Tasmania Police say they are "gobsmacked" a group of more than a dozen bushwalkers, including three children, had to be rescued from treacherous conditions on the summit of kunanyi/Mt Wellington.

The temperature dropped to a low of -3 degrees Celsius on the mountain on Monday night, with a feels-like temperature in the wind of -21.6C, and heavy snowfall, according to the Bureau of Meteorology.

Police said a group of 13 people on a day walk up the mountain phoned for help at 4:15pm on Monday after the weather closed in.

The group had mobile phones but "minimal food and water, and no equipment to spend the night in case of emergency", police said.

Police liaised with City of Hobart authorities, who drove through the snow up the mountain in four-wheel drives behind a tractor with a snowplough.

Another group 'in a very bad way' found while rescuers try to reach summit

Hobart Mayor Anna Reynolds said the group of 13 had coats and were sheltering in the observation deck at the mountain's summit, at an elevation of 1,271 metres.

While council workers were travelling up the mountain, they stumbled upon a group of five more walkers trying to descend at the 1,110m level.

Cr Reynolds said that group had to be rescued first whilst the larger group waited in the sheltered observation building.

"It was very lucky for them that our staff were going past and they were on the road," she said.

She said three of them "were in a very bad way" and the group of five was brought down to the Springs and warmed up.

Police said everyone was safely down from the mountain by 10:30pm.

'Quite frankly I'm gobsmacked'

Tasmania Police Inspector Kathy Bennet told ABC Radio Hobart that the bushwalkers were putting lives at risk.

"That potentially put other lives at risk because we had our search and rescue people up at New Norfolk, with the anticipated issues we had up there [for flooding response] … and we would have to think about redeploying resources to get people.

"If the road's closed don't walk up there, it's as simple as that.

"Snow and low clouds are not good walking conditions especially when you have three children involved on the walk, which is what there was."

Premier lambastes walkers' 'stupidity'

Premier Jeremy Rockliff called the situation "simply ridiculous".

"Thankfully, local government supported that rescue when our SES personnel and others were out supporting other communities."

Police Inspector Darren Latham said it was incredibly frustrating that police had to constantly warn walkers on the mountain — especially during a severe weather event.

"The Bureau of Meteorology, the SES and Tasmania Police have been issuing warnings to the community regarding the severe weather event since last week. This included several bushwalker weather alerts," he said.

"Bushwalkers should always prepare for the worst. Our emergency service personnel often put their own lives at risk during rescues, so it is frustrating when the situation could have been avoided."

Pinnacle Road, the access road up the mountain, is closed at The Springs on Tuesday. You can check the latest road status on the City of Hobart website.

For a forecast of the weather conditions on kunanyi/Mt Wellington, visit the BOM's website.