To emphasize what some others have said, a $40 pair of heavy tire chains
and a sturdy shovel can get you back out of situations like this.

In California you are required to carry tire chains when the chain controls are on (on the interstates most every time it snows)
If you have a 4 or
all wheel drive and good snow tires, you usually are not required to put them on,
but you will still get a ticket if stopped and you are not carrying some.