Model could be introduced sometime later this year.

The 2017 Audi S5 Cabriolet has been spied undergoing testing on the Nürburgring.

Set to be sold alongside the S5 Coupe and S5 Sportback, the S5 Cabrio has an evolutionary design that borrows a number of styling cues from the new A4.  The camouflage does a pretty good job of hiding the details but we can see the model will have a prominent grille, sporty air intakes, and a four-tailpipe sports exhaust system.  Other highlights include a rakish windscreen, a power retractable soft top, and a decent-sized trunk with an integrated spoiler.

Power will be provided by a 3.0-liter TFSI V6 engine that produces 354 horsepower and 369 pound-feet of torque. It will be connected to an eight-speed tiptronic transmission and a rear-biased quattro all-wheel drive system. This should enable the convertible to accelerate from 0-62 miles per hour in approximately 4.8 seconds before hitting a limited top speed of 155 mph.

Buyers looking for something more powerful might want to hold out for the high-performance RS5 Cabrio.   It will reportedly eschew the current 4.2-liter V8 engine for a new biturbo 3.6-liter V6 that develops nearly 500 hp.

Gallery: Audi S5 Cabrio spy photos