In spite of the torrid conditions, Weening went out on his own, breaking away from the large challenging group to cross the line 2 minutes and 37 seconds in front of second-placed Maximiliano Ariel Richeze, the Argentinian who rides for Etixx–Quick-Step.

Poland’s Maciej Paterski of the CCC Sprandi outfit, who joined the top two in splitting from the pack, came through in third.

There were significant changes at the top of the leaderboard as Kelderman, who competes for LottoNL-Jumbo, finished in fifth place to surge to the summit of the standings.

Kelderman now has a 16 second advantage over Frenchman Warren Barguil of the Giant-Alpecin team, who could only manage seventh.

Cannondale’s American competitor Andrew Talansky occupies third spot on the standings, while Team Sky’s Geraint Thomas suffered a difficult day as he dropped down to eighth, 56 seconds off the pace.

“This is a WorldTour race, and it’s a pretty strong field,” said Weening.

“A lot of the riders are preparing for the Tour de France here,”

“It’s really important for me and the team.

“With this team I have a lot of freedom, I can do my own thing, and it works out well for me.”

Such was the appalling nature of the conditions on the mountainous journey, several riders pulled out of the race before the summit finish, opting to seek shelter in their team cars.

Lieuwe Westra and Lars Boom of the Astana team, Dimension Data’s Kanstantsin Siutsou and Tiago Machado of the Katusha outfit all withdrew before completing the stage.

The decisive move from Weening came at the 7.5km to go mark as he charged for the line, fending off the rest of the field to seal a brave victory in 4hr 33min 47sec.

The International Cycling Union (UCI) WorldTour event continues tomorrow with the longest stage of the race – a 224.3km route from Arbon to Sölden in Austria.