IMD data showed that between June 1 and July 28, Delhi received an average rainfall of 314.8mm, as opposed to the normal mark of 241.6mm for this period.
While North and North West districts have been lucky in terms of rainfall, North East, which is barely a few kilometres away, is parched and the only deficient district. Both North and North West districts are in the “large excess” category with 72% and 75% surplus rainfall, respectively. North East district has only received 125.2mm of rainfall so far from June 1 onwards compared with the normal mark of 273mm, making it deficit by 54%.
Central district has recorded the most rainfall (435.3mm) during this period, followed by North at 380.7mm. Rainfall is classified as deficit when it is more than -19% and large deficit or large deficient when it is more than -59%. If rainfall is between -19% and 19%, it is classified as normal and between 20% and 59% as “excess”.
South and East districts are verging on the “deficient” category with a deficit of 13% and 10%, respectively. A Met official said the distribution of rainfall, even over a small region such as Delhi, could vary significantly depending on the monsoon trough and cloud formation. “If there is a movement of rain clouds, there may be a passing shower and only some parts of Delhi will receive rain. Distribution is more even if clouds are directly over the city and rain occurs over a period of time,” added the official.
The onset of monsoon was declared on July 13 this year, making it the slowest since 2002. The normal date is June 27. Last year, the monsoon hit Delhi two days early, on June 25. Met officials said the overall forecast for monsoon was expected to be in the “normal” range, with long-term data showing rainfall becoming more evenly distributed by September.