How do bulk regions of clouds conduct charges into a lightning bolt?

It's easy to find explanations of the theories of charge accumulation in clouds during storms, as well as ones describing suspected processes leading to lightning channel formation. What I have yet to encounter is any theory describing how a large region of a cloud can be conductive enough (for any duration, long or short) to allow charges to be conducted into a lightning bolt channel.

In other words, how would the ice or water particles that supposedly collect charge move these charges toward a strike channel without some kind of conductive plasma between them? Is there plasma that reaches into large cloud regions? If so, how does it form and what might be the lifetime?

• It's not that the cloud becomes conductive, it's that it's a big insulator which allows for the accumulation of charge in regions. If the clouds were insulators, they would almost never discharge through lightning because charge would never accumulate enough to breakdown the atmosphere. Jun 11, 2018 at 13:33
• @honeste_vivere, I'm assuming you meant 'If the clouds were conductors ...' ... Jun 12, 2018 at 2:54
• (sorry still getting used to the site) ... yes, that would seem to hold if the whole cloud were conductive, but that's not what I'm asking. Let's assume that, prior to a strike, all the air around the charged ice or water particles is not a plasma (not conducting). It appears that the average lightning bolt might have a channel diameter on the order of several cm. But the negatively charged region at the base of a storm cloud could easily be a square kilometer. So how might such a large region of charged particles instantaneously conduct into a strike? Jun 12, 2018 at 3:05
• Yes, sorry... I meant to say "If the clouds were conductors, they would almost never discharge..." I think you may be missing my point a little. That the cloud is a giant insulator means lots of charge can accumulate over very large regions, which causes a large electric field. If the field becomes large enough, it can cause an electrical breakdown of the atmosphere, which allows the excess charge to discharge through a lightning bolt. It's the field that starts all of this, which stems from its source, the accumulation of large amounts of charge. Jun 12, 2018 at 13:35