Ok... Since you've banishes Sean98...
I've worked some winter weather in Wyoming and am recently back from Saskatoon. Coldest I dealt with was -31*F(reedom).
Layers. If you're gonna go sit at Olsen/BB then layers are your friend.
You'll be sedentary and exposed to whatever wind there is and potentially rain. The below is a layer or two short of -31* mess, but truthfully no one stays out in that very long
The below should have you sweating on Friday night and overkill on saturday & sunday
- Underroos -- briefs or boxer briefs
- Put on your socks
- Long johns over the socks and over the briefs
- Undershirt -- short sleeve
- Long sleeve shirt -- when I'm in the field it's a button down work shirt, for me usually cotton, but flannel is good too
- Jeans -- both shirts tucked in
- Sweater or sweatshirt
- On your neck... Neck gaiter. I like to put if on before the button up shirt so I can get it well tucked into the shirt, no gaps. Though I generally go with a full head /face covering balaclava. I can roll it off my head ears or put it fully on as needed
- Beanie hat
- Gloves. Mittens are better if you don't need to use your fingers
- Get a jacket or coat over everything
- Finally rain gear to stay dry
- Get a blanket or other padding between you and the bleacher
Edit to add... Hydrate like you would to work outside all day in August. Hydration is key to staying warm. And don't hold it. May God have mercy on you when you get the call from nature and it's time to dig through all of that.