Category: News

Yesterday the thermometer rose a little higher than the previous day to a maximum of 4.7C just after midday, even so this is 2C below the mean for January due to the wind backing into the west, a slightly warmer air flow than from the north. The thermometer fell slowly to around 2C late afternoon with a minimum of 1.7C just after midnight. The increased cloud cover this morning meant that the temperature has recovered to 4.6C at 08.00. No rain has fallen in the past twenty-four hours that also brought almost 2 hours of strong sunshine, down from the 6 hours of the previous day.

The thermometer dropped to -4.2C at 02.56 the morning but has since recovered to -1.8C at 08.00 after a cold day yesterday with a maximum of 3.4C, but there were 5.9 hours of strong sunshine, the most for a month.

N.B. I apologise that the Daily Statistics page will not be available for a few days as the website has been in the process of being re-designed. Various other pages are being updated.

December 2016
In 1862, George Elliot, the novelist wrote: “The constantly heavy-clouded and often wet weather tends to increase the depression. I am inwardly irritable and unvisited by good thoughts”.

There were so many days in December when this description applied as the very thick, low cloud and days with fog occurred all too frequently. There were sixteen days when no UV light was measurable and thick fog, with visibility down to 100 metres, on four days.

December was mild and very dry, which climatologically is a relatively rare combination because typically mild Decembers are wet and cold Decembers are dry.

Although there were thirteen days with measurable precipitation the rainfall for the month amounted to just 22.6mm. The wettest day was the 10th when 8.5mm fell, over a third of the total for the month. This makes December 2016 the third driest December I have recorded since the station was started in 1984 and the driest month of 2016. It is no wonder that the Rivers Kennet and Og are running so low.

The 32-year average was 91.5mm, making a deficit of 68.9mm. The two previous very dry Decembers were in 1991 and 1988 with 21.8mm and 17.6mm, respectively. The record rainfall for December occurred in 2013 when 157mm was logged.

It is not surprising that the Rivers Kennet and Og are running so low as although November rainfall was above average the October total was very low. The rainfall for the whole of 2016 was 767 mm, which is 91% of the 32-year average or 72mm below.

Although there were eleven days when an air frost occurred, it was a mild month with the mean 0.7C above the long-term average. There were a couple of colder spells at the beginning and end of the month but twenty-one days when the maximum exceed the mean for December. The warmest day occurred on the 9th when the thermometer rose to 13.7C, which was 6C above the mean. The coldest night was measured on the 1st of the month when a minimum of -7.1C was recorded followed by -6.3C on the 2nd.

The peak barometric pressure occurred on the 27th with a reading of 1044.9mb and any wall barometer at home, accurately set, would have shown the arm far around to the right at the ‘Very dry’ setting. In fact it was the highest December barometric pressure I have recorded since 1991.

Many days were very calm as the intense high pressure dominated for much of the month. This resulted in many days with stagnant air and some days with hardly a movement of the air for extended periods. For example, on the 27th the anemometer measured a peak of just 5mph for the whole day with two very similar days when a maximum was 6mph, which cannot be classed as a gust of wind, just a brief movement of air. In contrast to this calm scene was a very breezy day that occurred on the 23rd when a maximum gust of 41mph was recorded.

To look on the bright side there fifteen days with strong sunshine, the sunniest occurring on the 29th with 5.77 hours.

The very dry Decembers of 1988 and 1991, as mentioned above, were followed by very dry Januaries with between a half and a third of the mean monthly rainfall. However, January 1989 was mild and January 1992 cold, so no consistent trend there. What will January 2017 bring?

The ‘Cold’ weather front arrived just before midday yesterday bringing a dramatic change to the weather. The light rain that started an hour before became heavier, the wind abruptly veered from the south into the north just after midday, gusting to 23mph, and the temperature dropped from a high of 7.9C to 2.2C with a wind chill factor equivalent to -1C.  All this occurred as the barometric pressure, that had been falling for two days, abruptly starting climbing again. The rainfall for the past twenty-four hours amounted to 5.4mm.
Overnight, as the cloud cover cleared, the thermometer dropped to 0C with a ground frost. This morning is dawning clear with the sun seen to be rising above the horizon as I write this item. The gloom and thick cloud of the past few days has disappeared, thankfully, with very clear visibility.

N.B. I apologise that the Daily Statistics page will not be available for a few days as the website has been in the process of being re-designed. Various other pages are being updated.

Yesterday was another in the succession of gloomy days with low cloud over the Marlborough Downs and misty conditions. There was a light shower mid-morning and another in the early hours of today. The maximum was 7.8C, close to the mean for December but due to the cloud cover overnight the minimum was 4.6C, which had risen to 6.8C at the time of readings at 08.00. However, with the barometer falling to its lowest reading for December of 1015.2mb at 08.00 today, the weather is about to change. There were indications yesterday as there was more movement of air with a maximum gust of 16mph, the strongest for almost a week.
The total rainfall for December was 22.6mm, which is just 25% of the long-term mean, or 69mm below. In between the cloudy days we did enjoy 38 hours of strong sunshine.
A more detailed analysis for December and the year of 2016 will follow tomorrow.

Latest at 16.00 on Sunday 1st
The ‘Cold’ weather front arrived just before midday bringing a dramatic change to the weather. The light rain that started an hour before became heavier, the wind abruptly veered from the south into the north, gusting to 23mph and the temperature dropped from a high of 8C to 2C with a wind chill factor equivalent to -1C.

With a maximum of 8.1C yesterday, just above the mean, and 2.2 hours of strong sunshine it was a much better day. Again there was no rain, the fifth consecutive dry day with the monthly total still standing at 21.6mm, which is 70mm below the 32-year mean. The lack of rain this month and also in October can be seen in the very low state of the Rivers Kennet and Og running through Marlborough.
Low cloud, giving misty conditions, has returned overnight. The stagnant air trapped under the intense high pressure will take time to lift and clear as the is air very still. There was a high of 9mph yesterday in mid-afternoon but over the past twenty-four hour there has been very little movement.