Cirrus grew up near the weather factory. Like most of the Snowflake family, she enjoyed snow and went on family trips to the ground during winter, where she and her cousins would play in the snow. Her family was relatively well-off, and they owned a decent-sized cloudhome.
When she was little, Cirrus' father would take her to the weather factory, where he and his brothers worked. She enjoyed making snow, but she only did it for fun, and her snowflakes were rarely used unless there was a shortage. One winter night, just before Hearth's Warming Eve, there was a rush at the factory: a blizzard had been scheduled for Trottingham, but several workers were unavailable. All the workers who were there had to work double -- even Cirrus, who was visiting and still relatively new at making snow. Everypony worked as hard as they could, and even though it was a rather stressful night, they managed to produce just enough snow for the Trottingham blizzard. Cirrus, a fidgety filly, impressed everypony who knew her well by working the entire night without complaining or taking a break -- quite a feat for a pony who hated hard work. When they were done, she fell asleep from exhaustion, and awoke to discover the snowflake on her flank.
After earning her cutie mark, Cirrus started working full-time at the weather factory. Though winter was by far the busiest season, she discovered that the factory's Snow Division operates all year long so it could snow on the mountains, as well as in the cooler parts of Equestria. Her job at the weather factory is twofold: producing snow and teaching inexperienced snowmakers.
Sleety Snowflake is Cirrus' father. When Cirrus was a filly, she spent most of her time with him. He was the one who introduced her to her current job at the weather factory.
Selene Snowflake is Cirrus' mother. She operates an art gallery of ice sculptures.
Slushy Snowflake is Cirrus' younger brother. He was born shortly after Cirrus earned her cutie mark.
Cirrus is a highly energetic pony. She talks a lot and speaks very quickly. She loves her job at the weather factory, and considers it more fun than work. (Unless she's on call, of course!) She doesn't have very many friends, but that's mostly because she doesn't spend much time in any one place. When she was a filly, she didn't hang around with ponies her age, preferring the weather factory where there was snow. This trait stayed with her for several years, but she enjoys talking to anypony, though she mostly talks with other pegasi. Cirrus frequents the Ponyville café, and eats dinner there most nights. She's always hungry!
Her favorite season is winter. Even though she has a lot more work to do, she doesn't mind, because she loves the snow. On weekends, she likes taking an extra snowcloud home from work to keep in her home, as she enjoys chilly temparatures.
"I hate Winter Wrap-Up." -- Cirrus, every Winter Wrap-Up.
Cirrus doesn't have very many unusual skills -- her biggest talent is making snow. She's a competent flier, but not very good at flying quickly -- it makes her nauseous. However, she is very agile and graceful in the air, and likes doing tricks. They might not be impressive, but she thinks they're fun.