According the Weston Park weather station, the mercury was already up past 22C by 9am on Monday morning, and it rose as the day went on.
In Sheffield city centre, many enjoyed an outdoor dinner break in the sunshine, while familes with young children made a bee-line to the the water feature in the Peace Gardens, where The Star took pictures with the consent of parents.
Out in the city's parks, sunbathing and picnics were order of the day, as our pictures show.
And it looks like a case of same again for today, with forecasters at the Met Office predicting another sun-kissed day in the city with temperatures expected to be up to 24C.
Health experts are urging people to remember to put on high factor sun cream if they are out in the sun.
1. How did you enjoy the heatwave
Our gallery of 15 pictures shows the many ways people in Sheffield found to enjoy the heatwave Photo: National World
2. Peace Gardens
A mum enjoys the sun with her son in The Peace Gardens Photo: Sheffield Newspapers
4. Family fun
Mum shows her daughter where to look as she cools off in the Peace Gardens Photo: National World