[ahofmann]

Moving water will get much colder than 0℃ before turning solid. -10℃ or even -25℃ are easily possible. If the water is also under pressure, it can get even colder.

[fsckboy]

I thought to supercool water, it needed to be completely still? am i confusing it with superheating?

[ahofmann]

I don't know much about water. I just remembered that rivers aren't freezing at all, even in harsh winters and searched a bit on the internet.

To be honest, I'm writing this comment mainly to say: what a great user handle, I smiled :-)