La Nina Pattern Will Affect Winter Forecast

By Kelly Bryant – email | bio

"There are forecasts, where, well, we're gonna have a warmer than normal winter in the south this year...don't rule out the fact that there can still be the possiblility of some cold air, and even an occasional chance for snow."

You may have heard the terms, El Nino and La Nina, but the question is, what does that mean for the forecast?

first things first, the la nina pattern itself means cooler ocean temperatures, the exact opposite of el nino. When any kind of pattern changes, the weather is affected. In this case, the winter forecast.

Rex Thompson says, "We'll certainly see a vastly different winter here than we saw last year. We had many cold outbreaks, we had several snows, and a lack of severe weather."

After doing a little research on climate and different weather patterns, it turns out, ocean temperatures have a good bit to do with what happens on land. With cooler ocean temps during La Nina, three main components affect the average forecast. Without getting too scientific, the first one is that wave patterns are amplified, and in turn, change upper air patterns across North America. The second is increased blocking activity over the high latitudes. WDAM's Rex Thompson explains that when this happens, we will still see significant snaps of cold air.

"We're still gonna have those occasional surges of cold air coming in. So it's not like we're going to have a winter that there's not going to be any cold air at all."

The third component has to do with jet stream strength, the more variable that is, the more variable the weather is during the winter months. That being said, central North America typically sees more stormy weather, while the south sees a little less than normal. On top of that, we're looking at a lot of temperature variation, which typically means it'll be warmer here than anywhere else.

The National Weather Service forecast says it will be warm and dry, while other reputable forecasting offices say the exact opposite. Either way you slice the effects of La Nina, forecasting the weather sometimes goes out the window, because Mother Nature has a mind of her own.

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