What we would probably need is for a heatwave to firstly get established, and secondly last for at least a week in duration for us to have the best shot at it. IIRC, the all-time record in August 2003 was set a week or so after that heatwave first commenced.
That said, 37C was recorded at the start of July 2015 somewhere in the south and that didn't turn out to be a prolonged hot spell. My recollection is that the hot spell broke a few days into July and then it never really recovered for the rest of that month.
Originally Posted by: David M Porter