A heatwave saw the mercury breach the 45-degree Celsius mark in parts of capital on Friday and it is likely to get worse on the weekend. At the Safdarjung Observatory, Delhi’s base station, the maximum temperature settled at 42.9 degrees Celsius as against 42 degrees Celsius on Thursday and 41.9 degrees Celsius on Wednesday.
The maximum temperature at Mungeshpur (45.5 degrees Celsius) and Pitampura (45.6 degrees Celsius) settled five notches above normal. The automatic weather stations at Sports Complex and Najafgarh recorded a maximum temperature of 45.7 degrees Celsius and 45.6 degrees Celsius.
The Met office has issued a yellow alert, warning of heatwave at isolated places in the capital on Saturday. The mercury may jump to 44 degrees Celsius at the Safdarjung Observatory, it said. 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).
A heatwave is declared when the maximum temperature is over 40 degrees Celsius and at least 4.5 notches above normal.
A severe heatwave is declared if the departure from normal temperature is more than 6.4 notches, according to the IMD.
Based on absolute recorded temperatures, a heatwave is declared when an area logs a maximum temperature of 45 degrees Celsius.
A severe heatwave is declared if the maximum temperature crosses the 47-degree Celsius mark.
Meanwhile, the Bay of Bengal arm of the south-west monsoon has stirred into action and entered north-eastern parts of the country.
The weather office had upgraded its forecast for a normal monsoon this year on Monday. It said that monsoon rains would be fairly well-distributed across the country, except in north-eastern parts of the country and extreme south-western peninsula.