The ongoing heat wave, with temperatures hovering above 45°C in some parts of Delhi, would continue on Tuesday before relief arrives in the form of a thunderstorm, Met officials have predicted.
On Monday, the mercury level in Safdarjung area shot up to 44.4°C. In Palam area, it was exactly a degree higher at 45.4°C. This is higher than Sunday, when the temperature had shot up to 45.2°C at Aya Nagar in south Delhi.
“There won’t be any drastic change in weather at least during the day on Tuesday. We are, however, expecting some dust storm and thunderstorm later in the evening, which might help mercury dip by a few degrees,” said a senior official of the Regional Weather Forecasting Centre.
A Met official said that dust storms and thunderstorms could hit the city and its adjoining districts between Tuesday evening and Wednesday night. There would be squally winds speeding up to 55 km per hour.
“A western disturbance is looming over Jammu and Kashmir and this would trigger some stormy weather in Delhi-NCR,” said the official.
Such thunderstorms are also expected later in the week on Friday and Saturday.
This would bring some respite from the scorching heat and the mercury would drop by at least 2-3 degrees Celsius. The heat wave would fade over the next few days.
“The thunderstorm would cool down air at high altitudes and because of the convection current, this colder air mass would come down to lower levels. As a result of this, the mercury level is expected to plummet to around 40°C by the fag end of the week,” said the official.
Such interim reliefs are normal during this time of the year as western disturbances and cyclonic circulations develop frequently.
“But heat wave conditions would return once the effect of the thunderstorm fades. The mercury would again shoot up to around 44°C triggering another spell of heat wave in the city,” he added.
Heat wave is a condition when the maximum temperature shoots up beyond the 40°C mark and is around 4-5 degrees above the climatic normal. If it goes seven degrees above the climatic normal, it is called ‘severe heat wave’.
The climatic normal of May, which is an average of temperature during the month of May over 30 years, is 39.5°C. So, the Met department declares it as a heat wave whenever temperature in Delhi touches 44°C.
The highest temperature that the city has ever recorded in May was in the year 1944, when the mercury had shot up to 47.2°C.