“It's the jet stream, you see,” earnest BBC weathermen and women explained to anxious news presenters welly-clad in water, “bringing with it wild winds, low pressure and precipitation.”
The reason was actually more simple than that. “Rain, rain go away...” a mother had taught her child the rhyme some months ago. Rain, charmed by the child's lisping entreaty, obeyed and there followed a summer of brilliant sunshine and high temperatures.
Unfortunately, the child had picked up the rhyme wrongly. “Come again EVERY day!” she trilled. Rain could not but obey.