The name of the new car remains top secret, but Autocar understands it will be announced at a press conference at the New York motor show at around 17.30 UK time tonight.
The New York announcement will also confirm that the new sports car will initially be sold as an open-top two-seater, rather than in the coupé form of the C-X16 concept. It should go on sale in mid-2013.
The decision to launch a roadster first is believed to be because Jaguar is keen to get the car to market as soon as possible. A coupé is expected to follow around a year later.
The powertrain for the launch vehicle is expected be a 375bhp, 332lb ft supercharged 3.0-litre V6 mated to an eight-speed ZF automatic gearbox. The V6 is new and has been developed from the latest V8, partly to give the company an entry-level, tax-busting engine in China.