We only get shut down if the ice is bad enough you can't get up and down the hills. There are a lot of hills here. The ground drops quite quick from the mountains to the sound. Seattle and Tacoma are hilly enough that a manual car is torture in the summer.
Growing up on the east side of the mountains, we usually got freezing rain more often than snow. Two hour delays were the norm for new precipitation so they could chain up. They would try and drive a bus up the hill between Umatilla and McNary. If it couldn't get up, school was cancelled. Rarely was the ice bad enough that everything got shut down. Too much risk of cars sliding off the bridges into the Columbia or Umatilla Rivers.
In the 89-90 winter we dropped to -20 and 45mph winds for days. That was unusual cold for us. 0 was normal. Waiting for the bus sucked. School sucked because the main building was second hand structures bought off the army and at the most a room had a couple baseboard heaters. Water would freeze on the teachers desk. We did lessons with everyone on the floor against the heaters. The original school building had boilers and radiators so those classes were decently warm.
I'll take the cold over the heat though