Delhi Shatters 88-Year June Rainfall Record with Recent Downpours

Delhi experienced 228.1 mm of rainfall on Friday, the highest for June since 1936, with more rain expected over the weekend. The Safdarjung Observatory recorded this rainfall in the 24 hours ending at 8:30 am, surpassing the June average of 74.1 mm.

The India Meteorological Department (IMD) attributed the heavy rainfall to several factors. "Considering the monsoon circulation, the advance of the monsoon was stalled over eastern India for quite a long time due to a weaker monsoon current over the Bay of Bengal," the IMD stated.

Weather Patterns and Predictions

The IMD explained that from June 25 onwards, an upper air cyclonic circulation developed over central and adjoining north Bay of Bengal, strengthening the monsoon current. Simultaneously, the Southwest Monsoon current over the Arabian Sea intensified with increased wind speed and a stronger offshore west coast trough.

On June 27, a low-pressure area formed over northwest Bay of Bengal and adjoining north Odisha-Gangetic West Bengal coasts, enhancing warm and moist air advection towards Northwest India, including Delhi. An anticyclone centred northeast of Delhi provided strong upper-level divergence supporting lower-level wind convergence.

Historical Rainfall Data

Delhi's rainfall on Friday marked its second-highest for June since 1936. The highest was recorded on June 24, 1936, with 235.5 mm. Other significant records include 191.6 mm on June 30, 1981, and 139.7 mm on June 24, 1933.

The IMD's data shows that after 1936, this is the highest rainfall in Delhi in the last 88 years and the second highest from 1901 to 2024. The weather station at Lodhi Road logged 192.8 mm of rainfall in the same period ending at 8:30 am.

Impact on Delhi

Extreme weather events are becoming more frequent in Delhi. On Friday alone, one-third of Delhi's total monsoon rainfall was recorded. The city typically receives around 650 mm of rainfall during the entire monsoon season.

The IMD has forecast generally cloudy skies with moderate to heavy rain and thunderstorms for Saturday, accompanied by gusty winds reaching up to 30-40 km/h. An orange alert has been issued for the city.

Temperature and Humidity Levels

On Friday, Delhi's maximum temperature was recorded at 32.5 degrees Celsius, five degrees below normal. Relative humidity ranged between 72% and 100%, according to an IMD bulletin.

The IMD issues four colour-coded warnings: green (no action needed), yellow (watch and stay updated), orange (be prepared), and red (take action). The maximum and minimum temperatures are expected to hover around 32 and 25 degrees Celsius respectively.

The weather department also shared total monthly rainfall data for June at Safdarjung station from 1901 to 2024. June 2024 recorded the third-highest rainfall in this period at 234.5 mm, following records of 415.8 mm in 1936 and 399 mm in 1933.

The mesoscale convective activity over Delhi NCR led to intense thunderstorms and heavy rainfall early on June 28th. This activity was supported by thermodynamic instability favourable for thunderstorms.