I'm hearing that a "La Nina" is developing that could help stretch this year's hurricane season deeper into the fall. Does La Nina also increase the odds of a warmer, drier winter in North Carolina?
Posted September 15, 2007
MIKE MOSS SAYS: Gary, You are correct that a La Nina development is underway and is thought likely to continue in the next few months, and also that La Nina tends to correlate with enhanced Atlantic basin tropical cyclone activity.
As for winter in North Carolina, the tendencies you mentioned are the correct ones and are roughly opposite those of a typical El Nino pattern. We tend to have above normal temperatures more frequently under La Nina conditions, along with fewer significant precipitation events and slightly lower than normal precipitation totals. However, it's worth noting that these are fairly small anomalies for our area and that La Nina is also known for significant instability in large scale wintertime patterns across the U.S. - that is, on average it may be associated with certain distributions of higher and lower pressure and the temp/precip patterns associated with that, but with frequent pattern shifts and breakdowns that, for a few days at a time, allow for major changes such as very strong cold air outbreaks into the eastern U.S. - you can explore some of the average tendencies associated with La Nina and El Nino at this address: