It is sarcasm, and has nothing to do with snorkeling. The phrase simply means that the weather is horrible. Therefore snorkeling would infact be impossible, unless you wanted to freeze yourself to death.
by SilentLemon January 8, 2009
She is the most awesome person ever in the Mysterious Benedict Society Series. She carries around a bucket full of everything she needs and is very agile and athletic. See also, Kate Weatherall.
by Juliana Renfroe June 8, 2013