Here is my OLD first 13:

Jagged bolts of lightning forked across the rolling banks of char above him towards the distant city of Jenoah like multicolored threads of a vast spider web . He watched uneasily as the electric-blue, bright white and citrine flashes radiated within the blanket of engorged clouds.
His loose pantaloons flapped against his legs and his shirt ballooned about his body as winds snatched his cloak as if trying to fling him from his rocky perch.
Power coalesced above the city drawn by the battle beneath it and the elements above responded as if the Gods of Air, Light and Fire battled for supremacy.
The thunderheads broke and Water joined the fray, black rain pelting down before it was whipped nearly sideways by the howling winds.

VERSION 2:

Thanairen bristled at the ebb and flow of the battle in the distant city. _Dear Ilumni, I beg you, bring my brother victory,_ he prayed. He gritted his teeth as if in response, jagged bolts of citrine and emerald lightning skittered across the banks of char-colored clouds, drawn to the raging conflict.

His loose-fitting clothes flapped about his body, buffeted by storming winds. Eddies snatched at his hooded cloak in an effort to fling him from his rocky perch high above the vast black plains and forests.

Elements of Mater, the essence of all Creation, coalesced above Jenoah summoned by the two men battling within its walls. The power of the elements roiled across the sky as if the Gods of Air, Light and Fire battled for supremacy.

VERSION 3

Thanairen bristled at the ebb and flow of the battle in the distant city. _Dear Ilumni, I beg you, bring my brother victory_, he prayed. As the thought crossed his mind, he licked his suddenly dry lips before taking a quick glance around him. _Calm down man, stop jumping at shadows._ Yet here in the world of Hydae, the ominous shadows and the Dark held sway.

Just then, jagged bolts of citrine and emerald lightning skittered across the banks of char-colored clouds, drawn to the raging conflict in Jenoah. His stomach fluttered and he gritted his teeth at the dark sky. If not for Irra he would not be on this forsaken ledge exposed to the angry elements.

Like some intricate conspiracy, storm winds kicked up and flapped his loose-fitting clothes about him.

Which one do you like?

The imagery and command of language are great. I would just tone it down a bit. The first line:
"Jagged bolts of lightning forked across the rolling banks of char above him towards the distant city of Jenoah like multicolored threads of a vast spider web."

Pretty writing, but I'd drop a few descriptors. I think "rolling" could go, as well as "Jagged". The word "bank" describes some kind of slope, and its plural so we can get a sense of multiple banks which the word rolling suggests. Jagged can go because you describe it as being forked, which suggests jaggedness and also because you can assume the reader knows what lightening looks like. So it would be like this:

"Bolts of lightning forked across the banks of char above him towards the distant city of Jenoah like multicolored threads of a vast spider web."

This is lighter and I think packs more punch.

I think a few more sentences could benefit from the same attention.

I wanted to weigh in without reading the other comments so that if there are any common threads in the crits, you can assess them a bit more objectively. You have an obvious gift for description (exposition). By cutting it down and getting right to the MC and his/her goals and obstacles this opening would be vastly improved. So, below, in parentheses are my crits:

Jagged bolts of lightning forked across the rolling banks of char above him (him who? Give us his first name)towards the distant city of Jenoah (Here the sentence drones on and needs to end.) like multicolored threads of a vast spider web .
(What if you re-wrote it with a less-is-more approach? Something like: Chad bristled at the spider web of lightning forking accross the rolling char above him toward Jenoah.)

He watched uneasily (agents and editors hate, and I mean HATE, "ly" words so cut them wherever possible.)as the electric-blue, bright white (too wordy--all weather and no goals) and citrine flashes radiated within the blanket of engorged clouds.

His loose pantaloons flapped against his legs and his shirt ballooned about his body as (this is the second and third "as" in your opening and later, you use a fourth!) winds snatched his cloak as if trying to fling him from his rocky perch. (Why not: The wind snatched his cloak, flinging Chad from the safety of his rocky perch.)

Power coalesced above the city drawn by the battle beneath it and the elements above responded as if the Gods of Air, Light and Fire battled for supremacy.
The thunderheads broke and Water joined the fray, black rain pelting down before it was whipped nearly sideways by the howling winds. (All of this can be cut and re-worded to show us your MC's goal and key conflict. How does MC feel with the foreshadowing of the angry weather as a symbol of the battle beneath and why and how is MC caught up in or affected by the battle beneath.)

Terry, something else you should know. Agents (for example, Donald Maas and many others) have a running joke with their first-level readers (the people they hire to screen requested manuscripts). The joke is: "Weather opening" followed by a quick toss in the rejection pile. Weather as a foreshadowing method is fine, especially later on once we've bonded with your main character, but it is a first-time rookie mistake which plagues otherwise good manuscripts. Stephen King gets away with it because he is money and is a proven money maker for his agent. I urge you to read any one of Donald Maas's primers on novel writing and then re-work the opening. You can write. It's a matter of structure, so go for it--you can do it.

Wum