Why April Is the Deadliest US Tornado Month
April averages 180 US tornadoes and has produced the deadliest tornado outbreaks in history. The 1974 Super Outbreak, 2011 Super Outbreak, and Palm Sunday 1965 all struck in April.
The Numbers
| Month | Avg tornadoes | Historical avg deaths |
|---|---|---|
| January | ~35 | 7 |
| February | ~40 | 15 |
| March | ~85 | 25 |
| April | ~180 | 60 |
| May | ~270 | 40 |
| June | ~240 | 15 |
Notice: May has MORE tornadoes on average than April, but April has more deaths. The reason: April's tornadoes tend to be violent, long-track events that occur over more populated areas, while May's are more diffuse across the Great Plains.
Why April Is So Deadly
1. Dixie Alley Is Fully Active
By April, the Southern US atmosphere has warmed enough to support daily severe weather. But the jet stream is still active enough to provide strong wind shear. This combination produces long-track, violent tornadoes across the Deep South - the most lethal type of tornado in America.
2. Tornado Alley Season Is Ramping Up
April marks the start of peak Great Plains tornado activity. Oklahoma, Kansas, and northern Texas begin seeing major supercells. Some of the most violent Great Plains tornadoes in history have occurred in April.
3. Nighttime Tornadoes Are Common
Roughly 40% of April tornadoes occur at night in the Southeast, dramatically increasing fatality rates. More on nocturnal risk ->
4. The Setup for Outbreaks
Every major April outbreak has featured the same atmospheric setup: deep low-pressure system, warm Gulf moisture, cold air behind a strong cold front, extreme wind shear. This combination happens most frequently in April, less often in May and June.
Deadliest April Tornado Events
- April 25-28, 2011 Super Outbreak - 360 tornadoes, 324 killed. April 27 alone: 216 tornadoes, 316 killed.
- April 3-4, 1974 Super Outbreak - 148 tornadoes, 335 killed
- April 11, 1965 Palm Sunday - 47 tornadoes, 271 killed
- April 3, 1957 Dallas - F3 near-miss on downtown Dallas
- April 26, 1991 Andover, KS F5 - 17 killed at Golden Spur
What Makes April Different Meteorologically
In April, the jet stream is still active and moving further south than it will be in May-June. This provides strong wind shear across the Deep South. Simultaneously, the Gulf of Mexico has warmed enough to feed deep moisture inland. The result: outbreak conditions can develop from the Gulf Coast to the Great Lakes on the same day.
By late May, the jet stream shifts north and severe weather becomes concentrated in the Great Plains. By June, most of the Southeast becomes too stable for widespread outbreaks. April is the sweet spot where both regions are simultaneously vulnerable.
How to Prepare for April
- Late March: Test NOAA weather radio, review shelter plan with family
- Early April: Run a household tornado drill
- Throughout April: Pay attention to SPC outlooks - PDS Watches especially
- Have shoes and phone charger next to your bed during peak-risk weeks
- Storm shelter considered? April is when it matters most
April in a Warming Climate
Research since 2018 suggests April tornado activity is shifting eastward - fewer events over the western Great Plains, more over the Mid-South. This concentrates April's deadly potential over Dixie Alley states already vulnerable to nighttime, mobile-home tornado deaths.
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