MEMPHIS, TN (abc24.com) - Sunday storms had many of us double-checking the calendar to make sure it wasn’t spring. High temperatures soared into the 70’s in the Mid-South, and Memphis set a new daily record of 71 degrees. Record warmth and ample moisture streaming northward from the Gulf of Mexico were perfect ingredients for severe weather. However, many people are scratching their heads wondering why severe weather is starting so early for the Mid-South.
ABC 24 Meteorologist David Still said, “Obviously, we expect tornadoes during our severe weather season in April and May. This year, one of the main driving features is La Niña.”
A La Niña year means sea surface temperatures in the eastern tropical pacific are cooler than normal. Changes in the ocean can happen on average every 3 to 5 years and it has big impacts on weather patterns. A La Niña pattern will typically mean above normal temperatures and an earlier severe weather season in the South.
“The last time we had a good set up like this was in 2008 when we also had several high impact January events,” Still explained. “Quite a few of those outbreaks during La Niña years were squall line events like we saw last night.”
The optimistic pattern from past La Niña years has shown that typical stormy months, April and May, were quieter and less active with severe weather. So, if 2012 follows the same pattern, maybe the spring season will be an uneventful one.