Riding on the track during the raining season is a much different thing compared to riding on the street, usually because most classes permit wet-weather tires and the tracks won't be tarnished with oil or any other muck.
Unlike riding on the street in the wet, some guys love the rain, and it's often the great equalizer for those who wouldn't usually have the equipment to display their talent in the dry.
Wet-weather tires are super soft and incredibly grippy, enabling you to push to a whole new level in the rain compared to what you could on regular DOT tires or slicks. In saying that, you still need to build confidence and work your way up to the pace you feel comfortable with because the possibility of crashing is still much higher than it is in the dry season.
They say practice makes perfect, both in your performance and in your motorcycle's settings, so next time it's wet and your friends are in the pits, get out and put in the laps. You'll be laughing come raceday in the wet.