Inside the Storm: The Science of a Lightning Strike

Understanding what’s happening inside a storm helps you anticipate better photos. You don’t need to be a meteorologist, but it pays to know the basics.

1. Charge separation

Within a thundercloud, rising ice crystals and falling graupel rub together, transferring electrons. The top becomes positively charged, the base negative.

2. Stepped leaders

When the electric field grows strong enough, invisible channels of ionized air—leaders—reach toward the ground in steps too fast for the eye.

3. Upward streamers

Objects on the ground, including towers or even your tripod, send positive streamers upward. When one connects with a downward leader, a complete path forms.

4. Return stroke

That’s the brilliant flash you see. Current surges upward, heating the air to about 30,000 K. Multiple return strokes can happen along the same path within fractions of a second.

5. Implications for photography

Most of the light occurs in that first or second return stroke. A well-timed trigger aims for that moment. Knowing storms pulse in cycles helps you plan sequences and exposures.

Lightning is both physics and art—once you see the rhythm, you can almost feel when the next bolt is coming.