There are a few items to consider when making a forecast for the winter season but it appears the upcoming year will be quite different than the last.
First, I look at trends and this summer has been quite wet. Last summer we were stuck in a drought until Hurricane Irene came along in late August. So what has caused our summer to be different? The location of ridges and troughs in the upper levels of the atmosphere is a good starting point. Last year we were stuck under a dry ridge while a trough of low pressure has been dominant in the weather picture. We have been transitioning to El Nino, which is a warming of the Pacific Ocean equatorial water. Last year we were solidly in a La Nina event. This transition can give us a hint as to where the colder and warmer areas will develop as we get deeper into the El Nino event.
Second, the El Nino event is usually associated with colder and wetter than normal conditions across the Southeast. Two significant El Nino events since 2000 have brought below normal temperatures and more snow than usual to our area. Those two years were 2002-2003 and 2009-2010. It would certainly be a contrast with last year when our area averaged as much as 4 to 5 degrees above normal with no snow or ice of consequence.
Third, the long-range computer models are singing a different tune this year. Last year in late summer most of the models which look ahead for several months were indicating a warmer than normal winter and they were right. This year the models are indicating a colder and stormier pattern for the Southeast.
Of course, a lot of things could happen over the next few months to change that forecast. I'll give another update later in September.