Extreme weather is like debt, obesity, and prescriptions for anti-depressants: Every year, there's more of it. 2011 was no exception, and scientists have just added another distinction to its record-breaking trophy case of awfulness: Nearly 200 tornadoes in a single day. The three-day storm that birthed that record killed 346 people.
Whether or not this one event is directly attributable to climate change, which is always a challenge to establish, scientists at NASA say that climate change could lead to even more tornadoes. In other words, given the path we're on, the records of 2011 aren't likely to stand long.
Tornadoes in 2011 Set Deadly Records, Scientific American.