It's Punky Brewster: Christmas in July (1985)
I'm following Wikipedia's convention and using the series's unofficial name to differentiate this from Punky Brewster. In the vein of Star Trek: the Animated Series, this is actually a sequel of the live-action series in which the main characters reprise their roles. Like many cartoons, each thirty-minute block was divided into two fifteen-minute chunks. We're only covering the half that relates to Christmas, obviously. The episode opens on a hot day in July. Punky Brewster and her friends stop to admire a skateboard in a toy store window. Punky muses over whether or not she's going to get it for Christmas, and she laments that she won't know for months. Fortunately, Glomer, the 104-year-old magical half-gopher/half-leprechaun in her backpack reveals that he's friends with Santa and might be able to help her find out. Maybe I should pause for a moment and give you a moment to review the opening credits to this show, which offer a tad more context: