Very interesting paper indeed! Really BIG equatorial storms on Titan are discussed in another recent (online) paper in Nature geoscience (Nature Geoscience 8, 362–366 (2015) doi:10.1038/ngeo2406).
http://www.space.com/29090-titan-methane-s...sand-dunes.html. , concluding such storms may be responsible for sculpting the apparent west to east migration of Titan’s equatorial dunes. As I understand it the storms height reach altitudes where stronger west to east winds exist producing a downdraft gust front at the surface going west to east up to 10 times the velocity of Titan’s usual east to west surface winds.
I may have missed it but I would have liked to seen the authors of these papers model other features of the really big storms like the “arrow storm” in 2010 (with its 1,200 kilometers in length east-to-west and wings that trailed off to the northwest and southwest each 1,500 kilometers long) or the April 2008 storm described in the Schaller et al paper
http://www.nature.com/nature/journal/v460/...ature08193.html both of which created clouds far removed from their propagating centers (?due to Rossby wave effects?)