Mumbai heatwave warning conditions continued for a third consecutive day on Wednesday, with the India Meteorological Department issuing a yellow alert as maximum temperatures rose to 37.8°C at Santacruz and 36.4°C at Colaba. The readings were 4.1°C and 3.2°C above normal respectively, with hot and humid conditions forecast in isolated areas.
The IMD has issued another heatwave warning for October 15, while October 16 is expected to remain hot and humid. The weather bureau has forecast light to moderate rain and thundershowers in Mumbai and Thane on October 17 and 18, which could provide temporary relief from the current spell.
The latest temperatures follow a sharp rise earlier in the week. Mumbai recorded a maximum of 38°C a day before Wednesday, making it the second-hottest October day in 11 years, according to the report. The mercury had touched 38.2°C on Monday, the highest October maximum recorded in the city during the same period.
An IMD official said the prolonged heat was linked to an anticyclone that had triggered the first heatwave warning on October 9 and had since shifted slightly northwards. An easterly wave is also influencing the region, with temperatures expected to reach 37.8°C on Thursday. The official said this could result in seven consecutive days with temperatures above 37°C, describing the stretch as unusually oppressive for Mumbai.
The official said Mumbai typically experiences spells of two or three days of high temperatures, but a continuous stretch of six or seven days is not normal. The easterly wave, described as a weather system characterised by a trough travelling from east to west, can interact with weather systems approaching from the west and trigger intense thunderstorms. Its role in prolonging the current hot spell, particularly during a strong El Niño year, requires further examination, the official said.
Akshay Sunil, vice-president of WeatherEx Pvt Ltd, said the heat over Mumbai was part of a broader warm spell across western India. According to Sunil, a high-pressure circulation and easterly to northeasterly winds were limiting the usual cooling sea breeze, while clear post-monsoon skies were allowing stronger daytime heating. High humidity was adding to the discomfort.
WeatherEx’s extended outlook suggests that above-normal temperatures may continue through at least October 22. Sunil said localised light showers could bring temporary relief after October 22 in parts of the Konkan region. The immediate forecast for Mumbai and Thane, however, points to possible rain and thundershowers on October 17 and 18, following another day of heatwave conditions.
