The maximum temperature recorded in the national capital on Sunday reached 49 degree Celsius, said the India Meteorological Department.
While the national capital's Mungeshpur station recorded a temperature of 49.2 degrees, Najafgarh recorded 49.1 degree Celsius.
The weather agency advised people in northern India to avoid venturing outside their homes unless absolutely essential and to drink plenty of water even if not thirsty.
Weather station at Safdarjung observed a max temperature of 45.6 degrees Celsius while the west part of Delhi reported temperatures ranging between 46 to 48 degrees Celsius.
On May 29, 1944, Safdarjung recorded a max temperature of 47.2 degrees Celsius.
Maximum temperatures reached 47.5 degrees Celsius at Jafarpur, 47.3 degrees Celsius at Pitampura and 47.2 degrees Celsius at Ridge.
Other parts of Delhi observed maximum temperatures rise to 46.8 degrees Celsius at Ayanagar, 46.4 degrees Celsius at Palam and 45.8 degrees Celsius at Lodhi Road, the weather agency said.
In Haryana, Gurgaon recorded the highest temperature today amongst other stations which are 48.1 degrees Celsius and Mukhtsar in Punjab reported 47.4 degrees Celsius.
An 'orange' alert has been issued to caution people about a severe heatwave on Sunday.
The IMD uses four colour codes for weather warnings -- green (no action needed), yellow (watch and stay updated), orange (be prepared) and red (take action).
However, cloudy skies and thunder may provide some relief from the intense heat next week.
The IMD, in its daily weather bulletin, said that on May 15, "Heat wave conditions in most parts with severe heat wave conditions in many parts very likely over West Rajasthan; heat wave conditions in most parts with severe heat wave conditions in some parts over East Rajasthan; heat wave conditions in many parts with severe heat wave conditions in isolated pockets over Madhya Pradesh, Punjab, Uttar Pradesh and Haryana-Delhi; heat wave conditions in isolated pockets over Jammu Division, Jharkhand and Vidarbha."
Cloudy sky may provide some relief from the intense heat next week. "On May 16, thunderstorm accompanied with lightning and hail/gusty winds (speed 30-40 kmph) at isolated places is likely over Jammu and Kashmir, Himachal Pradesh and Uttarakhand; with lightning and hail/gusty winds (speed 40-50 kmph) at isolated places Kerala and Mahe; with lightning/gusty winds (speed 30-40 kmph) at isolated places over Punjab, Haryana, Chandigarh and Delhi, Odisha, Gangetic West Bengal and Andaman-Nicobar Islands and with lightning at isolated places over East Uttar Pradesh, Chhattisgarh, Karnataka, Lakshadweep and Tamilnadu-Puducherry-Karaikal," read the bulletin.
The weather agency advised people with moderate health conditions residing in Northern India to avoid venturing outside their homes unless absolutely essential. "Heat wave could lead to moderate health concern for vulnerable people e.g. infants, elderly, people with chronic diseases. Increased likelihood of heat illness symptoms in people who are either exposed to sun for a prolonged period or doing heavy work," the bulletin said.
"Avoid heat exposure, keep cool. Avoid dehydration. Drink sufficient water- even if not thirsty. Avoid heat exposure, wear lightweight, light-coloured, loose, cotton clothes and cover the head by use of cloth, hat or umbrella etc. Use ORS, homemade drinks like lassi, torani (rice water), lemon water, buttermilk, etc to keep yourself hydrated," the central weather agency said.
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