I don't think it matters if you are getting married in winter, spring, summer or fall...just the thought of standing up in front of that many people makes me break into a nervous sweat.
Now, maybe you are comfortable in those situations, but I sure as hell am not.
After surviving a few DC summers, I've learned a few things about deodorant. Namely, that it has to actually be an anti-perspirant.
And the best one?
Yup. It's ugly. It's not going to look cute and fun on your bathroom counter. But it works.
You have to remember to put it on every night before bed, and I would recommend starting at least a week before you need to be sweat free.
The other option?
I'm not kidding.
It's not exactly cheap, probably at least $500 a pop, and it's really only for hyperhidrosis but that REALLY works.
Personally, I'd try the drugstore option over the needles, I'm just putting it out there.
And stay cool and calm on the big day (even if it's the dead of winter!)