Advanced weather modeling suggests that temperatures in the UK could surge back to 23°C on May 20, affecting 27 counties across the country. After experiencing highs of 26°C last week, temperatures have recently dipped below 20°C, with forecasts indicating possible overnight lows of -5°C in parts of Scotland. The GFS weather model highlights that south-east England may see the warmest conditions, while other regions like East Anglia and areas near the England-Wales border could reach 21°C. The Met Office anticipates a mix of low-pressure systems leading to showers and rain, particularly in the northwest, but also notes the likelihood of dry and warm spells, especially in the south. Overall, temperatures are expected to remain close to seasonal averages, with potential for higher readings later in the month as high pressure may settle to the north or west of the UK.