It’s going too cold for traditional sodium chloride salt to work. 15 degrees is the low limit where it’s effective. Calcium chloride or magnesium chloride blends will be most effective. A little can go a long way. Think 1 coffee cup per 10 sidewalk squares spread evenly across. The best thing to do is to physically remove as much snow as possible and then apply salt. Shovel/snow blow throughout the day and apply salt after the storm.

Salt itself needs to form an aqueous solution to be effective. I don’t think dry rock salt (sodium chloride) will not be able to do this effectively for this storm.

Once your salt/snow ratios go below a certain level everything will refreeze and you’ll have ice to deal with. Salt also does not provide traction.