NEW DELHI — A heat dome anchored over the Indo-Gangetic plain pushed daytime temperatures above 47 degrees Celsius across large stretches of northern India and central Pakistan on Friday, with health officials in both countries reporting at least 84 confirmed heat-related deaths since the start of the week and hospitals in Lahore, Lucknow and Jacobabad extending emergency triage protocols normally reserved for the peak of June.

The India Meteorological Department recorded 47.6 C at Banda in Uttar Pradesh and 47.2 C at Sri Ganganagar in Rajasthan on Friday afternoon, the earliest the country has crossed 47 C at multiple stations since the agency began publishing daily extremes in 1969. In Pakistan, the Met Office logged 48.1 C at Jacobabad and 47.4 C at Sibi, with the federal government declaring a precautionary heat emergency across Sindh and southern Punjab. Both readings, agency officials said, were running roughly six to nine degrees above the climatological average for the first full week of May.

“What we are seeing is a compression of the heat season, not just an extreme inside it,” said Mrutyunjay Mohapatra, director general of the India Meteorological Department, at an evening briefing in New Delhi. “The pre-monsoon window has narrowed, the soil is already moisture-stressed across the central belt, and we are issuing red-category warnings on a calendar week when historically we would still be in orange.”

In Lahore, Punjab’s provincial health department said hospital outpatient clinics had logged more than 6,300 visits for heat exhaustion, dehydration and exertional heat stroke since Monday, with intensive-care units at Mayo Hospital and Services Hospital running at full capacity by midweek. Pakistan’s National Disaster Management Authority confirmed 47 heat-related deaths nationwide, with the largest concentration in Sindh’s interior districts, and said it had positioned mobile cooling units at long-distance bus terminals in Multan, Sukkur and Hyderabad.

The Indian Ministry of Health and Family Welfare reported 37 confirmed deaths across Uttar Pradesh, Bihar, Rajasthan and Madhya Pradesh, with state officials cautioning that the toll typically rises sharply in the days after a heat dome breaks as undiagnosed deaths are reclassified. The All India Institute of Medical Sciences activated a heat-stroke protocol at its Delhi and Patna campuses, instructing emergency rooms to triage suspected exertional heat-stroke patients within three minutes of arrival and to begin aggressive cold-water immersion before laboratory confirmation.

“The mortality you see in the bulletin in week one is rarely the real mortality of a heat dome,” said Dr. Dileep Mavalankar, director of the Indian Institute of Public Health in Gandhinagar and a longtime author of urban heat-action plans. “Excess-death analyses from the 2010 Ahmedabad event and the 2022 northwest event both showed final tolls three to five times the figure announced in the first 72 hours. We should plan as if this week’s number is a floor, not a ceiling.”

Daily-wage construction workers, brick-kiln laborers and street vendors made up the largest share of casualties reported by state health departments, a pattern consistent with prior pre-monsoon heat events. In Lucknow, the Uttar Pradesh Labor Department ordered an enforced midday work pause between 11 a.m. and 4 p.m. at all government-supervised construction sites in eight districts and asked private contractors to follow voluntarily. Similar orders were issued in Karachi by the Sindh provincial government, which closed schools in the city for the second consecutive day.

“My husband worked at the kiln since five in the morning because the contractor said the order does not apply to piecework,” said Rukhsana Bibi, 34, speaking outside Civil Hospital Bahawalpur, where her husband was admitted Thursday with a core temperature of 41.1 C. “He fell down near the stack. The other men carried him out. The contractor said to come back tomorrow if he is better.”

Power demand surged to record May levels in both countries, straining grids already operating with reduced hydropower output after a thin winter snowpack in the western Himalayas. India’s Central Electricity Authority reported peak demand of 247 gigawatts on Thursday evening, the highest ever recorded before May 15, with discoms in Uttar Pradesh, Bihar and Rajasthan instituting rolling load-shedding of two to four hours in rural blocks. Pakistan’s National Transmission and Despatch Company said load-shedding had been extended to six hours daily across rural Sindh and southern Punjab.

The grid stress, public-health officials warned, was a problem of its own, because urban heat-action plans rely heavily on the availability of fans, refrigeration for medication and ice for cooling protocols. “When the lights go out in a rural Bihar clinic at three in the afternoon, the IV bag warms up, the ORS warms up, and the family is fanning the patient with a piece of cardboard,” said Dr. Anjali Sharma, an emergency physician at Patna Medical College. “That is the gap between an action plan on paper and an action plan in the room.”

International climate scientists said attribution analyses were not yet available for the current event but pointed to a now well-documented pattern of earlier and more intense pre-monsoon heat across South Asia. “The 2022 event, the 2024 event, and the event we are watching this week are no longer isolated points,” said Dr. Friederike Otto, a climatologist at Imperial College London and co-founder of the World Weather Attribution group. “They are a trajectory. The signal of human-caused warming on South Asian pre-monsoon heat is now one of the clearest signals we have in the global record.”

In neighboring Bangladesh, the Met Department issued heat alerts for Rajshahi, Khulna and Dhaka divisions but said the dome’s eastern edge had so far spared the country its most extreme readings. The government in Dhaka extended a previously announced school closure through Tuesday and asked employers to permit early-morning and evening shifts in lieu of midday hours.

Forecasters in New Delhi and Islamabad said the heat dome was expected to weaken modestly by Sunday as a westerly disturbance approached the Hindu Kush, though both agencies cautioned that temperatures would likely remain three to five degrees above normal through midweek and that a second pulse of heat could build over the central plains by May 14. Health officials in both capitals said updated mortality figures and a joint Indo-Pakistani technical briefing on cross-border heat warning systems were expected Saturday evening.