Thunder in the winter: Will we see snow in 7-10 days?
RALEIGH (WTVD) -- Here we go again. A storm moved through bringing thunder with it, so everybody starts saying it's going to snow in the next 10 days. But is that old saying based in scientific fact?
I previously wrote an article about snow and if, indeed, it does fall 10 days after thunder in the winter. I looked at every snowfall in the past 50 years, went back 10 days, and looked to see if it thundered. Only 2.9 percent of the time it did.
Several of you, however, pushed back saying, 'Nay, nay, Big Weather. Nay, nay.' They felt the research was flawed. They suggested I look at how many days it thundered in the winter, go forward 10 days, and see if it snowed during ANY of those days.
Well, our crack research team (my wife and I) went back to the records and here is what we found:
I logged on to the NC State Climatologist's office and looked at the last 50 years of weather reports from RDU, 1966-2016. The total number of weather reports totaled 411,596! It took me a few days to go through that, even with a fast computer.
I looked at every time thunder was reported at RDU in the months of December, January, and February (those three are winter months in Meteorology). I also added in March because winter doesn't end on the calendar until then, and we do see snow sometimes.
There were 129 times it thundered in those months. Five times it snowed 10 days later. That means it snowed 3.9 percent of the time, just 1 percent more than my original findings. But a funny thing happened on the way to those numbers.
I was discussing this with one of behind the scenes folks and she said, "I thought it was supposed to snow sometime in the next 10 days, not exactly 10 days out."
Well, that's a horse of a different color. So I went back to the numbers (more research can always be done).
Here's what they showed.
Out of the 129 times it thundered in those months, it snowed 25 times within 10 days. That upped the percentage to 19.4 percent of the time. That's almost a 1 in 5 chance of snow sometime after thunder in the winter.
I was a bit surprised it was that many, but it does make sense.
For thunder to happen you have to have all kinds of active weather in the atmosphere, and with precipitation averaging every three days in our area during the winter, there are lots of opportunities for thunder -- and some snow may be next.
I know more research can still be done: looking at different stations, looking to see if freezing rain or sleet also falls, etc., but I'm done for now.
It's funny. Those old weather sayings tend to have some truth in them, or they wouldn't have stuck around so long.
