“CHOP and change” weather characterised much of May. We barely escaped an overnight frost to start the month, with generally cloudy skies on May 1 resulting in a maximum temperature in Wellington of only 14.5C (58F). In contrast, the next night was a good ten degrees warmer, as rain approached on a south-west wind. This cleared quickly to give a sunny, breezy afternoon on May 2, and the next three days saw almost unbroken sunshine, but with ground frosts by night.

May 6 saw a transformation, as our first taste of continental warmth arrived from the south-east. Temperatures in Wellington peaked at 24C (75F) on May 8, the earliest date for that reading since 2011. Nights were also unseasonably mild, and the week May 6-12 boasted a mean temperature of almost 17C (63F), more appropriate for July. Trees seemed to burst into blossom and leaf almost overnight. It was, however, a cloudier period, with occasional light rain and a brief thundery shower on the evening of May 12.

With the wind then backing through east to north, and then north-west, the next few days were much brighter, temperatures dipping below normal once more. The strong sunshine made it pleasant enough out of the wind. It was all change again on May 17, the wind backing to south-west and bringing rain that continued into the night. Although less than 10mm (0.4in) was recorded in Wellington, it was to be the month’s heaviest fall. A little rain fell on each of the next five days, while the extensive cloud cover meant nights were rather warm.

The weather during the final ten days of May was largely influenced by high air pressure to the north of the British Isles. Winds were mostly light and variable in direction, and there were several days with prolonged sunshine. Clear skies resulted in a short sequence of chilly nights, a minimum of 3C (37F) overnight on May 25/26 being noteworthy but not that rare for so late in the year.

As the late Spring Bank Holiday weekend approached, our weather forecasters admitted to a great deal of uncertainty. Heavy rain was, however, expected in parts of the country. As things turned out, our area was blessed with perhaps the best of the weather on offer. Temperatures exceeded 21C (70F) daily from May 27-31, nights were very warm and even the thunderstorms missed us. These developed over Dorset on May 28 and drifted in a roughly north-westerly direction. We could hear the thunder as Taunton received a soaking but next day my rain gauge on the south side of Wellington yielded just 3.5mm (0.14in), even after further light rain during the night.

The final statistics for May 2016 are of interest. In spite of cool interludes, it was among the top ten warmest Mays on record in this region, the mean temperature of 13.4C (56.1F) being 1.5 degrees above average. It was also comparatively sunny, while the total rainfall of 39mm (1.5in) was less than 60% of the average. Overall, it has been a dry spring and it is six years since we had such a long spell with no heavy falls of rain.

Simon Ratsey

(WWN Weather Correspondent)