When the power goes out, it’s important to plan to be indoors in order to keep as warm as possible. You should also:
Keep a torch and spare batteries handy (it's important to not use candles!)
Charge your phone, laptop or any other electricals you may have
Keep your fridge/freezer door closed
Get a thermal flask so you can have access to hot water
Make sure you're aware of your phone provider's data allowances if you need a boost while wifi is down
Keep a warm jumper, blanket or scarf, gloves & hat handy to stay warm
Keep some food available that can be eaten cold
Get a cool box for any medication that needs to be kept cold