1

You wake up ill. You catch a cold. If you keep your self in cold conditions 25% to become worse, with fever, etc. Try to be creative on this one... Healing the cold demands either 4 hours in a hot environment drinking tea, or casting spell lesser restoration or paladin's lay on hands or some clerics paid services. Level 1 Just nose and pain on throat, sneezing, Level 2 Fever, Level 3 Incapable of moving you need bed and medical care. Also 25% to give it on random companion close to you.

2

You get a mini frostbite on face, foot, hands. You need to take care of that or this becomes worse. Either healing with medicine DC 12, or lesser restoration or something helps you. On fail you keep track on level of frostbite. Level 1 is just annoying you, Level 2 gives you a disadvantage depending on the part of body you get it. Level 3 You lose an ear, finger, or something getting a 2d6 cold damage on the morning.

3

You couldn't sleep well. You have one level of exhaustion. You could rest 4 more hours to get rid of it.

4

You lose some of your equipment you had on your travel pack. It could be some gold, some small thing you carried. Roll a table for that or DM picks something for you

5

A weapon of yours gets damage from cold. Either the string of bow is cut, a dagger loses its hilt or something. You need to repair it.

6

You feel so cold today. You want to stay at a hot place for the rest of the day.  You are grumpy and you whine for everything during this day.  How the nine hells did you decide to sign up for that? You get one disadvantage this day. DM's call.

7

Nothing happens to you.

8

Nothing happens to you.

9

Nothing happens to you, but also to one of your companions of your choice.

10

Nothing happens to you, but also to one of your companions of your choice.

11

Nothing happens to you, but also to two of your companions of your choice.

12

You get great inspiration from your survival skills so far. You have an advantage roll on anything you want once this day.