Clementine will be around and perhaps playing in the snow a bit initially before shit really goes down and the weather gets worse. Because even if she has been through hell she is still an eleven year old kid. And prob bundled up in some adorable outfit Clara picked out. That is not her ski lodge jacket hahahaha.

With the attack she will probably rush to help at the clinic as best she can. And help try scout around a bit and get any injured there safely. Along with being bit at some point because why not have her almost freaking out at being bit then fever oh shit moment. And possibly. Actually show people how violent this kid can get as a result of surviving the walker apocalypse for two years.

Elsa on the other hand will probably be more at home because ice queen. Ahem. Though really, she wouldn't so much mind the cold as others. And will probably be outside watching and helping the children with their snowmen and the like. Because Anna and Olaf would demand it. Probably be a bit almost nostalgic and bitter over it because her own ice powers are gone.

With the attack, I imagine that Elsa would likely try to stay out of it, simply helping herd those not fighting somewhere safer if possible. Using her charm to distract the giants in the process.