Boiling water turning into snow

[Baby Astronaut]

 

Why doesn't her breath show in weather cold enough to instantly turn airborne boiling water into snowy dust?

[Baby Astronaut]

Anyone?

[swansont]

Too faint/diffuse to see? There are times I can only see condensation when I blow air out, i.e. with a more restricted exit from my mouth, but no so much with normal exhaling or talking.

[Janus]

I'm going to say low relative humidity of the air. In essence, the air takes in the moisture in the breath without it condensing out. However, when she throws the water into the air, There is too much moisture for the air to hold and excess condenses out and freezes.