A scientist in Wisconsin has come up with a factor that ties together an extreme flooding in Tennessee last year with the tornado outbreak this year in Alabama:
But the fascinating part is that the change originates in the western Pacific, about 9,000 miles away from the intense storms in the U.S. midsection, Martin says.
The mechanism that causes the storms originates during spring or fall when organized complexes of tropical thunderstorms over Indonesia push the subtropical jet stream north, causing it to merge with the polar jet stream.
The subtropical jet stream is a high-altitude band of wind that is normally located around 30 degrees north latitude. The polar jet stream is normally hundreds of miles to the north.
Martin calls the resulting band of wind a “superjet.”
Recognizing the conditions should now put meteorologists on alert.