Extreme weather events can cause widespread damage resulting in billions of dollars of losses. Recent events, such asblizzards, hurricanes, and droughts have been exceptionally devastating as a result of several environmental factors. The convergence of several weather systems and the right atmospheric conditions sometimes result in the "perfect storm." This issue examines the factors behind catastrophic weather. It explains El Nino and La Nina, which are instigators of many unusual climactic events around the globe. These phenomena impact ocean temperatures, wind patterns and other atmospheric conditions. Other intense storms, such as Hurricane Sandy, result from the interaction of low pressure systems, which affect the direction and strength of the storm.