I'm not aware whether this painting (The Sea Storm) I was looking at today in reproduction has been speculated about before as an influence on Turner. Jacobo Palma il Vecchio was believed to have been working on this commission when he died in 1528, so the task fell to Paris Bordone to complete it within the next few years. Venice's Accademia acquired it in 1829, while Turner's visits to the city were increasing in frequency. Turner painted the academic Dutch Boats in a Storm in 1801, the landscape Snow Storm: Hannibal Crossing the Alps in 1812 and some spare watercolors of sea storms before this. A year after the acquisition Turner produced
Rough Sea with Wreckage, then starting a decade later a flurry of storm oils, beginning with the seminal Slave Ship, which places the figures overboard in the lower right hand corner
Then all this within the next few years:
Sunrise with Sea Monsters, 1840-1845
(detail) Ever wonder where this guy came from? Just sayin'. A little shout out for Palma Vecchio. I go to bed now.