The Met Office have issued an amber heat warning for Peterborough and much of England , with the warning currently in place for 48 hours, starting at midnight on Sunday morning and ending at midnight on Monday night.
Trevor Robbins-Pratt, from Peterborough Weather Watch, said temperatures could break records.
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He said: “Thursday will also see some cloud about, but also some brighter spells. temperatures a little cooler at around 23°C or 24°C, but that is still in the warm/very warm category.
“Friday sees the heat building again. Sunny spells and temperatures peaking at 28°C or 29°C
“The weekend and and into the following week, we still see the potential for some very high temperatures. Current modelling suggesting ranges from 33°C to 36°C on Sunday & Monday and we are still seeing some members on some of the model products suggesting temperatures of 39°C+, which would break the current record for the highest temperature officially in the UK.”
Trevor said the average temperature for this time of year was around 23C.
The Met Office warning says: “ Population-wide adverse health effects are likely to be experienced, not limited to those most vulnerable to extreme heat, leading to potential serious illness or danger to life. Government advice is that 999 services should be used in emergencies only; seek advice from 111 if you need non-emergency health advice.
“Substantial changes in working practices and daily routines likely to be required.
“Significantly more people are likely to visit coastal areas, lakes and rivers leading to increased risk of water safety incidents.
“Delays on roads and road closures are possible, along with delays and cancellations to rail and air travel, with potential for significant welfare issues for those who experience even moderate delays.”
Peterborough City Council urged residents to do all they could to keep cool during the hot temperatures – and to look out for vulnerable people, including elderly residents, those with health conditions, babies and those working outside.
A spokesman said: “The top ways for staying safe when the heat arrives are to:
“Close curtains and windows during the day, when it is hotter outside and open them at night
“Drink plenty of fluids and avoid excess alcohol.
“Never leave anyone in a closed, parked vehicle, especially infants, young children, vulnerable adults, or animals.
“Try to keep out of the sun between 11am to 3pm, when the UV rays are strongest.
“If you have to go outside in the heat, walk in the shade, apply sunscreen, cover up with clothing and wear a wide-brimmed hat.
“Avoid physical exertion during the hottest parts of the day.
“Make sure you take water with you if you are travelling.
“During warm weather, going for a swim or taking a cool shower can provide much welcomed relief.
“Please think twice before going into open water to cool-down as this can be dangerous, take care and follow local safety advice"