Another dry day

With less sunshine on Saturday (6.6 hours) it is not surprising to find that it was less warm than Friday with a maximum of 22.6C, still 1.7C above average.

The past night was also above average (+1.7C) with a minimum of 13.2C due to cloud cover.

Sunday arrived with brief, hazy sunshine. The barometric pressure has been slowly falling for the past two days as another Atlantic depression approaches the country.

Update on Sunday at 16.50: very warm Atlantic air with high humidity (over 60%)and a maximum of 25.4C at 15.10, made it rather uncomfortable this afternoon.

July 2019 summary

July was a month of two halves. During the first 16 days of the month we had just 0.3mm of rainfall, which fell on the 6th with the remaining 15 days totally dry.

However, with the wind then backing predominantly into the southwest the rains arrived, especially on three particular days. The daily rainfall on the 19th, 23rd and 30th was 12.9mm, 12.2 mm and 15.3mm respectively. These three days accounted for 67% of the monthly total, which at 50.8mm was 9.1mm below the 35-year average.

The rainfall extremes for July reveal that in 1999 just 10.1mm of rainfall was recorded and the year 2007 was very wet with no less than 127.2mm, which was more than twice the average.

Taking a broader look at the rainfall statistics I find that the rainfall for the period January to July was 402mm whereas the 35-year average for these seven months is 450mm, a difference of 48mm.

It was not surprising to find that evaporation from ground sources and plant life was very high during the month. We lost the equivalent rainfall of 108.1mm with eleven daily totals exceeding 4mm, the peak being 5.04mm on the 23rd.

Looking at the temperature statistics I find that the mean temperature was 1.2C above average. It is interesting to note that the mean was 3C below the very hot July in 2018.

There were 19 days when the maximum temperature rose above the 35-year average with several days notable for very hot weather. At the end of the month there were five days with exceptional heat from the 22nd to the 26th with 25.6C, 32.0C, 29.0C, 32.6C and 25.2C respectively.

At the beginning of the month there was also a short hot spell with daily maximum exceeding 25C. At that period the soil at a depth of 5cm, when read at 08.00, was at its warmest with a reading of 22.9C. With an average monthly temperature at that time of day of 19.2C, this was 2C down on the hot, dry month in 2018.

There were 276 hours of sunshine during the month with the sunniest occurring on the 4th with 13.77 hours.

Fog occurred in the early hours of the 23rd and 29th that reduced visibility to 100m but quickly dispersed as the sun got to work.

The UV level on 24 days rose up to the ‘very high’ category with on the cloudy, wet day of the 19th only ‘moderate’.