I'm not 100% sure where you stay, but I'll throw in my two cents, just for the hell of it. I live in a more desert climate (Southern California) and man is it pretty hot already, and at night it dips down to be about 45 degrees (cannabis supposedly slows growth tremendously after it dips below 60 degrees F. This is literally my first grow, ever and it's just outdoor. Since it's about 85-90 degrees during the daytime here, my young seedlings suffered burns from the really hot sun, but some faired better than others. I will drop some pics of my burned plants, I suppose. So, since they were getting burned from intense sun with no clouds, coupled with the heat, they're just not quite strong enough to handle it on their own, so I found an internet article that's saving me from this climate. I'll just paste the important outdoor part for ya :). Thanks, and best of luck to everyone's gardens :).
Internet post:
Seedlings intended for outdoor growing should be kept by a sunny window for the first week or two after emerging from the soil. When they have grown their second or third set of serrated leaves (after the the round cotyledons that initially emerge from the seed) seedlings are usually hardy enough to flourish in direct sunlight.
If outdoor temperatures are suitable, seedlings may be acclimatised to direct sunlight by giving them progressively longer daily exposure to outdoor conditions. Starting with about three hours outside, at the sunniest time of day, seedlings can be given an extra hour of outside exposure each day, so that within about two weeks they can be left outdoors permanently.