When the rain starts to fall, it comes down with increased intensity on soils that are not best able to soak up high levels of water.
“As well as increased rainfall extremes, we are seeing hotter summer which can bake the soil and reduce its ability to absorb water,” said Prof Mark Smith, from the University of Leeds.
“In turn this amplifies the more direct effects of increased rainfall intensities as more of that water makes it into the rivers.”
There is also some debate among scientists about whether a warmer world makes these storms slower moving, which would exacerbate the amount of rainfall they deliver.
This year we have seen some evidence of this type of storm and the devastation that it can bring.
In September, Storm Boris brought death and destruction to several countries across Central Europe, again made stronger by the high heat in the Mediterranean.
This slow-moving disaster was said by scientists to have been made twice as likely by climate change.
In Spain, the lack of precise warnings has led to criticism that more could have been done.