Further storms across the Midwest USA by Tomasz Schafernaker
Severe thunderstorms tore through parts of the US Midwest on Friday, killing two people and cutting power to thousands of homes.
The storms developed along a Squall Line - a line of severe thunderstorms that form along or ahead of a cold front. Cold, dry air moved down from the Rocky Mountains and collided with warm and humid air further south and east. As the air masses collide, violent thunderstorms quickly develop. Yesterday, storms developed over the central and northern plains, the upper Midwest and the Ohio Valley.
In Iowa, severe thunderstorm warnings and flash flood watches were issued across the state on Friday. Strong squally winds accompanied the storms with gusts reaching 70mph (113km/h) in some areas. Hailstones the size of tennis ball fell near Earlham, 30 miles southwest of Des Moines. Two teenagers lost their lives when a tree was uprooted by wind and fell on their car during Friday evening.
Much of the Midwest has suffered from weeks of severe weather with torrential rain flooding vast areas of the Mississippi River basin. The recent storms have sent yet more water into the flood-ravaged Midwest, pushing the river levels up again.
The thunderstorms across the Midwest are expected to spread eastwards through the course of the weekend. Cooler and fresher air will move in behind with sunshine likely for much of the Midwest as high pressure builds.
