How exactly lightning forms is still open for debate. The most commonly accepted theory is that electrons are stripped off colliding ice particles caught in a thunderstorm’s updraft. Once these particles lose an electron, their net remaining charge becomes positive. These positively charged particles will rise high into the upper most part of the thunderstorm where they tend to collect. Conversely, other particles in the cloud acquire an electron after the collision and as a result, their net remaining charge is negative. The negatively charged particles tend to collect at the base of the cloud.


