A major driver is that climate is changing as a result of the well-documented way humanity is burning fossil fuels. Temperatures are only rising.
Paragraph 2 of the Fifth story down on the BBC News front page at this precise moment. Lawks.
The Weather section is, unsurprisingly, concerned mainly with weather rather than climate. However:
Are we in for a summer of serial heatwaves?
Human-induced climate change is shifting the baseline temperature higher and this is making our heatwaves hotter, more frequent and longer lasting.
How hot a 1976-style heatwave would be today
In the 50 years since the record-breaking heatwave of 1976, scientists say that the influence of human-induced climate change means that should similar weather patterns occur again we could expect our weather to be much hotter.