Not sure if this is the right place but how cold is too cold for practice? I am faced with this decision tonight as our first practice is scheduled for 6:45 - 8:15 pm.
I honestly think if it's above freezing it should be fine. Bundle her up. A beanie, a hoodie with pockets she can warm her throwing hand in. Extra layer under pants.
My daughter has practiced and played many times I. This weather for 10U softball. The truck is to have as little down time as possible and keep them moving or doing calisthenics.
Our team usually practices outdoors as long as its above about 45 or so and not windy. We've played games in the 30s but as far as I'm concerned that's about the limit. Anything colder than about 35 is just miserable for baseball/softball.
My daughter is 10u and we are in OKC if that makes a difference.