KANSAS CITY, Mo. (AP) - Even expert storm chases would have struggled to decipher the difference between the tornado warnings sent last May before severe weather hit Joplin and, a few days later, headed again toward downtown Kansas City.

The first tornado was a massive EF-5 twister that killed 161 people as it wiped out a huge chunk of the southwest Missouri community. The second storm caused only minor damage when two weak tornadoes struck in the Kansas City suburbs.