It is going to get VERY cold during the next few days in Houston, and something we don't often have to think about here is, low humidity! Of course, outside may be plenty humid, but inside, when we turn on our heaters, the air dries out. The "healthy" range for violin family instruments is considered 40-60% humidity. If your instrument, which is normally used to 50% humidity, quickly drops to 30%, that can cause the wood of your instrument to contract quickly - this leads to slipping pegs, open seams, and in some cases, cracks.
So, it is important to help your instrument stay healthy by paying attention to the humidity level in the location where you keep your instrument. If you cannot keep your music room or house at a stable humidity level, ideally in the 40-60% range, then you will need to either buy a device, such as a Dampit or Stretto, use a humidifier in the room, or make a home made device, such as a damp sponge inside of a plastic bag with holes inside of your case (just be careful not to allow leaks inside of your case or instrument!!).
Cold weather doesn't need to be scary for instruments, you just need to plan ahead to prepare for your instruments sake! :) Take care and stay warm!!