Extremely heavy rain fell in the NSW Snowy Mountains on the weekend, causing localised flooding in several areas, including along the Alpine Way and in Thredbo Village.

Between 4 pm Saturday and 6:30 pm Sunday, a total of 142.8 mm of rain was recorded at the Thredbo AWS (the automatic weather station near the top of Thredbo’s Kosciuszko Express Chairlift, which for the record, is Australia's highest weather station at 1957 m above sea level).

All that water cascaded down the mountain, turning small creeks into raging torrents and turning the Thredbo River – normally a crystal mountain stream a few metres wide – into a broad, muddy waterway which was 50 metres wide in places.

This dramatic photo shows a bridge across one of the creeks that feeds the Thredbo River at the height of Sunday's deluge.

Image: We're told the bridge survived intact. Source: Susie Diver.

And this one shows the river just across from the main bus stop in the village, an area that would be familiar to winter visitors.

Image: Sunday wasn't really picnic weather in Thredbo. Source: Susie Diver.

"It really was a flash flood event," Thredbo resident Susie Diver told Weatherzone.

"We're used to heavy rain in the mountains and we knew there was a lot of rain due this weekend, but with the intensity of this weekend's rain and with it falling on sodden ground, the water had nowhere to go."

Just below the mountains in Jindabyne, the lake is now listed at 100.15% capacity (a dam's capacity is its approved level for irrigation and drinking water supplies, but not necessarily the absolute amount it can handle before overflowing, which is why it can often exceed 100%).

Jindabyne locals are now boating and windsurfing on areas which are usually lakeside parkland, and all boat ramps have completely disappeared below the lake level.

Image: The main road into Thredbo Village was closed for a while on Sunday but its now open again. Source: Susie Diver.

The good news for sodden residents of the mountains is that a mostly fine week is ahead.

Meanwhile, as Thredbo straff clean up debris which has been deposited across the village's waterways, roads and paths, the weekend rain means that this could turn out to be wettest December on record at Thredbo AWS:

• The average December rainfall for Thredbo AWS is 112 mm.
• The wettest December on record before this year was 242.2 mm in 1999.
• Thredbo AWS has now had 231.2 mm this December to date, and while the week ahead looks dryish, early indications are that the period between Christmas and New Year has potential for more rain.

Image: The bridge to Valley Terminal and the main chairlifts was only just passable. Source: Susie Diver.