Category: Commentary

Monday 15th September
After a dry morning on Sunday the clouds built up with bands of showery rain arriving just before 14.00 that persisted into the evening. The sky then cleared with dry conditions overnight until just before 06.00 early Monday when a line of showers arrived from the southwest, travelling just to the north of Marlborough, with their southern edge producing brief, light rain here. The daily precipitation amounted to 8.6mm. That additional rainfall has taken the monthly total to 80.8mm or 110% of my 41-year average, making it the first above average monthly rainfall since February.

It was not surprising to find that the maximum of 17.2C was 1.8C below average due to the could and rain on Sunday, however, the peak occurred early in the evening as the cloud eased away and the sky briefly brightened. A minimum of 12.6C was logged at 06.04 early Monday, just before sunrise at 06.41 in Marlborough.

The start to Monday revealed a sky covered in clouds scudding across the sky although by 08.00 breaks were appearing in the cloud cover allowing weak sunshine to appear. The radar clearly showed the broken band of shower clouds drifting from the southwest, just to the north of Swindon then, with waiting in the wings a larger and more intense shower cluster, currently drifting closer to us across Somerset, that could arrive here mid-morning. It is a windy start to Monday with the wind forecast to increase this morning with a peak early afternoon. The depression is forecast to slowly drift across Scotland towards the North Sea as the day progresses that will result in the wind veering from south-southwest to west this afternoon.

A brief ridge of high pressure is likely to form behind the depression, although this will be just for Tuesday, before rain and strong winds return on Wednesday.

The past two days has seen a a tropical wave form off the Cape Verde Islands, where these usually originate, and moving slowly westwards north of the Bahamas, that today is forecast to have a 80% chance of forming a cyclone. The last one two weeks ago eventually fizzled out. This new development will be closely watched as the sea temperature just north of the Bahamas is currently 31C when a minimum of 26C is needed for a hurricane to form.

Westonbirt Arboretum. Today is the first autumnal image from a series of pictures I took at Westonbirt Arboretum some ten years ago. The colours deepen as the autumn progresses into October.

Sunday 14th September
Both the maximum of 17.6C on Saturday and the overnight very low minimum of 5.8C early Sunday were below average at -1.4C and -2.9C respectively. The past night was the second coolest this month. There were a couple of light showers during the past twenty-four hours that accumulated 1.2mm of precipitation.

Sunday arrived with a little brightness in the eastern sky although the sun was hazy thanks to thin high cloud. Just after 08.00 the cloud began to thicken ahead of the next weather front. The recent depression has been deepening whilst edging closer and will continue to throw showers or longer periods of rain this afternoon thanks to a warm front crossing the country after mid-day. As the weather front progresses across the country this afternoon the wind will pick up and be very strong for a period and will veer from the southeast this morning to southwest.

The rain radar at 07.00 showed precipitation arriving over Penzance whilst by 08.00 the fragmented band of rain had progressed eastwards over Devon with a more sustained rain band following behind. The forecast is for rain over central England shortly after midday.

The yellow weather warning put out by the Met Office yesterday for today will now extend over Monday for the strength of the wind, which will be very strong and could cause some damage and disruption to transport. However, the Met Office also state that it will not have sufficient impact to be labelled the first storm of the season.

Stourhead. This will be the last of the autumnal ages from Stourhead that has been described as “the most beautiful and magical of all the great landscape gardens. Tomorrow I will begin a new series of autumnal images, as the colours deepen, taken at Westonbirt Arboretum.

The showers on Friday were frequent and scattered that somehow missed our area for most of the day passing to the north and south, however a minor shower occurred just before 17.00 and another in the early hours that triggered the automatic rain gauge at 04.00, which produced a minimal amount of 0.8mm. The cloud was more persistent as the temperature rose resulting in cloud building up after around midday which was why the maximum of 18.3C was logged in the early afternoon at 13.06 being 0.7C below average. The minimum of 10.3C was recorded at 06.45 early Saturday just after sunrise in Marlborough at 06.38.

