Science Source

Spatial trends in United States tornado frequency

States that:
- Severe thunderstorms accompanied by tornadoes, hail, and damaging winds cause an average of 5.4 billion dollars of damage each year across the United States, and 10 billion-dollar events are no longer uncommon
- This overall economic and casualty risk has prompted public and scientific inquiries about the impact of climate change on tornadoes
Shows that:
- National annual frequencies of tornado reports have remained relatively constant, but significant spatially-varying temporal trends in tornado frequency have occurred since 1979
- Negative tendencies of tornado occurrence have been noted in portions of the central and southern Great Plains, while robust positive trends have been documented in portions of the Midwest and Southeast United States