The accuracy of tornado forecasting has improved in recent decades, thanks to advances such as weather satellites, more sophisticated radar, and the use of supercomputers to crunch data. That's all enabled scientists to predict tornado outbreaks - that is, occurrences of multiple tornadoes, all spawned by the same weather system - as much as seven days in advance.
But now, a just-published study in Environmental Research Letters gives hope for a future in which scientists may be able to foresee tornado outbreaks months in advance, based upon ocean surface temperatures thousands of miles away.
NEWS: Extreme Tornado Outbreaks Becoming More Common
In the article, scientists from the National Oceanic and Atmospheric Administration and the University of Miami explain how patterns in the spring phases of the El Niño-Southern Oscillation (ENSO), coupled with variability in North Atlantic sea surface temperatures, could help predict U.S. regional tornado outbreaks.
The scientists, who studied data gathered between 1950 and 2014, found that variations in ENSO phases were linked to distinct patterns of tornado outbreak probability.
The strongest tornado connection was with strong, persistent La Niñas, consistent with the Super Outbreak of 1974 and the record-shattering tornado outbreaks of 2011, both of which occurred during strong La Niñas. The latter, in which waters in the Pacific are cooler than normal, are the opposite of El Niño, which results from a warm mass of water.
NEWS:More than 50 Tornadoes Hit the U.S. Southeast
"This is the first study to show that the most frequently occurring spring sea surface temperature patterns in the tropical Pacific and North Atlantic are linked to distinctive spatial patterns of the probability of U.S. regional tornado outbreaks," lead author Sang-Ki Lee, Ph.D., an oceanographer at NOAA's Atlantic Oceanographic and Meteorological Laboratory, said in a press release.
One of the events with the strongest connection to ocean surface temperatures was the outbreak of April 25-28, 2011, in which more than 200 tornadoes occurred throughout the southeastern United States, and caused more than 300 deaths.