Cockpit's an oven on the ground (here). Canopy stays open until last possible moment. Once airborne, ram-air vents typical to gliders---always have full open. As Seahawk pointed out, temp declines predictably with altitude. With fresh air coming in cabin at a few thousand feet, cockpit's good... but there's no "cockpit cool" to soaring in Miami. In any case, mind's intensely on other things during flight. Land... canopy is opened immediately. Typical flight is 2 hours (for me.) Land. Rest. Hydrate. Then go again. Did 4 hour flight and was exhausted at end. Very foolish---mind was not clear towards end. Never again (in FL.) 3 hour is doable max during summer.
What's surprising is the speed at which air rises below a cumulus and into it. I look at clouds now and see lift.
Typical Florida day = towers form a few hours following sunrise. Those formations can last all day till a bit before sunset provided temp & humidity is right. If there's lots of moisture cooking off, cumulus goes nimbus in the afternoons... and dumps towards end of day. Just the right amount of moisture cooking off makes for a nice soaring day---lift opportunities widen and strengthen. Too much mositure makes for a short day---cloud cover spreads and wide area of sky dumps rain.
Have read about pilots being sucked up into cumulonnimbus even when they put glider into a vertical, nose-dive attitude. Some say their glider inverted without any sense of it doing so---they exited cloud inverted... then knew it. Also know of gliders being torn apart in CNs. I understand the lure. Potential price is rather steep.
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