El Niño forms, impacts on the Carolinas
JANUARY 2019 UPDATE
Sea surface temperatures in the central and eastern equatorial Pacific ocean have warmed to above average. This means we have El Niño in place after spending much of the fall in neutral conditions with sea surface temperatures near average.
The average sea surface temperatures in the equatorial Pacific are forecast to remain above average through the spring, and possibly the summer. However, the overall trend is for the sea surface temperatures in the equatorial Pacific to gradually cool, meaning a slowly weakening El Niño through the first half of the year.
The odds that El Niño persists through the winter are quite high at 90% and remain reasonably high with a two in three chance of it persisting through the spring. By the summer, there is virtually a 50/50 shot of El Niño persisting, with the odds being nearly equal that the equatorial Pacific shifting to a neutral phase. The odds of a La Niña developing are less than 10% through the end of summer.
So, what does an El Niño mean for the Carolinas. For the winter, it means that we are expecting a wetter and cooler setup. However, this does not necessarily guarantee snow. Even though the overall pattern for the winter will be wetter and cooler, there will still be occasional days where we are warmer or drier. Remember, to get snow, we need the cold air and precipitation at the same time. The most common setup for this to occur is a storm system forming off the Carolina coast, funneling moisture from the ocean and cold air from the north at the same time.
If El Niño sticks around for hurricane season, the good news is that it helps diminish the number of hurricanes we see form. This is due to stronger upper level winds that will shear apart tropical systems as they travel across the southern basin of the north Atlantic. Again, just because we'll see fewer hurricanes, it doesn't mean we'll be able to let our guard down. It only takes one hurricane to make it a bad season for us.