Thanks to another strong La Niña, the cooler than normal sea-surface temperature event in the south-central Pacific Ocean, global weather patterns were extreme in 2011.
January through early April was the snowiest such span in recorded history for 5,500 cities throughout the U.S. More than 3 feet of snow was measured in January alone in New York City’s Central Park.
In Chicago, more than 900 drivers were trapped by 6- to 8-foot snowdrifts for more than nine hours on Lakeshore Drive along Lake Michigan during an early January blizzard.
When the all-time record U.S. snowpacks melted a month later than usual, we saw the worst flooding on record along parts of the Mississippi River in May after a series of torrential downpours.
The Mississippi expanded to six times its normal width causing severe rural flooding after officials created a “planned disaster” in order to save Baton Rouge, La., and New Orleans from Katrina-like floodwaters.
The biggest weather story this past year in the U.S. was the record number of “killer tornadoes” in April and May.
On April 14-15, in less than 48 hours, there were a record 206 tornadoes in 16 states reported. At least 38 people died.
On April 27, Tuscaloosa, Ala., was hit by a powerful tornado that killed dozens of people and destroyed hundreds of homes and businesses.
On May 22, the largest tornado observed in the U.S since the 1930s devasted Joplin, Mo. The twister killed 162 people and caused more than $8 billion in damage.
On June 1, three rare Massachusetts tornadoes killed three people and caused millions of dollars in property damage.
The summer was the hottest and driest such period on record in Texas. Many towns ran out of water and losses in crops and livestock exceeded $5 billion. Another $1 billion was lost in early September near Austin, Texas, from a wildfire that was 60 miles long and 6 miles wide and destroyed more than 1,600 homes.
Arizona, New Mexico, Nevada and Florida also suffered huge forest and brush fires in 2011. The fires in Arizona were the worst in the state’s history.
Elsewhere, Canada and Mexico had huge fires in 2011. In late December, enormous fires in northwestern Italy killed dozens of people and destroyed hundreds of homes.
An ongoing severe drought continued at year’s end to kill thousands of people in a 900,000-square-mile area of northeastern Africa.
Hurricane Irene on Aug. 27 spared New York City, but caused the worst flooding in Vermont since 1927. More than 10 inches of rain fell in central Vermont in less than 36 hours.
Just two months later, shortly before Halloween, the biggest early season snowstorm in at least 400 years buried western New England. Several towns in the region had more than 3 feet of snow.