It might not happen often, but when Britain swelters in soaring temperatures it is not everyone's idea of bliss.
While those lucky enough to be on holiday during heatwaves can enjoy the weather in their gardens - or from air-conditioned comfort - what about those who have to work when the mercury rises?
Rules around temperatures in the indoor workplace are covered by the Workplace (Health, Safety and Welfare) Regulations 1992.
What does the law say on employees' rights in hot weather?
The regulations place a legal obligation on employers to provide a "reasonable" temperature in the workplace.
However, while there is a minimum working temperature, there is no statutory upper limit.
Are there any minimum workplace temperatures?
The Approved Code of Practice suggests the minimum temperature in a workplace should normally be at least 16C.
If the work involves "rigorous physical effort", the temperature should be at least 13C.
These temperatures are not absolute legal requirements - the employer has a duty to determine what "reasonable comfort will be" in the particular circumstances.
What about when it gets too hot in the workplace?
The Health and Safety Executive (HSE) says a meaningful figure cannot be given at the upper end of the scale due to the high temperatures found in, for example, glass works or foundries.
In these environments, it said it is still possible to work safely provided appropriate controls are present.
Video: Advice on keeping cool in hot weather
Factors other than air temperature - for example humidity and air velocity - become more significant and the interaction between them become more complex with rising temperatures, the HSE said.
No maximum working temperature - that doesn't sound fair! Is anything being done to change that?
Two MPs are proposing that bosses should be legally forced to provide water, breaks or air conditioning to combat "uncomfortably high" workplace temperatures.
Labour's Ian Mearns (Gateshead) and the SDLP's Mark Durkan (Foyle) believe there is an anomaly in the law.
They say help to cool down should be offered to workers if temperatures soar above 30C (86F) or 27C (81F) if they do "strenuous" work.
They hope a statutory maximum working temperature would secure better working conditions for those in offices, schools, shops, bakeries, call centres and elsewhere - plus protect them from potential health problems.
But is that actually going to happen?
The MPs are now taking their campaign to Parliament and Mr Mearns has tabled an Early Day Motion in the House of Commons.
It states: "That this House notes that workers in the UK lack adequate legal safeguards from working in uncomfortably high temperatures, owing to the lack of a statutory maximum temperature at which employers would have to introduce control measures, such as breaks, access to water or air conditioning."
It also notes: "(This House) calls on the Government to adopt the recommendations of the TUC and joint union Cool It campaign to introduce into law a maximum working temperature of 30C or 27C for those doing strenuous work, beyond which employers would have a statutory duty to introduce effective control measures."
An EDM is a formal motion submitted for debate in the House of Commons, although very few are actually debated.
Are there any other regulations that protect workers during hot weather?
In addition to the Workplace Regulations, the Management of Health and Safety at Work Regulations 1999 require employers to make a "suitable assessment" of the risks to the health and safety of their employees and take action "where necessary and where reasonably practicable".
A Health and Safety Executive spokesman said: "The temperature of the workplace is one of the potential hazards that employers should address to meet their legal obligations.
"Employers should consult with employees or their representatives to establish sensible means to cope with high temperatures."