Despite the tornadoes that occurred on February 24, including the first deadly tornadoes of the year, the United States is running behind schedule in the tornado numbers department this year. Will the quiet trend we have seen thus far continue as we head into April, and May?
The country just went through a major pattern change, with a more persistent parade of storms digging into the Southwest before strengthening over the central United States. Meanwhile, a strong blocking pattern in the western Atlantic (-NAO) is allowing the parade of storm systems to drop cold fronts deep into the South. This limits the flow of warm, moist air from the Gulf of Mexico into the country… and limits the violent storm formation that spawns tornadoes.
While the pattern over the western half of the country could be conducive to a more active tornado regime, the blocking pattern over the Atlantic and eastern U.S. is keeping the overall instability low across the U.S. by shutting down the transport of warm, moist Gulf of Mexico air into the U.S. This will probably help limit tornado production over at least the next 1-2 weeks.