Summer-like warmth could briefly return to the UK on Sunday, with some areas expected to reach 28°C. Parts of southeast England are forecast to experience temperatures between 27°C and 28°C, while much of England and Wales will see temperatures in the mid-20s. This warming trend is due to a southerly wind bringing in hot and humid air from mainland Europe. As the day progresses, sunny conditions are expected to develop in many areas, further boosting temperatures. In southeast England, central-southern England, and parts of Wales, temperatures are likely to peak in the mid-20s, with some locations hitting 28°C. Meanwhile, southwest England and eastern Wales could see highs of around 25°C, while northern England will remain cooler, with temperatures in the low 20s. In Northern Ireland and Scotland, temperatures in the east are expected to reach about 21°C to 22°C in the afternoon. However, this heat is not expected to last, with cooler conditions returning by Monday. This brief return of warm weather follows a record-breaking summer for the UK, which the Met Office has confirmed as the hottest on record since measurements began nearly 150 years ago. Between May and August, five heatwaves led to widespread drought conditions, wildfires, and travel disruptions. The average temperature for June, July, and August was 16.5°C, surpassing the previous record of 16.1°C set in the previous year. Earlier in the summer, the Met Office had predicted the UK was on track for its hottest season if temperatures remained near average for the rest of August. Final figures for the month are expected to confirm this record. The highest temperature recorded this summer was 38.1°C at Kew Gardens on August 13, which did not break the all-time UK high of 40.3°C recorded in Lincolnshire in July 2022. However, this summer saw several other records broken, including three days where temperatures reached 37°C or higher. Prior to 2026, temperatures above 37°C had only been recorded nine times in the UK, with three of those occurrences happening this year.