Our daughter is home from school and hers ('12 Civic) sat outside through the worst of the cold. I asked my wife if she thought it would start or not as I was walking out to it to check (vs our daughter trying later when I'm at work and it doesn't start). Fired right up and quickly. No slow crank at first, which is not unusual when cold, either. Probably helps that I trickle-charged it for a day just a month earlier when she was home for Thanksgiving.The only vehicle that sits outside is my 2012 Honda Civic.
I have found jump packs to be worthless unless you spend a lot of money (like several hundred) in which case you might as well buy a battery. I have picked a few up over the years on sale for $50-100 and they have all been junk and deliver no where near their advertised cranking amps. I have used the smaller lithium jumps packs on ATV's with great results. They are small and can fit in a a small tool bag for rides.Mine sat for 3 days in my uninsulated garage and fired up no problem.
My good friend lost one on Friday when he left work, he went for his jumper pack in his trunk and found out it was a goner and could not be revived. So he got a jump, and went straight to AAP and got a battery. He has not replaced the jump pack yet.