The last time we saw a BMW 4 Series prototype, it was in a decidedly different climate. Cold-weather testing in a convertible is arguably more critical than rolling in temperate conditions, because a top that doesn’t seal well is one that’s not fun to drive when temps are below freezing. And with the next 4 Series dishing up a traditional fabric roof, it’s critical to make sure occupants stay nice and warm inside.

There’s still plenty of camouflage to be found front and rear, but there’s a curious difference on this particular test car. Trapezoid exhaust outlets now exist at the back – the current 4 Series uses round tips and previous spy photos featured them as well. BMW’s larger 6 Series and 8 Series coupes run the trapezoid look, so it appears the new 4 Series could follow suit. That also means we could be looking at a production-spec car under all that camo.

Gallery: BMW 4 Series Convertible spy photos

The front is still well-covered, but we expect things to closely resemble the new 3 Series underneath. If anything, the grille could take cues from the Z4 to help set the 4 Series apart from the saloon. It rides on the same platform underneath though; that combined with a return to the folding soft top instead of a hard top should give the new convertible significant weight savings from the current model.

Interior and powertrain options should mirror what we see in the new 3 Series, with four and six-cylinder engines powering the rear wheels. A Plug-in hybrid version is expected as well, though that will likely come much further down the road.

Speaking of which, when will the 4 Series convertible be revealed? The new 3 Series isn’t even in dealer showrooms yet; that should happen next month. We haven’t heard a definitive date for a 4 Series reveal yet, but at this point, it looks like we won’t see the car until late this year or possibly 2020.

Source: CarPix