AFTER the exceptionally sunny end to May, June began on a disappointingly dull note that established the overall theme for the month.

With no sunshine, and a light breeze from the north-east, June 1 was the coolest day for several weeks, the maximum in Wellington barely reaching 16C (61F). Things improved over the next few days, with good sunny spells and temperatures lifting to normal and then above.

Much as occurred in early May, very warm air drifted over us from France, and it became increasingly thundery. Temperatures peaked at 25C (77F) in Wellington on June 6, in a week that boasted a diurnal mean temperature of almost 18C (64F), four degrees above normal.

June 10 marked the start of a disappointing fortnight that would contain not a single really sunny day. A slow-moving, fairly shallow area of low pressure centred over England introduced very muggy air to our region, with many other parts of the country enduring violent thunderstorms and locally severe flooding. Rainfall amounts in Wellington were small. Temperatures by day were about average, boosted by spells of sunshine between the showers, but nights continued to be consistently on the warm side.

June 15 saw the first heavy rain of the month, 10mm (0.4in) arriving with thunder and lightning in the middle part of the day. The following day, very dark clouds and thunder over the Blackdown Hills threatened a repeat performance, but this time Wellington was spared.

As we approached the Summer Solstice, any hopes for appropriate weather were dashed by an active weather system to the north of the British Isles once more drawing warm, moist air up from France.

A drizzly morning on June 18 gave way to a bright, fresh, sunny afternoon, while the next day was thoroughly dull with rain setting in during the evening. The resultant 12mm was our heaviest fall since March. We then had four days with very humid, damp conditions. Any sunshine was at best hazy but temperatures were above average, especially at night.

At last, on June 24, we awoke to find that the oppressive continental air had been swept away by the west wind. We enjoyed our sunniest day for three weeks, typically English in that it also featured a brief but intense shower after lunch. That set the scene for the month to close with the kind of summer weather that Britain has always done best: no two days the same – spells of light rain, some strong winds, limited amounts of sunshine and a little token warmth on June 30.

The statistical summary for June contains some paradoxes. It was unusually cloudy, and with 14 days with measurable rainfall, it’s a surprise to find that Wellington’s total of 49mm (1.9in) was 20% below average. The past three months constitute the driest such period for five years.

Perhaps less believably for the casual observer, June was unusually warm. The mean temperature of 16.1C in Wellington was more than a degree above the 1981-2010 average, mainly thanks to the unprecedented frequency of very mild nights. Provisional figures suggest it’s among the five warmest Junes in our region since the record-breaking summer of 1976, although very much what we’ve come to expect in the 21st century.

Simon Ratsey

WWN Weather Correspondent