New record for hottest day!

The southerly air stream that brought the very hot air from North Africa and Spain, called a ‘Spanish Plume’, arrived with a vengeance on Monday. After a warm start the thermometer steadily rose, with a slight pause between 15.15 and about 15.30 due to variable cloud, to reach a maximum of 35.8C at 16.47. This peak was 13.1C above the 38-year average and broke the record for the hottest day I had recorded since this station opened in 1984, previously held with a peak of 34.8C on 19th jury 2006.

The air was very dry again with the humidity falling to just 28% at 16.10.

There was no let up overnight as the temperature did not drop below 17.9C, which was 6C above the average.

After strong sunshine at the start of Tuesday thin, light cloud began to slightly mute the strength of the the sun.

Set against the miserly rainfall of 4.3mm on the only day that rain fell this month, we are now losing the equivalent rainfall of over 5mm daily through evaporation from ground sources and plant life. The total loss through evaporation, due to the lack of rain, intense heat and brisk drying winds, now stands at 66mm for July so far.

Because of the lack of rain and high evaporation the humidity has been very low for the past few days. At this time of year the humidity at 08.00 is often from 80% to 90+%. Yesterday at 08.00 the humidity was 59% and lower again this morning at 08.00 read 56%.

Tuesday Monday
Temperature at 08.00: 24.5C. 22.2C
09.00: 29.1C. 25.6C
10.00: 32.8C. 29.9C
11.00: 33.6C. 31.7C
12.00: 34.2C. 32.2C
13.00: 35.2C. 34.2C
14.00: 36.3C. 34.1C. The current 36.3C exceeded yesterday’s record high
14.20: 36.7C. a new record!
15.00: 35.3C. 34.6C
16.00: 34.3C. 34.2C – cloud began to encroach after 14.40
17.00: 30.7C. 35.6C – weather front passing over – no rain