Where to start with the hottest, driest and sunniest month in our records!

Firstly, the heatwave. This July has been comparable to the former hottest July in our 42 years of records, in 2022 just four short years ago. The hottest day was Thursday 9th, peaking at 36.6°C, though this was short of the 38.8°C recorded in July 2022, still our hottest ever day. Nevertheless the overall mean for the month was 21.6°C, making July the hottest month overall in our records. The average day maximum was 28.6°C, also the hottest in our records, and the lowest day maximum at 21.5°C was the second highest on record. The seven days when the temperature exceeded 30°C also equalled July 2022. Somewhat surprisingly, however, there were no ‘Tropical nights’ (nights where the temperature never falls below 20°C) this month.

As for the rain… What rain? It rained on just one day, Sunday 26th, the first rain for 29 days (just short of our longest ever dry spell), a paltry 1.0mm. This was the first month with only one rainy day, the lowest monthly total on record (equalling April 2010), and the lowest ever day maximum.

After our wettest ever January and our 6th wettest February, over the five months from March to July we’ve had just 29% of our long term average rainfall.

We’ve only three years of detailed sunshine records, but unsurprisingly this was the first month when we’ve recorded sunshine on every day of the month. The total for July was 272.6 hours, an amazing 80% up on the past two Julys! The strongest sun was 1234 watts per square metre recorded on the hottest day, the 9th, no surprise there, and much higher than the past two Julys.

High pressure has of course dominated the weather for some weeks now, with a monthly average of 1019.3mb this July, second highest in our July records after 2022. The only dip in the pressure came as a trough delivered our one brief shower!

The wind has generally been light, the maximum gust of 24mph (Force 5) being the third lightest for July. And with high pressure usually nearby, but drifting back and forth across the country, the winds have come from just about any direction over the month as a whole.

Gardens, fields, the water table, are all crying out for rain, but August is starting out still warm and dry. Will there be any to come later in the month? In the famous drought year of 1976 – and your correspondent is old enough to remember commuting on stifling Tube trains to a non-air-conditioned office – the drought finally broke on the August Bank Holiday!

Measure	Unit	Minimum	Average	Maximum	Average min	Average max	Total
Relative humidity	%	25	64	92
Temperature	°C	9.6	21.6	36.6	15.2	28.6
Wind source (most common/highest gust)	Sector		N	NW
Wind speed	mph		2.6	24		15.4
Rain daily accumulation	mm		0.0	1.0			1
Barometric pressure	hPa	1002.6	1019.3	1028.6
Solar irradiance during daylight	W/m² kWh/m²		354	1234		901	180.2
Sunshine (according to University of California formula)	Hours		8.8	12.1			272.6