During a cold snap, the slopes are littered with signs propped up on old rental-shop skis that read Caution! Snowmaking in Progress, skiing down in the path of a ground gun is like having millions of tiny needles driven into your face.  It’s best to keep your eyes closed, if you can.  Fat orange hoses run from the base to the gun, but can be skied over in deeper powder.  Before grooming, the ground guns build huge, concentrated mounds of false snow, creating miniature headwalls.  In a helmet and goggles, the snow crystals hit the hard plastic, causing an alarming ping! sound like driving through a cloud of insects.  It’s possible to avoid the guns by using a kind of primitive Doppler, steering away from the amplified hiss that drowns out the other hill-sounds.