Complex sentence: The cold snap had been forecast and British Rail claimed to be ready for the coming snow but the snow that fell that winter was unusually soft and powdery, finding its way into electrical systems and causing short circuits and traction motor damage.
Split into simpler sentences: The cold snap had been forecast and British Rail claimed to be ready for the coming snow. However, the snow that fell that winter was unusually soft and powdery, finding its way into electrical systems and causing short circuits and traction motor damage.