow users to request data for specific parameters, tiles and forecast timesteps. Global coverage “tiles” as well as 8 regional tiles are available for a range of forecast timesteps, and a new set of data is published every 6 hours.

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 APIs also include:


In the event of operational issues, 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 WAFS gridded data sets for existing qualified users to download until its retirement in 2028.


Available from March 19, 2024.

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 based on gridded forecast data.
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
Tue, 03/19/2024 - 18:14
Schema version