Severe storms have made their way through the southern US, leaving two people dead.

The worst of the weather has eased but the area of low pressure responsible for the storms is now threatening dangerous conditions along the Gulf coast into Florida before running up the Atlantic coast as a nor'easter by midweek.

The violent thunderstorms began on Saturday night, bringing large hail and damaging winds to parts of Texas, Arkansas and Mississippi.

The storms brought hail, slightly bigger than a baseball at up to 9cm in diameter, and downbursts on the accompanying straight-line winds that measured 140 to 150kmh. There was some structural damage and a number of trees were uprooted.

Local media said there was also a report of a possible tornado in Bentonia, Mississippi. Several barns and sheds were destroyed and at least six homes were damaged.

Jackson, Mississippi had 59mm of rain on Sunday, 40mm of which fell in just 6 hours.

This clutch of thunderheads is now moving across the Deep South. It is then forecast to slide up the eastern Seaboard turning increasingly to snow as it moves over the Carolinas into the Mid-Atlantic States.

This increasingly vigorous low-pressure system is expected to develop into the third nor'easter in 10 days. As such it will bring yet more heavy snow across the northeast.

Snowfall amounts will generally be around 10 to 20cm. However, Boston could get as much as 40cm of snow on Monday night into Tuesday.