"She was dressed in…a woolly sweater, long black tights with thick blue socks, and hiking boots…[Her] sweater was blue, white, and gray with a snowflake-patterned yoke. It was enormous, stretching almost to her knees.”
This looks like something Mary Anne would wear, but apparently even ghostwriters can take a break from jumpsuits, neon and high tops (I think they may have even put Jessi in something other than a leotard once).
Alas, I haven't included a shopping guide to this particular outfit since I couldn't find a satisfactory snowflake-yoked-chunky-fairisle-sweater at my usual online haunts. Luckily, I'm sure any number of artists over at Etsy would be happy to recreate similar socks and sweater if you asked nicely.