Shooting outside in snow and cold...help

I usually do not spend a lot of time in the cold (have seen -57degrees where I live) but I have been asked to shoot the ceremonial startup of a dog race next month. I shoot with the 50d with a 580 EXii flash and am looking for any advice on what settings I should use and or things to remember...my subjects will be a musher and a lottery winner in a sled being pulled by dogs. of course the dogs will not be moving when I take the picture.

Is the photo in the daylight or at night/evening? If daylight: how bright is Alaska daylight in February?

It is 11 am and it will be foggy/frosty...due to the cold air.

Maybe a little exposure compensation to keep the whites really white and not grey. If it's really bright I think ND filters are supposed to help, but I have limited experience with shooting in snow. We don't get that much here in TN. That's about all I can think of.

Your batteries are going to take a massive hit from the cold. The best solution is to take plenty of spare batteries, for both the camera and flash, and keep them warm in an inside pocket. Adding a hand warmer will help immensely. Be sure to change out the batteries often during the shoot.

Thanks Josh...I plan on going out each day at 11 am the week prior to the event to get an idea of what I will be up against as the weather will have a lot of control. I plan on wearing a heated vest syo the batteries will stay warm. I think my 28-80 lens should do the trick...or am I way off on that?

Do you shoot RAW or jpg? For snow with sun/shade/etc I would suggest RAW and pack a grey card to get the WB correct later.

+1 on the batteries in the cold.

Do you have gels for your flash? Might need some blue to match ambient then correct later.

I'd use one of your primes instead if the subject isn't going to be moving.

Only shoot raw. Thanks for note on prime.... haven't used gels on flash...but can... My big concern as well is the batteries...but I do have quite a few for both the camera and flash. And I plan on spending a "setup" day shooting the expected number of shots x 5 in the same conditions expected the day of the shoot so I will have some idea of what to expect from the batteries. I will post some of those shots for further advice....thanks guys. This a new event for the organization I am shooting for so I want to make sure it works out for all involved.