‘Potentially historic’ flooding threat looms after almost 100 tornadoes hit US

Rainfall near Memphis, Tennessee, is expected to exceed 12in over the next three days

A prolific tornado outbreak will give way to a rare and widespread flooding threat across the midwest and southern US this week, stressing the nation's short-staffed weather forecasting and disaster response efforts.

At least seven people have reportedly died so far as nearly 100 tornadoes struck on Wednesday.