How often do flakes follow thunder? The scientists at the State Climate Office ran the numbers. Science!
Along with a diverse variety of frozen precipitation, it’s not unusual to see a thunderstorm during the winter in North Carolina. At some point, that gave rise to the proverb that if you hear thunder during the winter, it will snow in 7 to 10 days. It makes some sense considering that weather systems generally take about a week to move across the country, so a strong cold front that produces thunderstorms is likely to be followed by another system within the next 10 days. But here in North Carolina, where snow is never a guarantee, how often is thunder followed by flakes?
Source: Winter Outlook 2013-14: Forecasts from Winter Folklore | State Climate Office of North Carolina