1.8.18

Monsoon tracker

In July, Mumbai got drenched with 1,137 mm of rain, which is not only more than the average requirement for the month (840.7 mm), but also the second highest monthly rainfall for July since 2012. The maximum rainfall—864.5 mm—was recorded in the first 10 days of the month. Then, there was a lull. Since 2012, the highest July rainfall was recorded in the year 2014—1,468.5 mm. Last year, the city received 869.7 mm of rain in July.

However, monsoon across the country fell below expectations in July, which ended with a rain shortfall of 6%. With monsoon becoming inactive in central and south India, the all-India rainfall deficit grew in the past six days from 2% to 6%.

In Mumbai, weathermen expect monsoon to pick up again from August 6-7, with a low pressure area expected to form in the Bay of Bengal.

Uncertainty, however, continues over monsoon’s performance across the country in August and September. August is likely to begin with the monsoon in a weak phase, with the trough close to the Himalayas—it usually brings showers in the western Himalayan states and not much in the northern plains. Fears continue over an evolving El Nino, an abnormal warming the east equatorial Pacific waters that usually has negative spinoffs for the southwest monsoon.

Maharashtra, along with other places in central India, is set for moderately dry to severely dry conditions till August 22.

The India Meteorological Department provided this forecast based on the analysis of the extended range outlook of the standard precipitation index. The SPI, which measures drought based on rainfall received, has shown negative rainfall abnormalities over many parts of the state till August 22. The SPI is negative for drought and positive for wet conditions.

Pulak Guhathakurta, the head of the climate data management and services at IMD, Pune, said as per the SPI’s outlook, parts of Madhya Maharashtra, Konkan, Vidarbha and Marathwada, among other regions in central India like Telangana, Chhattishgarh, Odisha, and west India including parts of Gujarat may have moderately dry to severely dry conditions till August 22. The forecast showed that a portion of south Maharashtra may also experiemce extremely dry conditions.

The SPI inidicated wet conditions for none of the regions in Maharashtra.

IMD also monitors the incidence, spread, intensification and cessation of drought with the aridity anomaly index. As per aridity conditions monitored by IMD from July 23 to July 29, most of the northern, eastern and southeastern parts of Madhya Maharashtra, western and southern Marathwada, among other regions in the country, were hit by severe arid conditions. 

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