After more than 250 appearances of this regular column, one might be forgiven for thinking that there is nothing new to report on our local weather and climate. But we’ve seen that the improbable is becoming increasingly likely, and extremes more common. April 2021 was the frostiest on record, May the wettest, September saw unprecedented heat and it hardly rained in November.

After all that, the first part of December was unexceptional. No day was completely dry but there was some sunshine on six of the first seven days. Temperatures were appropriate for the season with a touch of frost on a couple of nights. There were gales in the night of December 6, as storm ’Barra’ crossed the British Isles, a short spell of very intense rain during the afternoon of December 7 marking the passage of a cold front. Some 13mm (0.5 inch) deposited in the Wellington rain gauge was the most for almost six weeks.

Although December 8 was rather unpleasant with squally winds and showers, the maximum temperature of 7C (45F) in Wellington was close to normal. December 10 was quite sunny and - at last - rain-free, with rising air pressure over the continent. This led to a week of unseasonably mild, dry weather. Such wind as there was came initially from the south-west but veered to south-east by December 17, by which time the anticyclone was centred over South-East England. It was also a very dull period, but the blanket of cloud kept the nights warm, a minimum of 11C (52F) in Wellington on the night of December 15 being ’noteworthy’ .

By December 19 the air over us had cooled somewhat, a light easterly breeze keeping the day’s maximum temperature in Wellington down at only 5.5C (42F). A few hours with clear skies during the night of December 21 led to our lowest temperature of the month - minus 1C. However, already by next morning mild air was returning, the clouds parting to reveal the noon-day sun for the first time in ten days. This marked the start of an unsettled spell with some rain every day and temperatures well above the seasonal norm.

There was patchy light rain all day on Christmas Eve, while Christmas Day began with bursts of heavy rain. After a lull, it set in again to give a very wet afternoon and night, giving a ’daily’ total of 21mm (0.84 inch). Early risers on Boxing Day were greeted by fog but this lifted by mid-morning to give a day with enough sunshine to encourage people out for a breath of fresh air. Exceptionally mild air was forecast to be on its way from the sub-tropics, and so it proved. The last four days of the year were about as warm as physically possible, peaking with our December record temperature of 14.7C (58.5F) on New Year’s Eve.

Despite the wet end, the month’s rainfall of 95mm (3.75 inches) was 20 per cent below average. It was a notably dull month but with a mean temperature of 7.8C (46F) - almost 3C above average - it was the equal second warmest December on record. And after the coldest spring for a generation, 2021 was overall much warmer than average, thanks to the second half which was by some margin the warmest ever.

Simon Ratsey

WWN weather correspondent