This is a very powerful, evocative picture. Comparing lighting to a dragon is especially true for asian dragons, with their endless coils and winding tails. In my mind's eye this gives the whole piece a very oriental feel.
Now, in the poem's description you mentioned you were not sure about punctuation. I think it's quite alright but I'd like to point out a couple other things.
First and foremost, the length of the poem. You used the 5-7-5 syllables scheme. That's OK, though you should be aware that that is not the most important feature of a haiku, nor is it a defining characteristics according to both Japanese and English contemporary standards. There's an argument to be made that "syllables" is not the correct metric here, as (traditional) haiku have 5-7-5 on ("sounds"), not syllables. An on is not the same as a syllable, and therefore these cannot be used interchangeably. *mcdermid wrote a great article elaborating on this: Counting Syllables.
Now... With the constraint of a set number of syllables out of the way, I would suggest getting rid of all non-essential information. The key to writing good haiku is brevity and minimalism, so:
Thunder rolls –
a heaving dragon crawls
In fact, try this:
a heaving dragon crawls –
This inversion accomplishes two things.
First, we preserve the natural, chronological order – we see the "dragon" first, and then hear the thunder, right?
Second, and perhaps more importantly, this (hopefully) creates a moment of surprise, when the reader realizes the dragon is actually a bolt of lightning only after getting to the last line. This sort of word play is also a very typical haiku trait (though not mandatory in all haiku, of course).
I hope you find the above helpful. Do let me know if you have any questions or comments.
Oh, and I realize my revised version is far from perfect. It was just included here to illustrate my point. You are welcome to take it and improve it – it is, after all, your poem.
Once again, thank you for this image! I'm counting on seeing your August dragon in new incarnations soon, in many new poems.
Thank you very much for taking time to comment!
The ONE thing here is, I intended the clouds as the dragon - something big and thick and roiling, perhaps spitting lightning, but I did attempt to describe the clouds as the dragon. Hence the "gray," lol. Is there anything in punctuation/phrasing that you think would make this clearer?
And I apologize for the form - I will admit to going on the lessons in haikus I got in middle school. Obviously I need to do some more reading up on how flexible the form is.
Again, thank you so much for commenting!
My pleasure. And no need to apologize, really. According to many (including but not limited to my high school teacher), this would be a perfect haiku. I simply wanted to show you a different perspective. Which does not mean that this is any less poetic.
As for the cloud dragon – well, I must say I'm quite ashamed I didn't see it earlier. Maybe use "dark" instead of "gray" ("gray clouds" being a less obvious connection than "dark clouds", I believe).
A dark dragon
crawls toward sunset –