is this normal, or common?

[WeeNicole]

My humidity keeps dropping to 54-55% overnight! And climbs to 58 during the day usually mid day at its highest. Then slowly goes down in the evening and night.

What is this. My hatch is due tomorrow and this is not good.

I doubt I could put anymore water sponges in or ill flood it.

 

[WeeNicole]

Ok I found a draft that was hitting back of bator. Covered it with a tea towel and now humidity up to 57.

I hope iv not "hurt" the eggs with my negligence. Day 20 and no signs of hatching yet. Maybe they'll be late due to the draft. They were alive and well at last candling. Fingers crossed. Annoyed at myself