By Michael Laches
In Holly Springs, winter means cold weather and, if we’re lucky, it sometimes means snow. But, for this southwestern Wake County town, winter rarely means meaningful snow. Still, the local snow lovers will continue to dream, but not just about white Christmases. They dream about white anything until the inevitable white bloom of the Bradford Pear trees in late February. Of course, any hint of snow can also produce a supermarket onslaught, but that’s another story. To connect us to the science of it all, we recruited Chief Meteorologist for ABC11/WTVD-TV and Holly Springs resident, Don “Big Weather” Schwenneker who has generously offered his expertise and perspective.
First of all, Schwenneker noted that working a snow event is not a lot of fun for TV meteorologists. When it snows, they alternate shifts, 12 hours on and 12 hours off.
“WTVD is very good about making sure I don’t have to drive in the snow, so when I’m not on TV, I am in a hotel within walking distance of the station safely tucked in. Though I’m safe it does stink for my family. I never got a chance to play in the snow with my kids in Holly Springs. I’m very lucky to have great neighbors though. [My neighbor] Dr. Mark Pisano would get out and shoot snow pics and send them to me so I could feel part of the excitement. And winter snow can be exciting, but how many times do we actually get snow?” he asked.
Schwenneker looked back at the last 25 years and noted there has been at least a tenth of an inch of snowfall at RDU (i.e., the official reporting station for the National Weather Service, or NWS, in this area) 82 times. That’s about three times per year. The largest and most memorable of these happened on January 25, 2000.
“[Holly Springs] saw 17.9” of snow in one day. We’ll come back to that in a bit,” he said.
Schwenneker noted that the NWS has a secondary weather station in Apex—the closest station to Holly Springs. During the same 25-year period, that station recorded 1/10 of an inch of snow 72 times or 10 times fewer than RDU. This is illustrative of how small distances can make a big difference in snowfall totals around the Triangle.
“We are in a part of the country that can see big differences across just a few miles. Part of it has to do with where we are in latitude on the Earth’s surface. Part of it has to do with mountains to the west and how they affect systems moving west to east. And, a big part of it has to do with a giant area of water just to our east, known as the Atlantic Ocean, and the strange things it can do to our weather,” he explained.
According to Schwenneker, our ancestors saw the differences in weather patterns and traveled along lines where the weather was just a little bit better. Those paths would turn into wagon trails, country roads, and, eventually, major highways. One of those highways is on Holly Springs’ northern border. You all know it as US-1. It still serves as a dividing line and is used today by weather forecasters. Snow tallies to the north of US-1 are typically higher and those to the south fall off.
“By the way, that rain/snow cutoff line runs right through Wake County. It makes for some interesting ‘snow days’ for Holly Springs school children. I’ve lost count of the number of times the snow hasn’t melted in the northern part of the Wake County school district and a snow day is called. Yet our kids enjoy a sunny day with very little on the ground because those snow totals were completely different over just a few miles,” he shared.
So, what does this winter hold in store? Schwenneker said there are typically four things he likes to look at and these include the snowpack across Siberia, the Solar Cycle, the North Atlantic Oscillation or NAO, and is it a La Niña or El Niño year?
The snowpack across Siberia in northern Russia can determine how much cool air pools at the North Pole and flows down into our region.
“I also like to look at where we are in the Sun’s energy cycle. It fluctuates to a maximum and minimum over an approximately 11-year period and where we are can determine what space weather might be headed our way,” he said.
The NAO has to do with a weather phenomenon over the North Atlantic Ocean and fluctuations in the differences of atmospheric pressure at sea level. That can determine how weather systems flow across the US.
“Finally, we come to La Niña and El Niño. In an El Niño year, the water in the eastern Pacific warms unusually around Christmas time. Because of its timing it was named after the Christ child, El Niño, or the Baby. La Niña is the opposite. It means the water is cooler than normal at that time of year. Depending on the temperature, different winter systems can head our way,” Schwenneker shared.
La Niña years usually mean warmer than average winters in North Carolina. They also mean less than average precipitation and can lead to drought situations. During this winter, we are in a La Niña year so Schwenneker’s forecast is predicting lower than average snowfall totals and above normal temps.
“That being said, remember that 17.9” of snow in 2000? That happened in a La Niña year. Though the pattern calls for less snow, a rogue storm can always bring ‘the big one’ and they are extremely hard to forecast, especially at long range,” he said.
So, will it snow this year?
“Statistically I can say yes, maybe once or twice. Will it be over 6 inches? Probably not. But if one of those rogue storms rolls through, we could. As Lloyd Christmas says in Dumb and Dumber, “So you’re telling me there’s a chance…”
Yes, Holly Springs, there is always a chance.
