| Rank | Event | When Occurred | Event Description | More Information |
| 1 | Tornado Super Outbreak | April 25-28, 2011 | On April 25-28, the largest tornado outbreak ever
recorded (343) leveled the southeast U.S. There were 199
confirmed tornadoes and 316 tornado-related fatalities on
April 27th, both are modern-day records for a 24-hour
period. | Spring
Extremes Special Report |
| 2 | Southern Drought | Throughout 2011 | Extreme, persistent heat, combined with minimal
precipitation, defined the most "intense" one-year drought
on record - by several drought metrics - for large
portions of the Southern Rockies, Southern Plains and into
neighboring Louisiana. The calendar year 2011 was the
driest on record for Texas. | Spring
Extremes Special Report |
| 3 | Joplin Tornado | May 22, 2011 | An EF5 tornado tracked through the heart of Joplin
claiming 158 lives. It was the deadliest tornado since
1947 and seventh deadliest in U.S. history. It is also the
costliest single tornado in U.S. history. | Spring
Extremes Special Report |
| 4 | Mississippi and Ohio River Flooding | May | Much of the central U.S. received up to three times of
normal spring rainfall, and four Ohio River states (KY,
OH, PA, WV) had their wettest spring on record. Record and
near-record flood stages occurred throughout the lower
Mississippi and Ohio River systems, many exceeding the
legendary floods of 1927 and 1937. | Spring
Extremes Special Report |
| 5 | Hottest Statewide Summers on Record | Summer (Jun-Aug) | Texas, Oklahoma, New Mexico, and Louisiana had their
warmest summer on record in 2011. Oklahoma and Texas both
exceeded the record for the two warmest summer statewide
temperature for any state in the Union (OK 1st and TX
2nd). | Summer
National Report |
| 6 | Hurricane Irene | August 20-29, 2011 | The first landfalling US hurricane since 2008, Irene
made 3 landfalls along the Atlantic coast, disrupting
power to over seven million homes and businesses and
spawning numerous tornadoes. At least 45 fatalities
occurred with over $7.3 billion in damages. | August
Tropical Cyclones Report |
| 7 | North Plains / Midwest Flooding | June | Meltwater from an above average winter snowpack,
combined with warm spring temperatures and above average
precipitation made its way into the rivers and streams of
the Missouri River system. Record flooding resulted across
the Northern Plains and Upper Midwest in June. | Spring
Extremes Special Report |
| 8 | U.S. Wildfire Season | Throughout 2011 | The Spring-Fall wildfire season across the southern U.S.
broke numerous records. Texas had its most destructive
fire of the modern record - destroying over 1,500 homes -
while Arizona and New Mexico had their largest. | Spring
Extremes Special Report |
| 9-tie | Tornado Outbreak | April 14-16, 2011 | The outbreak covered a swath of land from Oklahoma to
North Carolina and at the time was the largest tornado
outbreak on record, being surpassed two weeks later.
Thirty tornadoes were verified in North Carolina, breaking
the state record for the number of tornadoes during one
day. | Spring
Extremes Special Report |
| 9-tie | Tropical Storm Lee | September 1-11, 2011 | Lee made landfall on the parched Gulf Coast, where
impacts were major, and mixed (drought relief, but with
severe local flooding). The remnants' slow churn across
the already-soaked Ohio Valley and Northeast brought
continued misery the region, and floods of historic
proportions to Binghamton, NY and Hershey, PA. | September
Tropical Cyclones Report |