MEMPHIS, TN (WMC) - There's an old wives' tale that a hot, humid summer night can generate lightning without a thunderstorm is called "heat lightning."
The term heat lightning is actually used to describe lightning from a distant thunderstorm that's too far away to see the actual cloud-to-ground flash or to hear the accompanying thunder.
The term "heat" in heat lighting has little to do with temperature.
Since heat lightning is most likely to be seen in association with the warm season, the term "heat" may have been used because these flashes are often seen when surface temperatures are warm.
Sometimes mountains, hills, trees, or just the curvature of the earth prevent the observer from seeing the actual lightning flash.
Instead, the faint flash seen by the observer is light being reflected off higher-level clouds. Also, the sound of thunder can only be heard for about 10 miles from a flash.
So can you ever have thunder without lightning? Meteorologist Nick Gunter has the answer to that in this breakdown.