Is that really the geyser or an avalanche? From the way I see it, it looks more like an avalanche, note that Kogasa's speech bubble is coming from under that thing.
Snow-PlayFresh snow! ♡I'll go too!Look! Look! It's like a person!What are you doing?Kyaaah! Kogasaaaa!?Bwaa-!?I didn't know what other noise would make sense.Hah!!Poof