The Cascada is slightly longer than the Audi A5 and has room for four adults.
Three engines will be available at launch: a 1.4-litre petrol, a 2.0-litre diesel and a new 1.6-litre petrol.
The 1.4-litre petrol produces 138bhp and has a claimed average economy of 44.8mpg with CO2 emissions of 148g/km. The new 1.6-litre petrol engine produces 168bhp and does a claimed 39.2mpg with emissions of 168g/km.
At launch, the diesel option is a 163bhp 2.0-litre engine that's available with a manual or an automatic transmission. It does a claimed 54.3mpg and emits 138g/km. A 2.0-litre bi-turbo diesel will be offered later with average economy 54.3mpg and emissions of 138g/km. The bi-turbo unit will drive the Cascada from 0-60mph in 8.9 seconds and on to a top speed of 143mph.
The fabric roof opens in 17 seconds and can be operated at speeds of up to 30mph. With the roof stowed, the boot has a capacity of 280 litres. That grows to 350 litres once the roof is up.
The Cascada is available with Vauxhall's Flex Ride system, which changes the feel of the car to suit the driver's preference.
Two trims are available. Entry-level SE comes with 18-inch alloys, sport chassis and LED tail-lights. Elite trim get leather seats, heated front seats, heated steering wheel and front foglamps.
All Cascadas are covered by Vauxhall's lifetime, 100,000-mile warranty.
The Vauxhall Cascada will arrive in UK showrooms in April and will be priced from 23,995.