During cold, winter months, avoid exposing an instrument to rapid temperature changes. To avoid
permanent damage after transporting an instrument through outside cold temperatures, leave the instrument in the case for awhile, so it can gradually adjust to room temperature.
If the instrument has been outside in a locked car for a few hours, it may take two hours or more to adjust.
A cold acoustic instrument will develop finish cracks when the finish doesn't warm up as fast as the wood.