First instance in the comics of The Flash's trailing lightning as literal rather than a visual effect?

Question

There are many ways to portray speed through illustration: speed lines, after-images, a blurred background, etc.

Some of these are simply artistic license upon a visual effect, rather than something literally perceived by the characters within the story (a common example, visually representing an Electro-Magnetic Pulse or otherwise invisible lasers).

For Flash, some of the above, ended-up translating into actual literal in-story powers... after-images used to illustrate movement, became a power Flash could use to project multiple copies of himself; a blurred background used to convey speed, became an actual place speedsters would go at speed.

Lightning falls in this latter category.

Lightning is tied to the Silver Age Flash's origin, name, and symbol. Yet, mostly doesn't play any other role in his powers. I'm fairly confident that even after Crisis, Barry and Wally did not count lightning as part of their power set.

Sometime during Wally's run, his speed started to be represented with crackling energy and lightning unseen by anyone else. Then at some point it became literal lightning, where he had to worry about it setting off sparks or acting as illumination. Then it became a whole other facet to the power set to the point that the CW's Flash throws lightning as an attack.

When was the first time Wally's speed was portrayed with lightning effects?

When was the first time those effects entered the story as literal lightning which could interact with the story?

Answer 1

When was the first time Wally's speed was portrayed with lightning effects?

Flash Volume 2 Issue 72 (January 1993), artist Greg LaRocque began to portray Flash's speed specifically by making the lightning parts of Wally's costume trailing lightning, still maintaining a jagged and electrical shape, and without other speed lines or a red-blur to convey the motion.

Although LaRocque started drawing The Flash when Mark Waid joined the title ten issues prior with Issue 62 (May 1992), until 72, he was still using primarily speed lines and red-blur to show Flash's speed. Although he'd inject a few jagged lines to express the trailing costume parts and the coloring would match, it wasn't clear that Flash left a trail of lightning behind. In fact, he reverts back to this after issue 72 until issue 77-79, closing out the epic "Return of Barry Allen" story arc and making the final battle more visually dynamic.

Mike Wieringo takes over as artist and adopts LaRocque's innovation in a few issues and codifying it on the cover of Issue 83 (October 1993). From then on it became a more deliberate, intentional, and increasingly exaggerated part of the Flash visual lexicon.

The conversion of the visual effect into something actually literally perceived in the world is a little tougher to pin down, but I believe it starts somewhere around Issue 93 (August 1994) as Impulse / Bart Allen and Wally interact with the Speed Force and the effects are something they can see. It is certain by Issue 95 (November 1994), because not only can Wally see the effects but love interest Linda Park can too as the Flash is becoming an energy-being.