From North Yorkshire weather from the BBC -

"May was warmer, drier and sunnier than normal this year...

Sunny May

Fortunately there were no hurricanes in May, indeed it may surprise you that the month was actually warmer, drier and sunnier than normal.

How could we have a month without breaking a record! In fact this month's accolade goes to Fylingdales, high up on the North York moors, which recorded its highest ever May temperature - 27.8C (82F) on Saturday 31st May.

Temperature 16.8 deg C (average 15.7 deg C)
Rainfall 43mm (Average 56mm)
Sunshine 197hrs (Average 185hrs) "

So that would be about 6 hours a day to take the picture.

How was it done? Well...

We have some swifts nesting just above our bedroom window and have got to know them quite well. It was an easy job to teach them to use the digital camera (one holds it round his neck, one points it, and one pushes the shoot button) and they seemed to reckon it is a reasonable trade for a summer's accommodation.