Saturday arrived with glimpses of weak sunshine between breaks in the cloud with minimal increase in temperature as the thermometer had only risen to 10.8C by 08.00.

The recent depression is still parked to the northwest of Scotland that will again today drive a multitude of showers circulating over the UK and limit the rise in temperature.

There is now much more confidence that the deep low-pressure system edging in from the Atlantic on Sunday will bring wet and very windy weather but not sufficient strength to make it the first named storm of the season. The Met Office yesterday issued a Yellow weather warning due to the forecast of severe winds in exposed areas. The Met Office spokesman said “Obviously we are in meteorological autumn now; it’s the sort of weather that we do expect at this time of year”.

The gardens at Stourhead were designed by Henry Hoare II and laid out between 1741 and 1780 in a classical 18th century design set around a large lake, achieved by damming a small stream.

Friday 12th September
The radar all day on Thursday showed a rash of showers crossing southern England that produced 9.6mm of precipitation in total. Once again the variable cloud cover limited sunshine so that the maximum early in the afternoon at 14.38, with a peak pf 17.3C, was 1.7C below average. Although the past night seemed chilly the minimum of 9.6C was 0.9C above average logged at 06.48, just a few minutes after sunrise in Marlborough at 06.36.

The mainly clear skies gave us a very sunny start to the new day on Friday that raised the temperature to 11.1C by 08.00. The recent complex depression is still lurking to the north of Scotland that will continue to throw showers across the country, already building over the west country heading our way. Between 06.15 and 07.30 they were passing on a southwesterly track just to the north of Marlborough and heavy over Swindon. When the temperature increases, as the sun gets to work in these unstable conditions, it heats the air that then becomes lighter and rises, as it gets higher it cools and the moisture condenses into rain showers.

The forecast track of the jet stream indicates that it will continue across the Atlantic, dipping to the south of the UK, rushing low-pressure systems towards us over the next few days.There is a strong possibility of a deep depression bringing heavy rain and strong winds on Sunday that has resulted in the Met Office issuing a yellow weather warning across southern England.

The new weather satellite MetOp-SG-A1 is just the beginning, according to a recent article. Five more satellites will follow over the coming decades, flying in pairs to provide continuous coverage. The mission is designed to deliver data that helps not just with day-to-day forecast, but also with longer-term climate models.

The Palladian villa of Stourhead House, built and modified by generations of the Hoare family, is the centre piece of the world famous landscape garden.

Thursday 11th September
Wednesday was an autumnal day with a strong southerly breeze gusting at one time to 23mph. The cloud built up late morning with a brief rain shower at 11.00 with showers or light rain on and off all afternoon with the heaviest fall logged at 18.30 when rain fell at the equivalent rate of 144mm/hour. As the cloud built up it limited sunshine, which is why the maximum was logged just after midday at 12.37 with a high of 17.7C being 1.3C below average, only the second below this month. The total rainfall for this month now stands at ……mm against my 41-year average of 66.9mm. The low of 10.7C was logged at 03.57 early Thursday being 3.0C above average thanks to the overnight cloud cover.

Thursday started with weak sunshine through brief gaps in the broken cloud that had raised the temperature to 12.2C by 08.00 with a brisk breeze coming from a southwesterly direction.

The complex low pressure system is anchored for a few days just off the north coast of Scotland that will continue to throw rain bands across the country in the form of scattered showers of varying intensity. It currently as a very low centre of pressure at 975mb this morning. In fact today there are four troughs of low-pressure forecast to cross the UK in a very disturbed period. A low-pressure trough is an elongated area of relatively low atmospheric pressure, often seen as a “dip” or “U-shape” on weather maps, which is characterised by rising air, leading to cloud formation, unsettled weather and potential precipitation like showers of steady rain.

The early data from the new MetOp-SG-A1 weather satellite looks promising, I read, but it’s not ready for public or operational use just yet. The weather satellite is still going through a long commissioning process to make sure everything is working exactly as it should. That includes testing, calibrating, and fine-tuning each instrument to ensure accuracy.