Didn't say car. I'm just saying cold. Say it was stored on property but outside.
If it crashes, will it be obvious by looking at it? And can it be "saved" after that?
Chrystals will settle to the bottom. Thats the steroid.
Gradualy warming the vial with stopper above water in a small cup of warm/ hot water can redisolve it.
Bringing it inside from very cold can cause it to crash. If I do, I slowly warm it. Like in a cool area first then, warmer...My Garage gym gets cold in winter up here. Ive seen that happen. Its likely condensation inside the vial introducing some moisture.. The sudden temp change does it worst.
Try to store at stable temp is best.