The national capital on Saturday recorded the this season's hottest day so far with the mercury reaching 43.7 degrees Celsius, the India Meteorological Department (IMD) said and issued a 'red alert' predicting severe heat in many parts of the city over the next two days.

Mungeshpur recorded the highest maximum temperature in the city at 46.8 degrees Celsius, followed by Najafgarh noting 46.7 degrees Celsius, Pitampura 46.2 degrees Celsius, Pusa 46 degrees Celsius, Aya Nagar 45.2 degrees Celsius, and Palam 44.2 degrees Celsius.

Delhi's base weather station at Safdarjung recorded a high of 43.7 degrees Celsius, which was more than three notches above the season's normal and the highest maximum temperature this season so far.

The weather office predicted heat wave conditions in many parts of Delhi and sounded a red alert. The department has also forecast a partly cloudy sky with strong surface winds at a speed of 25 to 35 kmph.

Mentioned the impact of the heat wave in its seven-day forecast, the IMD urged extreme care for vulnerable people.

There is a very high likelihood of developing heat illness and heat stroke in people of all ages, and a health concern for vulnerable individuals such as infants, the elderly, and those with chronic diseases, the department said.

"Avoid heat exposure and ”keep cool. Avoid dehydration," it added.

The MeT suggested drinking sufficient water and using ORS or homemade drinks like lassi, torani (rice water), lemon water, and buttermilk to stay hydrated.

A heat wave is defined when the maximum temperature at a weather station reaches at least 40 degrees Celsius, with a deviation from the normal of at least 4.5 degrees or more, according to the IMD.

A severe heat wave is declared when the maximum temperature is 6.5 degrees above the normal.

The relative humidity oscillated between 70 per cent and 18 per cent on Saturday. The minimum temperature was noted at 27.1 degrees Celsius, 0.6 notch above the season's average, according to the IMD.

For Sunday, the MeT has predicted the maximum and minimum temperatures to likely reach 44 and 28 degrees Celsius, respectively.

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