A few months back, it looked like an El Niño was going to take over the global weather system this winter. El Niño patterns typically bring stormy weather to the southern U.S. and drought to places like Australia. But this morning, the National Weather Service canceled its El Niño watch. It just fizzled out, says Mark Halpert, deputy director of the Climate Prediction Center in College Park, Maryland. He spoke with NGM senior editor Peter Miller.
Has this ever happened before?
In our limited historical record, it’s unprecedented. We haven’t seen a case where it has ramped up toward an El Niño in late summer and then just petered out.
For an El Niño to develop, you need to see the atmosphere reacting to changes in the central Pacific Ocean. That area had warmed earlier this year, but, for whatever reason, the ocean and atmosphere didn’t begin to reinforce each other, and the ocean went back to neutral conditions.
What does that mean for our weather this winter?
It means that our weather will be driven by phenomena that typically have shorter time scales. When El Niño sets up, it will reliably provide forcing through the winter. When you’re dealing with something not as consistent, then really all bets are off.
The last El Niño we had was three years ago, wasn’t it? The winter we had Snowmaggedon on the East Coast?
Yes, we had a strong El Niño in 2009-2010 that resulted in multiple big snowstorms along the East Coast. The El Niño contributed the storminess and the moisture, but the final ingredient you need for snow was cold air. That was the winter we saw a remarkable negative or cold phase of the Arctic Oscillation. We had quite the delivery of cold air throughout much of that winter.
Does the fizzling out of El Niño have anything to do with the weird behavior of Hurricane Sandy?
Not really. What happened with Sandy was caused by another system coming down out of the north and west that was timed, so to speak, to interact with Sandy and steer it back inland. El Niños, in fact, typically suppress hurricanes in the Atlantic. If we’d seen El Niño impacts at the time, we might not have seen Sandy at all. When the storm was being formed down in the Caribbean, we would have seen increased wind sheer in the atmosphere. Sandy might never have gotten going.