It's lazy to blame global warming for extreme weather events. Madhav L. Khandekar reported in "The Global Warming-Extreme Weather Link" that extreme weather events are part of earth's history.
First, we are entering a period of the longest number of days since the last Category 3-plus hurricane has hit landfall in the US, shattering the record for the longest stretch between hurricanes hitting the United States. Seventy hurricanes hit the U.S. between 1911 and 2010. Over the last five decades, we have been hit by 5.6 hurricanes whereas the preceding five decades the average was 8.4 hurricanes. Second, a study by two ASU professors indicates that the number of severe tornadoes in recent years has dropped. Third, consider the dust bowl drought and heat waves of the 1920s and 1930s. In the 1930s, half of the states set new record highs. Since 2000, only one state recorded a record high. Or, in October 1952, the U.S. experienced the driest month in recorded history as part of a 3-year drought.
Before we jump to conclusions, let's look at the facts. Extreme weather is part of our existence on this planet. Based on data, global warming is not increasing extreme weather events.