Packing for a trip during the colder months or to a wintry destination, is obviously different than packing for a beach vacation. If you're traveling with kids especially, all the warm gear you need can add up: boots, coats, snow pants... all of it bulky and probably heavy. I'm already thinking about this since we're headed to Sweden for the Christmas season this year, and I know that with lots of snow and temperatures that can get as low as -25 Celsius (or colder!), I have to pack a lot of bulky winter clothes.
One way to reduce the burden, is to pack clothing that can do double duty. Here are my favourite double-duty items:
1. A windbreaker that is also rain-proof
Some windbreakers are water-proof, others are not. I love the ones that are, because that means I can pack one jacket instead of two when we're headed somewhere potentially windy and rainy. Also, I love layering as a dressing-for-the-weather strategy, and a water-proof windbreaker is the perfect top layer in most kinds of weather.
Just like with the jackets, it really saves luggage space and aggravation if you can pack a pair of boots or shoes that can be used in the rain, but aren't "just" gum boots. All winter boots should be water proof, in my opinion, just because snow often turns slushy.
3. A sweater that can be worn alone or under a jacket
These are sweaters that are warm enough to wear on their own if the weather isn't too cold or windy, but that can also function as a liner under that water-proof windbreaker if the weather gets colder and wetter. Fleece works well, wool too, or any other favored sweater-material. The key is that the sweater isn't so bulky that it can't be worn under the jacket, or so thin that it doesn't do much by itself.
4. Thermal underwear
If you're headed somewhere with a serious chance of sub-zero temperatures, a set of thermal undies can be a really good thing to invest in. Using them can eliminate the need for bulkier cold-weather gear, by adding warmth under your regular clothes. For example, a long-sleeved shirt and long leggings that are thin enough to be worn under your regular clothes can make a day out in freezing weather much more enjoyable. The leggings are especially good of you're going to be very active, for example skiing, tobogganing, or snowboarding, since they can also be used under snow-pants to provide warmth without being bulky.
5. A towel that is also a bathrobe
This might not seem like a very necessary item for cold-weather destinations, but going to a pool is always a nice option when you're dealing with rainy, cold, or snowy weather on vacation. Bringing a bath-robe-y item that can also be used as a towel will save luggage space. Hooded towels work great, and so do highly absorbent bathrobes. When dry, these can also be used to snuggle in before bedtime or in the morning.