Achieved:
* early morning ice skating session
* put washing out on line
* planted out sweet corn and "good mother stallard" beans which I'd germinated indoors
* gave them and everything around them All The Water
* replaced mulch
* straightened up, retained consciousness and balance as my head swam for gold, and came back inside for a banana and giant glass of water
* engaged smart home aircon system (muslin curtains hanging in front of open windows)

I think I'm winning. The only problem is, I do have to go to Bin Inn today, and I don't think it's going to get any cooler outside if I wait.....