Hi, Sue,
I've looked at this a few times and must admit to a few misgivings. Blank verse to me always speaks of Milton's epics -i.e. it is the modern equivalent of the Classical period's Dactylic Hexameter. I'm not sure it works in short forms like the sonnet. That said, let's look at your poem.
QUOTE
A Summer in Cincinnati Is...
Where, earlier than the solstice every year,
the summer is announcing its arrival;
I have a couple of nits with this part; Summer appears in the title and then almost immediately in the body of the poem - perhaps use the longer 'Summertime' in either/or position? Then the sense of lines 1/2 threw a bit in that summer always arrives before the solstice, which marks mid-summer. Is there a way to suggest a 'bringing forward' of the solstice because Summers start earlier and last longer - though that would fail on logic since eventually it would be the only season.
QUOTE
where heavy handed heat will sap your soul
and leave it draped across the sweat-soaked sheets;
where thick, dank darkness drains into your dreams
to stifle all desire and hamper sleep.
where morning, dripping in a moldy mist,
negates all hope the spell’s inclined to lift;
All these 'where' starts in a relatively short piece are distracting and seem 'lazy' if you'll pardon the expression. If you had used 'with heavy handed heat that saps your soul' and 'when morning...' it would have broken the dominance of 'where' (verb endings would have to be amended to agree of course). Might have gone with 'dispels all hope' and use 'curse' instead of 'spell'.
QUOTE
where steamy midday shuttles in its sour
white-hazed air to steal your breath and leave
you lazy, limp and listless. By twilight
you’re longing for one brief cool breeze to brush
across your naked body like a leaf;
where sometimes sudden storms bring sweet relief.
I like this last section and note that you use a rhyming couplet finish - perhaps that's why
The overall layout of this sonnet is more akin to an FV offering, which may have been your intention, but I found it distracting - given the sonnet description.
I'm sorry I couldn't be more welcoming with this, Sue, perhaps if you'd used 'Cincinnatti is..' as your intro and described all four seasons it might work better. But remember these are just my opinions, yours to use or lose as you choose, it is your poem and the 'lazy feel' might have been deliberate to reflect the effects described,
Jim