The Cylc Suite Engine

Weather and related environmental forecasting using computer modelling is a complex process, made up of many interdependent tasks which can, should any of them break down, cause significant problems and delays. 

In answer to this, NIWA developed Cylc: world-leading software which helps users to better manage the dependencies of these tasks and improve overall efficiency.

In 2014, the UK Met Office switched over to using Cylc to run and manage all the operational systems for its Unified Model, a global forecasting system (including the Exeter arm of the World Aviation Forecasting System used for all airline flight briefings), regional and commercial forecasting, archiving and product generation.

Cylc is a now a general purpose workflow engine that orchestrates cycling workflows very efficiently. Even though it was designed for production weather, climate, and environmental forecasting systems, it is not specialised to those domains and is completely agnostic to the applications it manages.

Cylc is an Open Source collaboration involving NIWA, UK Met Office, and others. It is available under the GPL v3 license.

Visit the Cylc website at for more information.