Category: Commentary

Saturday produced another 4.4 hours of strong sunshine with the UV level at the ‘Mpderate’ level as it has been for the past week or so.

The temperature eased up a little on Friday’s maximum with a peak of 15.9C, still 2.8C below the September average.

It was almost a dry day, which would have been the first in the last ten days, but a shower late evening produced 0.3mm.

With clearing skies again the thermometer dropped steadily to a minimum of 5.5C, almost identical to the previous two nights, which was 4C below the 33-year average.

The temperature eased upwards after 5am as drifting fog dropped down limiting visibility to a maximum of 300m.

Friday produced a couple of showers midday and then early evening amounting to 1.9mm being the ninth consecutive day with measurable rainfall.

The wind having veered into the northwest pegged back the temperature, that combined with reduced sunshine of 4.31 hours meant a cooler day again, 2C down on thursday. The thermometer peaked at 13.51 with a maximum of just 14.3C, which was 4.4C below the 33-year average. This was the coolest day since 9th May

With predominantly clear skies the temperature dropped consistency overnight producing a minimum of 5.4C, some 4C below the September average. As a result of the moisture and very low temperatures radiation fog formed again in the River Og valley.

There was intermittent sun after dawn that by 07.45 had dispersed the fogged slowly beginning to raise the temperature so that at 08.00 the thermometer read 6.7C, the coolest morning since 29th April.

Thursday was again plagued by showers throughout the day, amounting to 2.8mm, bringing the September total to 41.8mm being the eighth successive wet day.

The greater amount of cloud combined with the west to north-west wind gusting to 23mph, pegged back the temperature to a maximum of 16.1C, which was 2.6C below the September average.

The main feature of the last twenty-four hours was the very low overnight temperature as the thermometer dropped to 5.3C. This was the coolest night since 20th May and underlines that autumn is truly her, being 4C below the September average.

This morning broke with intermittent hazy sunshine through broken cloud that slowly dispersed the fog that had formed before dawn in the River Og and Kennet valleys.

We enjoyed 7.9 hours of strong sunshine on Wednesday with no rainfall during the daytime. Despite the sunshine the westerly breeze moderated the temperature with a maximum of 16.4C, down a degree on Tuesday and 2C below the average.

However, a narrow band of rain arrived at 20.25 with a much heavier pulse at 22.20 resulting in 7.1mm of rainfall. This brings the total for September to 39.0mm.

It was a cool night with the thermometer dropping to 7.2C at 6am resulting in the coolest morning this month at 08.00 with the temperature at 8.4C.

The image of a red sky at dawn indicates that more rain is likely during today, although there has been intermittent sunshine for the first few hours of Thursday.

Tuesday brought us a twenty-four hour period in two distinct halves.

We enjoyed 7.28 hours of strong sunshine during the day that with relatively modest breezes gave us a maximum of 17.3C, slightly up on the previous day but 1.4C below the September average due to the westerly air flow.

The wind backed into the south just after 4pm and after a quiet period, began to rise with strong gusts after 8pm. This evening period was marked by several hours of rain amounting to 5.7mm, the third wettest day this month, that ceased just before midnight.

Just after 1.30am the wind began to increase significantly with frequent gusts above 30mph and a peak gust of 39mph at 02.01.

The cloudy, windy night meant a mild night with a minimum of 10.2C, almost 1C above the 33-year September average.

This morning we have enjoyed bright sunshine since dawn but by 08.00 variable cloud had drifted in on the breeze that had veered back into the west. The humidity at 08.00, of 84%, was the lowest this month.

Summer 2017 summary

Both temperature and rainfall were above average, as was sunshine.

The total rainfall amounted to 192mm, which was 10mm above the 33-year average. It is interesting to see from analysis that the trend for summer rainfall is upward. In the period of the early 1990’s to 2005, the average was around 165mm but the upward trend shows that the average over the last ten years is closer to 182mm per summer.

There were three very wet days with heavy rainfall that produced 23.6mm on June 5th followed by 26.2mm and 23.5mm on July 11th and 21st respectively.

During the three months there were 40 rain days when greater than 0.1mm was recorded in a day and 29 wet days when rainfall equal to or greater than 1mm per day was recorded. The data for both features has a rising trend. For rain days an increase from around 35 to 43 days each summer with wet days showing an increase from around 26 to 31 occurrences each summer.

It was the 8th warmest summer since my records began in 1984 being 0.6C above the 33-year average. This was principally due to a very warm June, which was 2C above the average also the warmest June since records began in 1984. July was just above average although a sad August was 0.5C below average.

There were several very warm days. June gave us four days with above 30C maxima producing 32.2C on the 21st. July started warm with a peak maximum of 30.4C on the 6th, however August could only manage a maximum of 28.2C on the 28th.

In total there were 389 hours of strong sunshine, which was 75 more than that received in 2016.