The warm weather is not expected to abate over the weekend with highs of 24C possible in South East Wales and around the Bristol Channel on Saturday and Sunday.
Other areas around the UK can expect temperatures reaching the late teens and early 20s.
Met Office meteorologist Simon Partridge said high temperatures for the bank holiday weekend were a rarity in what was expected to be dry.
“We are slowly getting there. Touches of summer,” Partridge said. “I guess for a holiday weekend it’s pretty unusual to be this dry and sunny, so we’re not doing too bad.”
Rain is unlikely to bother the UK in the coming days, and the Met Office’s deputy head of forecasts, Steven Keates, says indications are that bright dry weather is likely to continue for the most part, with little rain during the next week.
The highest temperature in the UK on Friday was at Bainbridge, where it hit 22.6°C.
However, forecasters say the hottest day is yet to come, with temperatures expected to reach 24°C.
The highest temperature of 2023 was recorded in Cardiff on Monday with a pleasant 23.4°C.
Met Office chief meteorologist Paul Gundersen said: “The jet stream settling north of the UK is keeping unstable weather systems at bay and allowing high pressure to dominate, bringing fine weather to the vast majority of the UK. United.
“The current position of the high pressure means that we will see airflow from the west over the UK, a cooler direction than if the air were rising from the south and areas such as Spain or Africa.
“Therefore, it is not likely that we will reach heatwave conditions, but temperatures will remain warm, reaching the low 20s for many, particularly in the southwest and south Wales.”
Meanwhile, travel experts warn of a busy time on the roads.
RAC spokesman Rod Dennis said: “We hope families make the most of the good weather in the coming days as we are forecasting the busiest bank holiday at the end of May since before the pandemic.
“Over the next week and half quarter in many parts of the UK day trips will also be a big feature, with popular routes to the coasts and countryside becoming more crowded.
“Leaving early in the morning or delaying trips until late at night are the best ways to avoid the inevitable delays.
“No one wants a breakdown to come between them and their time with family and friends, yet many of the jobs our patrol cars will be out on are entirely avoidable if drivers complete a few checks before hitting the road. .
“Making sure the oil and coolant levels are where they should be is a must, as is checking that the tires are free of damage and properly inflated.”