SWMBO commented that the water coming out of the cold (direct mains) tap was warmer than usual. And I tend to agree.
Without arsing around with thermometers and all that malarkey I wonder how the recent heat may have raised temperature of water underground. If at all.
I am aware that the fact the pipes must run in open air in the house (Mondays temperature 29C) may have some effect.
However a very unscientific messing around with Chatbots suggests that the 1,5C above SNT that I logged for all of June may equate to
Extra continuous radiative input: ~ 6.8 W/m²
Total extra energy in June 2025: ~ 17.6 MJ per square metre
This estimate assumes black-body emission into clear sky—it doesn’t account for clouds, humidity, or circulation, but gives a solid first- order approximation of the energy difference tied to a 1.5 °C anomaly.
Let me know if you'd like the same calculation applied to July or using humidity corrections!