Category: Commentary

With no rainfall on Monday we did not feel the full effect of Storm Debi although it was a very breezy day with the wind often gusting over 20mph and a peak gust of 32mph. The storms that occurred were to the north with an intense one over the Swindon area early evening, I know because I drove through it, just missing Marlborough again.

After a very warm start to the day at 14.1C the temperature slowly fell a few degrees, but a very mild night followed with an overnight low of 9.5C being 5.6C above the 39-year average.

Tuesday dawned with thin but total cloud cover. There are four low pressure systems circling the UK so we can expect another unsettled day with the possibility of more showers although mild again thanks to the southwesterly breeze, that will shortly veer into the west, however, much less strong than on Monday.

Incidentally, Storm Debi occurred at the earliest point in a storm season that the letter D has been reached in the alphabet. The storm season in the UK starts on 1st September each year.

Sunday was best forgotten as regards weather as it was a dull and damp day with more rain overnight. Another 13.8mm of precipitation was recorded that took the monthly total to 89.0mm, just 1.9mm short of the 39-year average for the whole of November.

The thermometer slowly rose to around 10C by mid afternoon and stayed thereabouts until around midnight when the wind changed into a southerly as storm Debi approached. At the same time the change in direction to south, a much warmer direction, saw the thermometer slowly climb during the early hours of Monday to 14.0C at 08.00.

The temperature of 14C at 08.00 on Monday was 3.8C above the average maximum and 10C above the average minimum. The remnants of cloud from the associated overnight weather front gave signs of breaking with brightness beginning to appear. However the wind strength had been rising since midnight with a maximum gust of 25mph, but forecast to rise further during the morning as Storm Debi closes in.

The meteorological ‘col’ of yesterday brought the expected calm conditions with minimal air movement and modest sunshine that lifted the temperature to 10.7C, just above average. The temperature fell steadily away as the evening wore on to reach a low of 2.7C, being 1.2C below the average minimum, at 21.35. Subsequently advancing cloud from the next weather system meant that the thermometer did an about turn and rose to 3.4C at 23.00 then 4.5C by 08.00 Sunday. There was minimal rainfall overnight of 0.7mm.

Sunday revealed misty condition with low cloud and moisture in the air but not quite drizzle. This was due to another depression advancing from the Atlantic. Initially, the light breeze came from the south east but will veer into the south then southwest after midday as the depression moves towards the UK. This will mean mild unsettled weather will return with minima around average compared to the last two very cool nights that brought a touch of ground frost on Saturday.

The rain gave way to sunshine at 10.15 on Friday after adding another 2.5mm of rainfall. However, the light breeze veered into the north late morning, which is a cooler direction, so it was not surprising to find that it was the coolest day this month. The thermometer rose to only 9.1C at 12.32, which was 1.1C below the average and the coolest day since 14th April (8.7C).

The thermometer fell steadily away during the evening to around 3C but during the early hours under a clear sky fell to 1.5C producing a temporary ground frost, its lowest at 07.14 Saturday, which was 2.4C below the average.

Saturday revealed misty conditions with radiation fog forming briefly in the River Ogg valley that had all but cleared by 08.00. The temperature had begin to rise as the sun rose reaching 2.1C by 08.00.

We are currently experiencing a metrological col. That is, the UK is between two opposing high pressure systems, north and south, and two low pressure systems, west and east. A col brings calm conditions.

The cool westerly breeze, gusting to 21mph on Thursday, meant an average maximum of 10.3C even though there was sunshine in the morning and early afternoon. However, another weather front saw cloud building after 14.00 that meant more rain later in the day and overnight amounting to 13.2mm. That took the monthly total to 72.0mm, just 19mm short of the 39-year average and only a third of the month to date. The minimum of 5.9C was 2.0C above he average.

Friday barely dawned as it was so dark due to the extensive weather front and associated low cloud that covered our area with rain continuing to fall. The wind will change in direction starting as a light air movement from the northeast to north and then a westerly quadrant as the day progress due to the depression moving eastwards across central parts of the UK to the North Sea.