There’s no shortage of weather myths and misconceptions to talk about- I’ve already debunked several! For this go around, I’ll be covering winter weather- clearing up some buzz words, and answering one of the most-requested questions I get as a meteorologist: is it going to snow?
Groundhog Day Forecast Accuracy
Since 1887, Punxsutawney Phil has been forecasting winter’s arrival- or at least attempting to. His track record isn’t the best with roughly an accurate prediction only 40 percent of the time. You’d be better off just flipping a coin with closer to 50% accuracy, but what do you expect taking weather advice from a rodent with no formal science education?
“The Polar Vortex”
It’s quite a name, one that makes headlines whenever a big blast of cold air comes down from the north! It’s nothing new as its name dates back to the mid-1800s to describe a persistent area of low pressure and cold air high up in the atmosphere at both the north and south poles.
The “vortex” bit refers to the constant counter-clockwise flow of air to keep that cold air locked in near the poles…most of the time. Sometimes during winter, that usually stable vortex weakens and becomes wavy; allowing very cold Arctic air to surge southward as the jet stream buckles into the US. This isn’t rare- but does lead to our coldest days!
The Possible Link Between Snow and Hurricane Activity
This assumption likely originates from our biggest snow on record occurring after Hugo in 1989. This was just a coincidence as there is no link between Hugo and the historic snow several months later.
But what about if we looked at the bigger picture…?
There is some research being done at my alma mater to determine what, if any, impacts an active hurricane season has the following winter. On paper it makes sense. Hurricanes and other tropical systems bring a lot of heat to the poles- taking away established cold air which winter will have to “make up” the following winter- resulting in less snow after active hurricane seasons, more snow after less active hurricane seasons.
So like a good scientist I tested my hypothesis, looking at 115 years of data we have available for Charleston.
After cross-checking the 20 winters we have seen measurable snow to the intensity of that hurricane season… the results supported that a less active hurricane season resulted in more years with snow- occurring 50% more often than winters following an active season.
So while there is a trend, it is likely not as significant as other major weather patterns that are proven to impact snowfall amounts.
By the way, the 2019 Atlantic hurricane season was above average- draw your own conclusions there, but certainly don’t think just because we saw a hurricane hit us means we’ll be blessed (or cursed) with snow.
Storm Team 2 Meteorologist David Dickson