The Gulf oil spill was no exception, and many unexpected developments—from the Gulf economy taking a huge hit to oil getting trapped in the cold depths—foiled many an expert prediction.

A year later, here's a look at some of the major surprises from the spill.

(Read more stories about the Gulf oil spill anniversary.)

When nearly five million barrels of oil gushed into the Gulf of Mexico (map) last year, experts warned that some of that crude could be headed around the tip of Florida and straight up the East Coast, courtesy of the strong Gulf Loop Current