The above pictures were taken outside our house the morning of January 28, 2004. The temperature over night went to -45C with strong winds bringing the wind chill temperature to -55C. At this temperature exposed skin will freeze in less than 30 seconds. An exposed Chameleon would be dead in just seconds.
Of course nobody would let a Chameleon go outside in temperatures like this however there are a number of considerations for cold weather survival for your Chameleon. One is emergency heat. In 1998 there was a huge ice storm in the Canadian Province of Quebec. Ice built up on power lines and caused the lines to snap. Hundreds of miles of lines were down and 1.4 million people were without power - some for a week or more! I know of at least one breeder who lost every single Chameleon in that storm. A month ago, I sent two Chameleons to a new owner in Quebec and sadly a prolonged power outage last week killed them both.
No amount of planning could protect your Chams from a 3 week power outage but if you live in an extremely cold environment there are a few things you can do. Make sure you have a few sources of heat. This will keep you AND your chameleon safe. You should have electric space heaters, a gas and/or wood fireplace and consider a backup electrical generator. Never use a bar-b-que or other propane heater inside without proper ventilation and professional installation - many people have died from this method of keeping warm.
Pick a small room that you can heat using one or more of your auxiliary heating methods and close off the rest of the house. Keep a supply of blankets and warm clothing handy. Have a small emergency cage ready that can be used to house your Chameleon for short durations and be ready to move the emergency cage into your heated area. It may seem weird to have you and your Chams all bundled up in the living room in front of the fireplace but it could easily save lives.
In the winter your Cham will have no opportunity to bask outside. Less light means less vitamin D and poor Calcium processing. You will need to be sure you are using new UVB 5.0 bulbs and providing lots of calcium and occasional supplementation with a good multivitamin that contains D3. Remember that even an expensive Reptisun 5.0 will slowly drop UVB output until it is useless at about 6 months of age. Sure it's still putting out visible light for years - but no UVB! Replace your bulbs twice a year.
A trip to the vet may be necessary in winter months. A few heat packs and a sturdy cardboard box can be helpful. Put your Chameleon in a plastic container with a branch to cling to. Place the container inside a cardboard box packed with news papers and add two 10 hour heat packs. Seal the box against drafts. Make sure to warm up the car before you take your Cham outside and keep the trip as short as possible.
It's nearly impossible to find a variety of insects in the winter. Even getting live crickets can be hard. Yet without a variety in prey your Chameleon may start a hunger strike. This is a natural instinct to prevent your Chameleon from eating too much of one type of insect and possibly missing out on nutrients it needs.
Make sure to get a good supply of Superworms and use them sparingly as a treat. I have heard some people have used colored powders to make crickets look different. Spirella is a green powdered herbal supplement that is healthy for your Cham and can spice up a plain dull cricket. You can also try crushed bee pollen to give your cricket an interesting yellow tinge. You can also order silk worm eggs and raise up a batch of tasty silk worms as a special treat.
If you have female Chams, you need to be prepared to get your laying bucket ready on short notice. When Sam was ready to lay her bucket was a frozen block of ice in the back yard and it took some scrambling to put together proper accommodations. Make sure you have a supply of tropical potting soil in the basement.
Don't think it couldn't happen to you - freak storms, power loss and severe cold temperatures can affect anyone in Canada, Europe and much of the USA. Preparation is the key to keeping your Chameleons safe and warm for the winter.