Severe storms battered the US’ Midwest on the evening of December 15, hours after President Joe Biden pledged increased federal assistance to the state of Kentucky, where scores were killed and towns levelled by recent tornadoes.

The National Weather Service (NWS) warned of an “extremely strong” and “potentially record-breaking” storm system producing “a plethora of weather hazards” throughout several states in the central and northern part of the country on the night of December 15, including “dangerously high winds”, snow, thunderstorms, tornadoes and fire risks.

“These storms will have the potential to produce extreme wind gusts as high as 100mph (161km/h), as well as a strong tornado or two” in Iowa and Minnesota states, the agency forecasted, with local NWS office Twitter accounts urging people to take shelter due to confirmations of rare December tornadoes.

More than 400,000 customers were without power in several US states in the evening of December 15, including Colorado, Kansas, Missouri and Iowa states, according to poweroutage.us.

The latest extreme weather comes only days after violent tornadoes ripped through several southern states, including Kentucky state, where US President Joe Biden visited earlier on December 15.

“The scope and scale of this destruction is almost beyond belief,” the 79-year-old president said after visiting the towns of Mayfield and Dawson Springs.

“These tornadoes devoured almost everything in their path,” he said in Dawson Springs in western Kentucky.”Your homes, your businesses, your houses of worship, your dreams, your lives.”

Biden said the federal government would foot 100 per cent of the bill for emergency relief for the next 30 days and will continue to do “whatever it takes, for as long as it takes”.

Biden, who has made empathy one of his trademarks, strolled down a ruined street in Mayfield, stopping to chat and shake the hand of a woman who was seated in the rubble of a collapsed building.

Wearing a baseball cap and a dark blue suit with no tie, the president paused in the street at one point and bowed his head in prayer with the town’s mayor and several other people.

Before touring Mayfield, a town of some 10,000 people, and Dawson Springs, population 2,500, Biden received a briefing on the damage from last week’s tornadoes, which killed at least 74 people in Kentucky state and 14 in surrounding states.

“There’s no red tornadoes, there’s no blue tornadoes,” the president said in a reference to the colours of the nation’s two largest political parties – the red of Republicans and the blue of Democrats.

In addition to federal aid, more than 500 National Guard troops have been deployed to help with law enforcement, traffic control and recovery, along with volunteers and associations on the ground to support victims.