Headquartered in Wisconsin, the USCCA staff gets the chance to appreciate all four seasons. Appreciate may be a strong word when it comes to ice storms in January.
Knowing we may experience inclement weather, we all usually have a winterized bug-out bag including a few extra protein bars, warming packets (Hot Hands Warming packets are great for winter activities), and a couple of thermal rescue blankets.
I always have a thermal blanket in my bag, you never know where someone might need rescuing - and that includes a fall into water or something else you may need to get them warm - or keep them from going into shock.
An extra changes of clothes and spare socks and shoes. Louisville usually has a relatively mild winter compared to our northern brethren.
I leave my hunting overalls in the back seat of my truck. They are insulated, water resistant, and have my hunting gloves stuck in the pockets. If they can keep me warm enough to walk through winter deer season conditions, they can keep me warm enough to wait for help, or walk to get help in bad weather.
My bag doesn’t change.
My trunk changes. An extra blanket, an ice scraper, some salt, a candle, etc.
Similar idea in my house, with candles, heating fuel, etc.
But my bag doesn’t change. I’m either holing up in my house or driving somewhere else. I don’t need snow shoes to bug out.
Mini steel garden shovel or military folding shovel (So it can be used-for ice) found the garden shovel is a little more stout and the same size
Military German sleeping bag (Bottom folds up and has arms So it can be used as a jacket)
12 hour emergency candle with holder
Gortex gloves and wool cap, neck gator
Cat litter
Normally I’d say, what’s snow and winter, but tomorrow we are actually forecast to get 1" of snow, crazy!!!
It’s been many years!
But in winter I make sure there is always a sweatshirt in the truck along with a beanie and fluffy gloves.
Those hand warmer packets are great as well when the temps get below 45 or 50.
Hey, just because I live in SoCal doesn’t mean I can’t enjoy 4 seasons too!!!
There’s Spring (Hot), Summer (hot as Heck), Fall (ALSO Hot as Heck), Winter (Damn 65 degrees…it’s freeeeeezing!!!). It may not be the same as your seasons…but let me tell you…65 degrees can be cold when all you own is shorts and t shirts.
I read that as Spring (Too Hot!), Summer (OMG we’re all going to die!), Autumn (Too Hot!), and Winter (little on the warm side). 
I add a good sleeping bag to the truck. I have my hunting jacket (browning quattro parka), gloves, hat and boots.