Freezing rain falls on the ground and creates a dangerous glaze of ice on surfaces including sidewalks, driveway and roads and creates hazardous travel and driving conditions.
The freezing rain that coats the road makes the roads very slippery and can cause a vehicle to slide off the road or spin out and could cause the vehicle to crash.
Freezing rain can also coat power lines and cause power lines to sag and even coat trees and cause the trees to break and cause power outages.
When super cooled rain falls and freezes on contact with any subfreezing surface, it forms a layer of ice which makes roads, sidewalks, driveways and other surfaces very slippery.
The ice accumulation from freezing rain can also weigh tree branches down as well as power lines, telephone lines etc and cause them to eventually snap and fall due to all the weight and result in blocked roadways and power outages.
You should put some salt down before freezing rain to help prevent the rain from freezing on the surfaces.
Roads are salted with road salt before the rain starts to freeze on the surface.
Salt is sprayed on icy roads in the winter to lower the freezing temperature or freezing point of the ice.
Salt sprayed on the road prevents ice from forming in colder temperatures on the road and salt that is sprayed on roads when temperatures are at or below 32 F can help to melt the icy patches of ice on the roads.
So if there's precipitation (snow, sleet, or freezing rain) and the ground is 32 degrees or colder, ice will form on streets and other surfaces.
So, why use salt on roads and other surfaces?
It's simple – salt lowers the freezing point of water, which prevents ice from forming.
Just like when you put salt on your sidewalk or driveway or porch etc it melts the ice and prevents other ice from forming.
Road salt, or sodium chloride, works by lowering the freezing point of water, causing ice to melt even when the temperature is below water's normal freezing point of 32 degrees.
When salt is applied, it dissolves into separate sodium and chloride ions that disrupt the bonds between water molecules.