THIS is the stunning moment a US Air Force jet soars through the sky over Snowdonia.

Vapour bounced off the wings of the F-35 Lightning II as it sped over the Welsh mountains at a swift 575mph.

US Air Force Lockheed Martin F-35 Lightning II causes vapour to bounce off its wingsCredit: Thomas Winstone/News Images

The Lockheed Martin jet was taking part in a low-level training exercise through the Mach Loop – a series of valleys in North Wales.

Aviation and wildlife photographer Thomas Winstone spotted the high-speed aircraft on February 10.

Capable of Mach 1.6 – or 1,230mph – the F-35 is one of the most powerful fighter jets ever built.

Its manufacturers also describe it as “the most lethal, survivable and connected fighter jet” on the planet.

And it is cited as “critical to maintaining air dominance now and for decades to come”.

“With stealth designed in from day one, the F-35 has an unmatched ability to evade enemy detection and enter contested airspace,” Lockheed Martin adds.

A defence source confirmed the US is conducting joint exercises with the RAF.

F-35 LIGHTNING II

Maximum speed – Mach 1.6 at altitude

Range – 1,500 nmi (1,700 mi, 2,800 km)

Combat range – 669 nmi (770 mi, 1,239 km) on internal fuel

Empty weight – 29,000lb (13,290kg)

Fuel capacity – 18,250lb (8,278kg)