Determination of ice loading and tornado loading maps for transmission line design

The project aims to provide information on the risk of meteorological hazards that can cause power line disruption. Two types of hazard are being considered:

• Tornadoes: Tornadoes can cause significant damage to overhead power lines and electricity substations. We are mapping the risk posed by tornadoes in the contiguous US. We ignore both the weakest tornadoes, which are no stronger than winds associated with strong synoptic storms, and the strongest tornadoes, which are so destructive that it is not viable to design the power infrastructure to withstand them.

• Freezing rain: Freezing rain can add significant extra load on overhead transmission lines because the rain can stick to them. We are mapping the risk posed by freezing rain in the contiguous US by estimating freezing rain accumulations for specified return periods.