Spawning Particles across a random area

Could anyone give me some pointers on creating an effect where a bolt of lightning spawns from a random spot within a vector and arcs towards a central point?

Something similar to the boost effect from F-Zero GX?

Or the stealth effect from Metal Gear Solid 2?

This is being created using a beam emitter, which apparently cannot simply make the source of the beam cull to the ground around it from Cascade, so I’m looking to use a blueprint system or something similar to create the effect by attaching the target to the object the lightning is arcing to and spawning the source in a random area culled to the ground.

My current beam effect is a single arc from start to finish.

I was thinking I’d use the blueprint to spawn them as needed since I can’t make the source of the beam cull to the ground from within cascade.

I hope what I’m asking makes sense. I’d appreciate some pointers or references for this. I’m not that familiar with blueprint scripting yet so I’d appreciate the help.