Category: Commentary

After a mild and dry start on Wednesday the rain arrived mid-morning for several hours and again between 7 and 8pm.

The rainfall amount ver the past twenty-four hours was 10.6mm and in the brief storm around 3pm contained small hail. The rainfall total for December now stands at 47.2mm, which is 53% of the long-term average.

The temperature yesterday and overnight yo-yoed up and down as the rain bands came and went with clear skies in between. The highest temperature was 2.1C late afternoon, just below the reading at 08.00 this morning. The maximum temperature was late morning with a reading of 8.1C, just above average.

In the gusts the wind was very strong from the west with a maximum of 33mph.

After a very hard frost Monday night / Tuesday morning the wind backed into the south lifting the temperature to around 5C during daylight hours. It took until late morning before the thermometer struggled above freezing and reaching its maximum.

We enjoyed 4.28 hours of sunshine, much of it hazy due to thin high cloud.

Late evening another weather front arrived from the west bring thickening cloud and light rain. The thermometer reached a maximum of 7.5C at 01.21 this morning before falling back to 5.9C at 08.00.

The rainfall last night, and again after the next weather front began to cross the area this morning, produced 3.9mm of precipitation.

This morning is dull and wet as the rain increases with all traces of the recent snow having disappeared.

Monday continued where Sunday left off with rain and sleet until mid-morning producing 1.3mm of precipitation.

The thermometer struggled to reach 1.2C at 13.31 making it the coldest day since 26th January and a significant 6.6C below the 33-year average.

The thermometer fell away late afternoon and dropped to freezing at 16.59, falling away to -1.3C by 19.20 and then hovered around that temperature until just after midnight when it dropped steadily to a minimum of -5.1C at 06.25 this morning. There was then a slight recovery to -4.3C at 08.00. This makes it the coldest night since 21st January.

As the deep depression over the near content drifted away the barometric pressure began to rise steadily then rapidly producing a rise of 28mb in the 24-hour period.

The UV level was non-existent for the second day and the soil temperature at a depth of 5cm was 0.2C at 08.00 this morning.

With a totally clear sky this morning there is promise of sunshine when the sun makes it late appearance above the horizon at this time of year.

The snowfall decreased during the morning, turning to sleet. More sleet, but predominantly rain fell in the early hours of Monday morning producing 9.2mm of precipitation, which brings the total for December to 31.4mm. The snow was wet in nature, sticking to any surface on which it fell. To obtain the rainfall figure I carefully scooped out the snow from the rain gauge and slowly melted it to add to the rain that had fallen earlier.

Although the maximum recorded was 3.2C, this resulted from a short pulse of slightly warmer air around 10.20 on Sunday that lasted for just over half an hour when by 11.00 the thermometer dropped back to 0.8C and stayed there for most of the day.

The overnight thick cloud was intensified, as was the precipitation, from the effects of another deep low pressure system, this time centred over the continent.

The temperature at 08.00 was 1.1C with strong northeasterly winds gusting to 32mph at 06.53 and moderate rain and some sleet.

A notable feature, meteorologically, was the extreme fall in barometric pressure as the intense low-pressure system crossed this area dropping 33mb in 24 hours, from 1019mb on Saturday to 981mb on Sunday morning. Technically called Cyclogenisis when the barometric pressure fall is in excess of 24mb in 24 hours.

With a maximum of just 2.9C at 13.33 on Saturday it was the coldest day since 11th February being 4.3C below the 33-year December average.

There was no precipitation until just after 02.15 this morning, when initially rain began to fall that readily turned to wet snow after 04.30 as the moist air ran up against the cold air from previous days. The total precipitation from rain and snow was 14.6mm, making it the wettest day since 2nd August and bringing the total for December to 22.0mm.

Having hovered around 1C for most of the day there was a rise in temperature from midnight until just after 2am when it reached 2C then fell to a minimum of 0.6C.

The barometric pressure at 08.00 this morning was 975.3mb, the lowest reading since 20th November 2016, as the centre of the low pressure passed over this region.