Severe weather rampaged across the U.S. heartland, claiming at least 10 lives across Arkansas, Kansas and Oklahoma, in what has already become a historic spring storm season. Early Wednesday, the storm system was contributing to sleepless nights from Iowa to Texas, pelting many areas with golf ball-size hail. The powerful storms paid another visit to Joplin, Missouri, where a weekend tornado killed more than 120 people, making it the deadliest single U.S. twister since modern record-keeping began 61 years ago.