In the ongoing South West Monsoon, India received 44 year old high surplus rainfall of 327 mm in just concluded Aug 2020, 26.6% above normal rainfall of 258.2 mm. This helped the total June-Aug 2020 rainfall to achieve 10% surplus, with actual rainfall 780.3 mm, 69.9 mm higher than normal rainfall of 710.4 mm. In June the country received 18% above normal rainfall and in July it received 9.9% below normal rainfall, the rainfall at the end of June was just 1.1 mm above normal. Thus almost the entire surplus rainfall is thanks to the rainfall during Aug 2020. The rainfall distribution has however, been far from normal that these figures suggest, as we can see from the state wise and district wise figures below.Continue reading “District wise rainfall in June-Aug 2020 in India”
Here we present the rainfall figures from India Meteorological Department in the just concluded month of June 2020, the first month of SW Monsoon 2020. The overall rainfall at all India level in June 2020 was 196.2 mm, 18% above normal rainfall in the month at 166.9 mm. It was 33% deficit last year.
This is India’s wettest June 12 years, The Times of India reported on July 1, 2020. Agriculture Ministry Data shows that sowing is 68% higher at 31.56 m ha. The June rainfall was 202 mm in 2008, the rainfall this year is the highest since then. All four IMD regions (Northwest, Central, South, East & NE) have recorded surplus rainfall, the surplus is the highest in Central (30.5% surplus) and E-NE (15.7%) regions. North West India had the lowest surplus at 3.5%. IMD Head Mrutyunjay Mohapatra said that whole of India was covered by monsoon on June 26, 12 days ahead of the normal date of July 8.
State wise rainfall Three states had large excess rainfall (above 60% surplus rainfall), namely Bihar, Madhya Pradesh and Sikkim. Eight states/UTs (Union Territories) had excess rainfall (20-59% surplus): Assam, Meghalaya, UP, Chhattisgarh, Maharashtra, Telangana, Andhra Pradesh & Andaman and Nicobar. Nine had deficient rainfall (20-59% deficit): Lakshadweep, Mizoram, Manipur, J&K, Ladakh, Himachal Pradesh, Delhi, Dadar & Nagar Haveli. Rest of India had Normal Rainfall. Continue reading “District Wise rainfall in India in June 2020”
IMD’s 1st Long Range Forecast for SW Monsoon 2020 on Apr 15, 2020[i] says:
– Rainfall will be normal (100% of LPA: Long Period Average of 88 cm). IMD says Neutral El Nino Southern Oscillation prevails in Pacific Ocean and Neutral Indian Ocean Dipole conditions prevail in Indian Ocean, likely to remain throughout the monsoon as per most models, some indicate weak La Nina conditions in Pacific Ocean in second half of monsoon.
– FORECAST BASED ON MONSOON MISSION COUPLED FORECASTING MODEL There is high probability (70%) of monsoon rainfall being above average to excess (over 104% of normal)
– FORECAST BASED ON OPERATIONAL STATISTICAL ENSEMBLE FORECASTING SYSTEM: 9% probability of Deficient monsoon (Over 10% below normal); 20% probability of below normal (90-96% of normal) rainfall; 41% probability of normal monsoon (96-104% of normal rains); 21% probability of above normal (104-110% of LPA rains) and 9% probability of excess (over 110% of normal) rains.
India’s most important season from water point of view, the June-Sept South West Monsoon has just ended officially on Sept 30, 2018. India Meteorological Department (IMD) reported that India received 804 mm rainfall in these four months of monsoon 2018, compared to normal rainfall of 887.5 mm. So Monsoon 2018 rainfall was 9.4% below normal, also proving IMD forecast wrong. Continue reading “River Wise Rainfall in Monsoon 2018”
India’s most important season, the June-Sept South West Monsoon has just ended officially on Sept 30, 2017. India Meteorological Department (IMD) reported that India received 841.3 mm rainfall in these four months of monsoon 2017, compared to normal rainfall of 887.5 mm. So Monsoon 2017 rainfall was 5.2% below normal.
The standard dominating reporting of monsoon rainfall figures in India is either state wise or sub division wise[i]. Accordingly, IMD reported that 25 sub divisions reported normal rainfall, 5 sub divisions[ii] reported excess rainfall and six sub divisions[iii] reported deficit rainfall, as can be seen from accompanying IMD sub division wise map of 2017 monsoon rainfall figures. Continue reading “River Wise Rainfall in Monsoon 2017”
India Meteorological Department of Pune (IMD) functioning under Ministry of Earth Sciences has recently (Nov 2016) published a study titled “Rain water harvesting potential for different locations in state of Maharashtra”.[i] The study was undertaken to assess the potential of roof top rain water harvesting based on mean annual rainfall. The need for the study was prompted by requests from a number of NGOs for information on how much rain can be harvested in Maharashtra during a good rainfall.[ii] The study basically estimates volume of rainwater (in liters) that could be harvested per sqft of roof area at 326 locations across Maharashtra where IMD stations are located.
Though this study is an important step, there are a number of ways in which such a study, which IMD plans to eventually conduct for other states as well, can be improved, in addition to a number of limitations that the study has, as elaborated subsequently. Continue reading “IMD estimates rainwater harvesting potential of Maharashtra”