Late on Thursday night, amid a forecast of thunderstorms, some suburban pockets of Mumbai received scanty showers. Beyond the city’s limits, however, the weather was far more dramatic.

Heavy rain and hail activity battered areas across Maharashtra in unusually intense bouts of pre-monsoon spells. On Thursday, Pune recorded its wettest April since 1896, while parts of Marathwada and Vidarbha too have been battered by incessant showers over the past 3-4 days.

According to scientists from the India Meteorological Department (IMD), thunderstorms and heavy pre-monsoon showers have swept areas that fall along the line of discontinuity, an area where there is a sudden change in wind direction or speed, often leading to unstable weather conditions.

“At present, there is a western disturbance (WD) system which ushered in westerly winds. At the line of discontinuity, there is a change in air mass, meaning that the westerly winds interacted with easterly winds,” said Sushma Nair, a scientist at IMD Mumbai.

“This type of air flow is prominent in Madhya Maharashtra and Marathwada. Therefore, the areas in these regions are experiencing thundershowers and rain activity,” she explained.

However, Mumbai is beyond the radar of this line of discontinuity, thereby leaving it much drier than its neighbouring regions. “It was only poised to receive light rain because of the moisture incursion, which was spurred by the WD system,” a scientist said.

In its forecast for the Mumbai Metropolitan Region, the IMD has eliminated the possibility of rain in the coming days. In fact, scientists said that heavy showers are unlikely to sweep the Mumbai region until late May.

“Thunderstorms are a very common feature during the summer months. However, heavy rain activity is a rare occurrence for Mumbai in the month of April,” a meteorologist told The Indian Express.

Historical records from the weather bureau show that Mumbai’s wettest April was recorded in 2023, at a mere 14 mm of rainfall.

While rain will continue to elude Mumbai, the IMD has forecast normal temperatures for the city in the next week. According to the weather bureau, maximum temperatures in the city are likely to oscillate between 32-33°C till April 9, while night-time temperatures may hover around 23°C.