Why do wind, snow, freezing and rain weather lead to frequent local power grid failures and widespread power outages?

My understanding is that although it is cold and snowy in the north, it is very dry and has no rain. In the south, there is always sleet or freezing rain, forming thick ice on electrical equipment. The weight of the ice exceeds design standards, causing high-voltage hub lines that transmit power over long distances, often through mountainous areas, to trip or even collapse towers.

The dance caused by the ice-covered lines also caused great harm to the operation. In addition, the cold weather lasted for too long, and the workload was too heavy. The staff worked day and night (melting ice, patrolling the lines) (Ah, even repairing equipment) cannot eliminate even one ten thousandth of the impact of weather!