When watching NBC2 News during the rainy season you might notice when lightning is plotted on the radar map, sometimes the bolt is yellow and sometimes the bolt is white (though it can appear blue on your TV screen).
The reason for the color difference is because of what each bolt is showing. Yellow lightning bolts point out negatively charged cloud-to-ground lightning strikes while white (or what can appear as blue on your screen) show positively charged cloud-to-ground lightning strikes.
Negatively charged lightning strikes make up the overwhelming majority of bolts that hit the Earth (it’s greater than 90%). They come from the bottom of the thunderstorm cloud where negatively charged particles tend to gather. On First Alert Live Doppler Radar, they’re identified with yellow lightning bolts.
Positively charged lightning is rarer, but stronger. They’re marked on First Alert Live Doppler Radar with white bolts (that can look blue on your screen).
Something to remember when discussing lightning is that most of the time, the Earth’s surface has a slight negative charge. That changes when a thunderstorm is nearby, as the negatively charged base helps to make what’s below it on Earth positively charged. Away from the base of the storm though, the Earth’s surface keeps its negative charge. That makes positively-charged lightning possible as the positively-charged upper part of the storm is nearby.
One last note on lightning is that intracloud lightning (bolts that stay in the clouds) are not marked on our radar maps because they do not strike the surface of our planet.
Tags: Weather blog