A blistering heat wave swept through large parts of India for the fifth consecutive day on Tuesday, affecting health and livelihoods.

There is no relief predicted in the affected areas -- Punjab, Haryana, Delhi, Rajasthan, Uttar Pradesh, Gujarat, and northwest Madhya Pradesh -- during the next five days.

The Met Office has issued a red warning for these states, stressing the need for "extreme care for vulnerable people".

It said extreme heat will continue in the lower hills of Himachal Pradesh, safe havens for people escaping the punishing heat in the plains, during the period.

On Tuesday, temperatures remained above 45 degrees Celsius in swathes of Rajasthan, Haryana, Delhi, Chandigarh, and Uttar Pradesh, affecting daily life as many chose to remain indoors in the afternoon.

Parts of Gujarat reeled from the deadly combination of high heat and humidity.

The mercury soared to a blistering 47.8 degrees Celsius in Haryana's Sirsa, making it the warmest place in the country on Tuesday.

In Delhi, temperatures dropped a few degrees compared to the previous days but remained three to five notches above normal for this time of the year.

Officials said the national capital's peak power demand reached an all-time high of 7,717 MW on Tuesday afternoon, as households and offices increased the use of air conditioners.

The power demand is projected to cross 8,000 MW, peaking at around 8,200 MW this summer.

Resident Welfare Associations in Delhi demanded that coolers, fans, cold drinking water, and doctors be made available at polling booths to beat the heat on election day in the national capital.

Polling for the seven Lok Sabha seats in the city will be held on May 25.

The IMD had earlier warned of extreme heat in India during the April-June period, coinciding with the seven-phase Lok Sabha elections that end on June 1.

On Tuesday, the mercury dropped marginally at some places in Himachal Pradesh following thunderstorms and showers even as Una and Neri recorded a high of 42.4 degrees and 42.2 degrees Celsius.

The local weather department said no relief from the scorching heat was likely as the maximum and minimum temperatures are likely to increase by two to three degrees over the next four to five days and stay appreciably above normal.

The mercury rose further in Rajasthan where Pilani in Jhunjhunu continued to remain the hottest in the state with a maximum of 47.2 degrees Celsius on Tuesday.

Normal life was crippled due to the prevailing severe heat conditions.

In view of the scorching heat, Chief Minister Bhajanlal Sharma instructed the Public Health Engineering Department (PHED) and power distribution corporations to ensure an uninterrupted supply of electricity and water.

According to the Met Centre in Jaipur, the maximum temperature is likely to increase by two degrees Celsius in the next 72 hours and there is a possibility of heatwave at most places in the state and intense heat wave at some places in the next two days.

Severe heat waves have impacted a large number of people in parts of India for three years in a row, affecting health, water availability, agriculture, power generation, and other sectors of the economy.

The crippling heat particularly strains low-income households, which often have poor access to water and cooling, and tests the endurance of outdoor workers toiling in the searing sun, forcing them to take frequent breaks.

"The intense heat is affecting my income. The daily earnings have come down from around Rs 1,600 to Rs 1,000. I am not taking any breaks in an effort to cut down the losses; this could affect my health," said 33-year-old Azharuddin, an autorickshaw driver.

According to a World Bank report, India could account for 34 million of the projected 80 million global job losses from heat stress-associated productivity decline by 2030.

With 75 per cent of workers in India experiencing heat-related stress, lost labour from rising heat and humidity could result in a loss of up to 4.5 per cent of India’s Gross Domestic Product (GDP) (equivalent to approximately USD 150-250 billion) by the end of this decade, according to a report by the McKinsey Global Institute.

Experts say outdoor workers, the elderly, and children are at higher risk of heat exhaustion and heatstroke. According to the World Health Organization, more than 166,000 people died as a result of heatwaves between 1998 and 2017.

People are less productive during hot weather, and children struggle to learn.

Parts of India logged record-smashing maximum temperatures in April too, prompting health warnings from government agencies and a few states to suspend in-person classes in schools.

Several places recorded their highest-ever April day temperatures, and at least five people died in the country due to suspected heat stroke during this period.

A group of leading climate scientists last week said similar heat waves could occur once every 30 years, and these have already become about 45 times more likely due to climate change.