Some of the most dramatic weather events – including spring thaws, sea ice movements and the strong winds and high seas associated with severe winter cyclones – occur in the polar regions, and being able to forecast these events more accurately is crucial for mitigating their impact on local communities, fisheries, wildlife, energy production and transport. Using satellite data, this 15-nation project will help design the next generation of observing networks that are needed to improve our ability to forecast “high impact” weather events in polar regions.