Category: Commentary

Monday was marked by frequent, short showers that totalled 1.1mm bringing the total for September to 26.2mm.

The interval between the showers produced some strong sunshine, totalling 3.9 hours, that raised the thermometer to a maximum of 16.9C. This was warmer than the previous day by 1.6C but still almost 2C below the September average.

Another cool night followed with the thermometer dropping to 8.9C, just below average, at dawn but recovering to 10.8C at 08.00.

This morning dawned with strong sunshine. The barometric pressure has been rising for the past twenty-four hours producing a ridge of high pressure, which should temporarily dampen the showers before the next depression arrives.

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.

Sunday:

Coolest day for three months (5th June) with a maximum of 15.3C being 3.4C below the 33-year average

Windiest day since 3rd August with a maximum gust of 27mph at 14.09

Wettest day since 20th August with 7.3mm of rainfall

Dullest day for a week with only 13 minutes of strong sunshine early sunday morning.

Lowest barometric pressure, with a reading of 990.0mb, since 5th June

After a bright start on sunday the cloud built up with frequent bands of rain crossing the area. There was a lull overnight until just after 3am when rain began to fall again with a heavier outbreak just before 7.15 am this morning.

This morning broke with heavy rain and the temperature having recovered to 11.6C at 08.00

Saturday brought us rapidly changing conditions as after a very sunny morning heavy showers arrived from three bands of rain producing 3.0mm of precipitation.

The total hours of strong sunshine amounted to almost 6 hours.

A maximum of 17.5C at 15.04 made yesterday the second coolest day this month being 1.2C below the 33-year average.

The wind was gusting during the heavy showers with a maximum gust of 25mph at 16.07, making it the windiest day this month and since 19th August.

With clearing skies the thermometer steadily fell overnight to a minimum of 5.8C, the coldest night since 20th May being 3.5C below the September average.

The below average day and night temperatures have meant that warmth has slowly radiated from the ground as at 08.00 this morning the soil temperature at a depth of 5cm gave a reading of 10.3C, the lowest since 11th May.

Fog briefly formed in the River Og and Kennet valleys but quickly evaporated as the early sunshine slowly lifted the temperature.

There was brief bright sunshine shortly after dawn but thick cloud quickly spread across from the west around 7.30 am.

The intermittent rain, heavy at times relented just after midday on friday, amounting to 3.6mm. This brings the total for September to 14.8mm with six successive wet days.

The welcome strong sunshine of 3.57 hours in the afternoon boosted the temperature to a maximum of 18.1C, which was 0.6C below the September average.

The UV levels this week have been at the lower end of ‘High’ but yesterday only reached into the ‘Moderate’ level.

The barometric pressure bottomed out just after midnight with a low reading of 996.2mb, the lowest reading since 29th June.

It was a very cool night with a minimum of 8.5C at 02.23 this morning, after which time the temperature rose a couple of degrees so that at 08.00 the thermometer was reading 10.8C.

Although breezy, with gusts to 20 mph late afternoon, thursday was a pleasant day with the maximum of 18.5C just off the average and up 0.4C on wednesday. There was much brightness and 0.83 hours of strong sunshine.

The cloud overnight menat a mild night with the thermometer not dropping below 13.7C, which was 4.3C above the average for September.

Light showers occurred around 3am and heavier bursts started just before 6am, amounting to 2.4mm.

The wind has been dropping out for the last five hours being light at dawn with heavy cloud and light drizzle in the air at 08.00.

The barometric pressure has been falling for the last 30 hours, now at its lowest since 28th June with a reading of 1001.1mb, heralding a more disturbed period.