The University of Reading's observatory recorded 36.9C on 13 August, the town's hottest August day since records began in 1908 and second only to July 2022.

Reading recorded 36.9C on Thursday 13 August, the hottest August day in the town’s 118-year weather record. Only one day has ever been hotter here.

The reading came from the University of Reading’s Atmospheric Observatory, which has kept daily observations since 1908. It beats 36.4C on 10 August 2003, the previous August high, and sits second overall behind 37.6C on 19 July 2022 (University of Reading).

One caveat on the number. The observatory’s climatological table, compiled from manual readings taken at 0900 GMT each day, currently lists August’s highest air temperature as 36.7C (monthly summaries). The 36.9C figure is the one the university published on the day. Either way it clears the 2003 record.

Five of the nine hottest days have come since 2019

Reading’s ten hottest days on record now cluster heavily in the last seven years. The pre-2022 rankings are published by the university’s Department of Meteorology (hot weather numbers).

Hottest days recorded at the University of Reading, 1908 to 2026 Bar chart of the highest air temperatures in the University of Reading record. 19 July 2022: 37.6C. 13 August 2026: 36.9C. 10 August 2003: 36.4C. 9 August 1911: 36.0C. 25 July 2019: 36.0C. 31 July 2020: 35.7C. 3 August 1990: 35.5C. 19 July 2006: 35.3C. 7 August 2020: 35.0C. Reading's hottest days on record Highest air temperature, University of Reading observations since 1908. Scale starts at 34C. 19 Jul 2022 37.6C 13 Aug 2026 36.9C 10 Aug 2003 36.4C 9 Aug 1911 36.0C 25 Jul 2019 36.0C 31 Jul 2020 35.7C 3 Aug 1990 35.5C 19 Jul 2006 35.3C 7 Aug 2020 35.0C Source: University of Reading Department of Meteorology and University of Reading news, 13 August 2026. Graphic by Reading Daily
Five of these nine days have come since 2019. The 1911 and 1990 entries are the only ones from before this century.

Why it got this hot

Dr Rob Thompson, a meteorologist at the university, pointed to a stubborn area of high pressure over western Europe. “As air slowly sinks beneath the high-pressure system it compresses and warms, while at the same time drawing exceptionally warm air northwards from southern Europe and North Africa,” he said.

He added that the dry ground made it worse. With little rain in recent months, more of the sun’s energy heats the soil and the air rather than evaporating moisture from soils and plants.

Dr Akshay Deoras, a climate scientist at the National Centre for Atmospheric Science and the university’s Department of Meteorology, said records are no longer being edged past. “This is yet another example of temperature records not simply being broken by a small margin, but being absolutely smashed,” he said. He described natural patterns such as heat domes working alongside warming caused mostly by burning fossil fuels.

The rain figures are the more alarming ones

The observatory’s own monthly tables show how dry the summer has been in Reading.

  • August so far: 0.0mm of rain to 17 August, which is 0% of the long-run average, and no rain days at all.
  • July: 0.9mm, which is 1% of average, across just two rain days. That is 9.5 rain days fewer than normal.
  • Sunshine: 358.3 hours in July, 175% of average, and 177.4 hours in the first 17 days of August, 168% of average.
  • Temperature: July averaged 21.3C, 3.5C above the 1991 to 2020 average. August is running 3.3C above.
  • Soil: the 10cm soil temperature is averaging 24.5C this month, 6.5C above average.

June was the exception, with 45.0mm of rain, close to a normal month. May managed 20.0mm, 45% of average.

What it means for you

The immediate risk is fire. Royal Berkshire Fire and Rescue Service asked people to help prevent fires in the open on 29 July, after attending more than 250 of them so far this year. Several met the National Fire Chiefs Council’s wildfire criteria. The service says it has dealt with more large outdoor fires, meaning those needing more than four fire engines, this summer than in the previous five years (RBFRS).

Its advice for the current conditions:

  • Do not have a bonfire during prolonged hot, dry weather, and do not use gas or electric weed burners.
  • Keep a barbecue on stable ground, away from sheds, fences, trees and shrubs, and never leave it unattended. Have a bucket of water or sand nearby.
  • Avoid disposable barbecues in dry conditions, put out smoking materials properly, and take glass bottles home.
  • If a fire starts outdoors, do not try to tackle it. Get away and call 999, giving the type of fire and nearby landmarks.

Prevention manager Gail Muirhead put the reason plainly: “When conditions are hot and dry, just a small spark is enough to start a large fire outdoors.”

If you want to cool off, the Thames Lido on Napier Road is a heated 25-metre outdoor pool and is one of the entries in our guide to things to do in Reading, which lists prices for twelve local days out.

Sources