Why not wait till summer when it is not so cool? 
Ken
For the honest truth, it's actually supposed to hit 92F. today, and that's on the downward slide towards civilized. I'm not going to do the concrete mixing until it cools off, probably September, but before the monsoon season starts.
The question I fforgot (double ff's for Howard and Gerald), is what do you do to slow down the setting of the concrete? I know about ice, but don't know if it needs to be crushed or iff cubes are ok. I read something about "the mix" on a ffishing fforum, but I don't know what that reffers to. Less lime or something? Is there an additive that results in a slower set?
I'm not all that concerned with the concrete sticking to the forms, but I'll be sawing them up at some point, to put them in either the emergency firewood stash or in the yard waste recycling bin. Less concrete presidue (sic) will be easier on the saw blade. The next DIY project is a shed, but I'm not going to make a slab foundation for that...pier blocks and PT lumber. This will NOT be a "tiny home" for an "urban sportsman" to occupy.
In one of my first posts on this topic, I believe I mentioned using the wheelbarrow to transport sacks (60 lbs each) around the house and up the ramp to the upper backyard. Started with 3 bags and couldn't get them up the ramp, so backed 'er down to two bags at a time. A couple of times in the distant past, I have been a wheelbarrow driver for a friend, transporting wet concrete from the concrete truck to the back corner of his yard, pouring the foundation for his new garage, IIRC. It sucked!!! I can't recall why we couldn't back the truck in there. Probably one of those deals where the mind blocks out bad memories, like near-fatal accidents, shark attacks, etc.

Steve