I have determined this based on years of previous experience. I had my snow tires taken off today. That greatly increases the likelihood of snow. And frankly, it has been cold enough.
It is nice to not have to listen to the click-clack of the studs on bare road though.
I have a 2010 Prius. It has a key, but you just press the "power" button to start it up. There is no place to actually put the key in the car--in your pocket or purse is fine as long as it is within a certain range.
When I got to the garage first thing this morning, I could not find the key. I searched my purse, my pockets, and then all over the car. Since I drove it there, I knew it had to be somewhere nearby. I said I was sure it was somewhere in the vehicle so it could be started. I left for a walk but the mechanic came running after me. He couldn't start it--I must have the key somewhere on my person. I had patted my coat pocket several times and had not felt the key, but when I actually put my hand in the pocket, I found it. Sometimes I can be very ditsy. Usually early mornings if I have to actually do something like get the car to the garage first thing.
I was reminded of a substitute job I had after I retired from full time teaching. I had a class that was made up of some kids on the autism spectrum. I don't even remember what prompted the remark but I said something about having a "blonde moment." I looked out at several very dubious faces. "Okay, I guess you are all wondering how I can have a blonde moment when my hair is grey."
I had failed to impress them with my self-deprecating humor, but they were quite astounded by my mind reading abilities.