popcorn storm n. a brief, unexpected rain shower or thunderstorm. Also, collectively and more formally, popcorn convection. (source: Double-Tongued Dictionary)
Further reading
Get a shower or take a shower? Grace, a caller from Philadelphia, Pennsylvania, says her fiancé, also from Philadelphia, always says he’s going to get a shower, while she always says she’s going to take a shower. North American English usually...
Alan Connor serves as crossword puzzle editor for The Guardian, and his new book is a word lover’s delight. It’s called 188 Words for Rain: A Delightfully Damp Tour of the British Isles Led by Natural Forces (Amazon). The book opens 7,000 feet above...