Between the use of easily obtained hand warmers and toe/foot warmers along with layers of warm wool/fleece/down/synthetic insulation type clothes (with something wind resistant with a hood as the final layer), combined with a garden style closed cell foam kneeling pad (hidden under your clothes to get it in) to put atop the bleachers to stop conductive heat loss and you're good for 4-5 hours of outdoor comfort...
Trapped air layers are your friend...
The wind is forecast to be from due west so those in the west stands will be shielded from the direct breeze... As long as the game is over by midnight I doubt that a low of 17 (even with windchill factored in) will be experienced...
The Worst case scenario appears to be right around 20 degrees... Which is plenty cold but easily endurable if you're dressed properly...
Wear semi-loose shoes/boots with two pair of socks (at least on thick pair)...Avoid cotton material at all costs if possible... (when cotton gets damp it will stay damp and can cause you all kinds of issues in seriously cold weather)...
Drink some hot chocolate during the first and third quarters and you should stay toasty while you cheer for the Cream & Crimson, and..., for goodness sakes..., if you've gone thru all the trouble to bundle up properly and get there..., stick things out to the very end and be there to celebrate the return of The Bucket and help make the Team aware of how special this particular W really is... If you don't see The Bucket held up to the stands by our Team then you really haven't experienced a Bucket Game...
A decent fleece or wool balaclava that covers your ears along a fleece or wool scarf plus old fashioned style mittens will go a very long way towards ensuring your comfort and should be considered necessities...
Have fun. I envy you...
Here's a decent synopsis of what I was trying to convey above from a more authoritative source (actually I'm an Expert in this area (years of Alpine mountaineering, winter camping,and skiing experience) but there's no way you can verify that so I give you this...):
Someone mentioned in another thread to not wear all your layers while walking to your seats to avoid sweating which is absolutely correct... Any serious sweating can cause a myriad of cascading negative issues that all lead to from very cold to even freezing outcomes...