Will La Nina's end bring changes to Carolina weather?

Photo courtesy of the National Weather Service
Photo courtesy of the National Weather Service

CHARLOTTE, NC (WBTV) – Only recently has La Nina officially come to an end.  For some, that will mean better chances of warm, wet weather.  Others will be drier and cool.  What about the Carolinas?  Could this change in the Pacific Ocean give us some insight into what to expect this summer?

First, just what exactly are we talking about when we say "La Nina?"  La Nina is the name given to the cool phase of the El Nino - Southern Oscillation (ENSO).  In the La Nina phase, cooler sea surface temperatures prevail in the central and eastern tropical Pacific Ocean.  

We know that warm air and moisture are the two key ingredients in the formation of showers and thunderstorms, so the cooler temperatures mean a reduction in convection in that part of the Pacific.  North Carolina State Climatologist Ryan Boyle says that reduction in convection causes worldwide changes in jet stream patterns.  "During La Nina events in the winter, the average path of the jet stream over the eastern US is generally less amplified and more zonal," says Boyle.  It's a setup that results in storm tracks on the western side of the Appalachians, keeping us in a dry pattern.

Photo courtesy of the National Weather Service

And as we head into the warm season?  Boyle says the end of La Nina doesn't mean much as we move into summer.  "More important for us is the strength and extent of the Bermuda High, which isn't well correlated with ENSO phase or intensity."

So any hints of what that Bermuda High might do?  It doesn't look that way.  The Climate Prediction Center has equal chances for above, below or near normal precipitation.  Boyle says that's a scientific way of saying we don't have a clue how this summer will unfold.

At this point it looks like we'll just have to wait and see!