 Complete the following phrase:  Since records began, the lowest temperature ever recorded in the Liverpool and Merseyside area is on 19 December 2010, and the highest temperature recorded is on 2 August 1990. Although, during the 2006 heat wave, a temperature of was supposedly recorded at Liverpool John Lennon Airport on 19 July 2006. The highest daily minimum temperature is reported on 29 July 1948, and the lowest daily maximum temperature is on 20 December 2010. On average, the amount of air frost days per year is below the national average, and in winter, snow is fairly common, but heavy snow is rare. Rain is also a common occurrence in the city, but droughts can become a problem in the summer, most recently in the 