'Monsoon' misery for IMD as rains elude Kerala; Skymet, weather geeks question arrival claim

We Indians keep a close eye on monsoon progress each year, which is very vital for the Indian economy and agriculture perspective. The arrival of seasonal rainfall after harsh summers is welcome with great pomp. As per the national forecasting agency, the rainy season stretches from 1 June to 30 September chronologically. The arrival of monsoon over the Indian mainland starting from Kerala is announced by Indian Meteorological Department, precisely IMD, keeping in mind the set criteria based on various parameters including rainfall, winds and Outgoing Longwave Radiations (OLR). This year, the monsoon arrival was announced by the national agency on 29 May as against the earlier predicted date of 27 May, yet 3 days in advance. But the controversy arose when the country’s largest private weather forecaster Skymet India objected to the arrival in view of ignorance of set criteria overlooked by IMD. Many budding  weather enthusiasts and bloggers also supported Skymet as the widespread rain eludes Kerala. The set criteria for announcement of monsoon arrival:

• If after 10th May, 60 per cent of the available 14 stations, viz Minicoy, Amini Divi, Trivandrum, Punalur, Kollam, Alappuzha, Kottayam, Kochi, Thrissur, Kozhikode, Thalassery, Kannur, Kudulu, and Mangalore report rainfall of 2.5mm or more for 2 consecutive days, the onset over Kerala be declared on the 2nd day, provided the winds and OLR criteria also remains in concurrence.

• Wind Field: Depth of westerly winds should be maintained up to 600 hPa, in the box 0°-10°N and 55°-85°E. The zonal wind speed over the area bounded by 5°-10°N and 70°-80°E should be of the order of 15-20 knots at 925 hPa.

• OLR: INSAT derived OLR value should be below 200 Watt/ sq. meter in the box confined by 5°-10°N and 70°-75°E.

Skymet argues IMD overlooked its own set of specified criteria for declaring onset of monsoon. According to Skymet, though OLR and Winds were established, the main norm of rainfall fell short on 28 May and 30 May. “Onset conditions were fulfilled only for one day, 29thMay. Day prior (28th May) and day later (30thMay), merely Read all the Latest News , Trending News ,  Cricket News , Bollywood News , India News and Entertainment News here. Follow us on Facebook, Twitter and Instagram.