Britons will face sweltering conditions this week with a heatwave that could bring highs of up to 33C, and forecasters are warning that a new UK record temperature could be set. On Sunday, the hottest temperature recorded in the UK, according to the Met Office, was 29.5C in Wisley, Surrey. Scotland saw its hottest day of the year, with 28.9C in Fife. Across the UK, crowds flocked to beaches and parks. Further warm weather is still to come this week, with the Met Office saying the UK might have its hottest day this year, with temperatures possibly reaching 33C on Tuesday in London and the south-east. After a slight dip, they could go into the mid-30s next weekend as warm air from Spain and France pushes temperatures up further. Forecasters now believe there is a “30% chance” of a new record being set for the UK. The current is 38.7C in July 2018. Health warnings have been issued by the UK Health Security Agency from Monday until Friday for the south and east of England. It has advised parents to keep their children out of the sun this week. One water company, South West Water, has said it is looking at ways to avoid introducing water restrictions for the first time since a lengthy heatwave in 1976. Maarten van Aalst, the Red Cross climate centre manager, encouraged people to close curtains in rooms that face the sun and keep windows open at night in attempts to keep rooms cooler. He also recommended checking on elderly and vulnerable people to ensure they were staying hydrated. And it could get worse for people who hate the heat, as one long-term forecast from the US has shown temperatures could even get as high as nearly 40C later in July. However, the Met Office said it believed there was only a 10% chance of that being realised. “It’s possible. It’s not outside the bounds of possibility that we’ll see temperatures in excess of 40 degrees,” said Dan Stroud, a meteorologist at the weather bureau. Stroud said: “Towards next weekend temperatures are rebounding and heading back into the 30s. Next weekend we’re looking for temperatures to exceed 32 degrees across England and Wales, but there is a core running from Hampshire through central London and the south-east into East Anglia where temperatures could exceed 35 degrees.”