The one thing about watermelons, aside from cutting them in the first place, is finding the space to store them, in all their roundness, in the fridge.
As a solution, especially with all the heat going on in the I.E., the following Watermelon Granita recipe sans the alcohol:
4 1/2 c. watermelon juice
1/2 c. sugar
1. Cut watermelon into pieces and blend to extract juice
2. Heat half of watermelon juice and sugar in a small pot over medium flame and stir to dissolve sugar.
3. Add lime juice and remaining watermelon juice
4. Pour into square baking dish, freeze
5. Scrape mixture with fork after an hour. Continue scraping each hour until entire mix is slushy.