A runner carries the Sochi 2014 Winter Olympic torch along a bridge across Yenisei River near the Krasnoyarsk hydro electric power station near the town of Divnogorsk outside Krasnoyarsk. Reuters

Unseasonably heavy snow has fallen near the mountain venues of the Sochi 2014 Winter Olympics and meteorologists are optimistic there will be no shortage of snow for the Games in February, Russia's chief weather forecaster said on Friday.

Weather is a virtually uncontrollable factor in the success of the Olympics in sprawling Sochi, where ice events will be held on the subtropical Black Sea shore and mountain events on the slopes around the Krasnaya Polyana district.

Unusually warm temperatures last winter prompted organizers of Russia's first post-Soviet Olympics and first Winter Games to store some 450,000 cubic meters (16 million cubic feet) of snow in the mountains just in case.

The surplus snow may not be needed. There is now a 52-cm (20-inch) layer of snow in Krasnaya Polyana, which is unusually high for this time of year, Russian Hydrometcentre chief Roman Vilfand told a news conference.

"There's normally no snow there in December, but it has snowed ahead of schedule," Vilfand said. "There is high probability that there will be snow above Krasnaya Polyana. The situation is favorable for now."

He said rain could be a threat to the snow layer, but did not elaborate on the probability.

Sochi Games chief Dmitry Chernyshenko has said previously that the weather was seen as a bigger potential problem for the organizers than security or infrastructure.

President Vladimir Putin has staked his personal political prestige on a successful Games in a location where most of the venues had to be built from scratch.

(Reporting By Polina Devitt, Writing by Alexei Anishchuk. Editing by Patrick Johnston)