The sunshine was intense on Saturday pushing the thermometer mid-afternoon to a maximum of 28.7C being a significant 8.1C above average. Light variable cloud limited any further rise but this was the hottest day since the 21st when 29.7C was logged. The past night was slightly cooler than the previous but a minimum of 17.1C was still 6.9C above average.
The start to Sunday revealed a mainly cloudy sky although there were brief brighter intervals in the minimal cloud breaks before 08.30. The thermometer had risen to 20.0C by 08.00.
The anticyclone is now firmly in control of our weather until at least Wednesday although Monday will probably bring the peak temperature. The centre of the high pressure, current barometric pressure is 1026.5mb, lies over the English Channel that will see the continuation of a westerly breeze today, backing into a more southerly direction on Monday that will increase the heat, and then likely to change significantly into a northerly quadrant on Tuesday before temperatures fall away considerably on Wednesday. By Tuesday we will have had four consecutive days with the maximum above 27C.
The heatwave threshold for the Marlborough area is 27C. The maximum yesterday was above that figure, which will happen again today and also tomorrow. Thus we are technically experiencing a heatwave, which is described as three consecutive days with temperatures rising above the heatwave threshold. The original heatwave thresholds were based on the reference climate period of 1981-2010 and were intended to be flexible and revised in the light of climate change, therefore the heatwave thresholds were revised in 2022, using the most recent 1991-2020 climate averaging period, with the local threshold temperature rising from 26C to 27C. The review saw six counties move from 27C to 28C, one from 26C to 27C and one from 25C to 26C, the areas changed were in the south of the UK and the Midlands.