India Meteorological Department’s skill on Seasonal Forecasting System, is better than other countries in the world – Dr. Harsh Vardhan
During the current year, normal/ above normal rainfall has been predicted by many forecasting agencies including India Meteorological Department (IMD). No forecast assessment for pre-monsoon season is issued by any agencies.
According to the IMD’s Operational Long Range Forecast (LRF) for the 2016 Southwest monsoon rainfall, quantitatively the monsoon seasonal rainfall is likely to be 106% of the Long Period Average (LPA) with a model error of ± 5%. The LPA of the seasonal rainfall over the country as a whole for the period 1951-2000 is 89 cm. Climatologically, the monsoon is expected to reach South Kerala either end of May or early days of June(by 31st May ± 4 days), the forecast for which will be issued on 15th May, 2016. Further, the forecast for monsoon onset over Kerala has been within the forecast limits during all the 10 years (2005-2014), since issuing of operational forecast for the event started in 2005.
Forecasts for 2016 southwest monsoon season rainfall over the country as a whole, as received from some of the private forecasting agencies and several foreign agencies, is as given below:
| S.No. | Institutes | Forecast | |
| 1 | Skymet | 105% (with an error margin of ±4%) | |
| 2 | Weather Risk Management Services | Roughly more than 104% in most parts of the country, except the northeast and with well-distributed rainfall over the country | |
| 3 | Onkari Prasad (Retired IMD) | 100% | |
| 4 | Center for Disaster Mitigation Jain University, Bangalore | 98.2% ± 5.52% | |
| 5 | ECMWF,UK | Coupled Model | Above Normal rainfall is most likely over some parts of Northwest India and some parts of southeastern Peninsular India.Normal rainfall is most likely over most of the remaining parts of the country. |
| EUROSIP Multi Model Ensemble(MME): 3 Coupled Models | Normal rainfall over most parts of the country | ||
| 6 | International research Institute for climate and Society, USA | Climatological probabilities for most parts of the country except northern parts of the country where below normal is most likely. | |
| 7 | Japan Agency for Marine-Earth Science and Technology (JAMSTEC) | Negative rainfall anomalies over northern parts of the country, central India and most parts of west coast. Positive rainfall anomalies are predicted over remaining areas with highest magnitudes over northeast India. | |
| 8 | APEC Climate Center | Normal rainfall is most likely over east and northeast India. Above normal is most likely over remaining parts of the country. | |
| 9 | Met Office, UK | Above normal rainfall is most likely over most parts of the country. | |
IMD, following the review of the old forecasting system, introduced the present LRF models in 2007. This effort has led to appreciable improvements in the efficiency of models in making better forecasts. It may be mentioned that the skill of IMD’s present seasonal forecasting system, for India as a whole, is better than other countries in the world. There have been model developments for better skill of prediction through the Monsoon Mission program of the Ministry of Earth Sciences (MoES).
The Variation of all India rainfall during monsoon for the last 20 years is presented in the table below:
| Year | Forecast | Actual (% of LPA) | |
| 1994 | 92% of LPA ± 4% | 110 | |
| 1995 | 97% of LPA ± 4% | 100 | |
| 1996 | 96% of LPA ± 4% | 102 | |
| 1997 | 92% of LPA ± 4% | 102 | |
| 1998 | 99% of LPA ± 4% | 106 | |
| 1999 | 108% of LPA ± 4% | 96 | |
| 2000 | 99% of LPA ± 4% | 92 | |
| 2001 | 98% of LPA ± 4% | 92 | |
| 2002 | 101 of LPA % ± 4% | 81 | |
| Issued in April | Issued in June | ||
| 2003 | 96% of LPA ± 5% | 98% of LPA ± 4% | 102 |
| 2004 | 100% of LPA ± 5% | 100% of LPA ± 4% | 87 |
| 2005 | 98% of LPA ± 5% | 98% of LPA ± 4% | 99 |
| 2006 | 93% of LPA ± 5% | 92% of LPA ± 4% | 99 |
| 2007 | 95% of LPA ± 5% | 93% of LPA ± 4% | 105 |
| 2008 | 99% of LPA ± 5 | 100% of LPA ± 4 | 98 |
| 2009 | 96% of LPA ± 5 | 93 % of LPA ± 4 | 78 |
| 2010 | 98 % of LPA ± 5 | 102 % of LPA ± 4 | 102 |
| 2011 | 98 % of LPA ± 5 | 95 % of LPA ± 4 | 102 |
| 2012 | 99 % of LPA ± 5 | 96 % of LPA ± 4 | 93 |
| 2013 | 98 % of LPA ± 5 | 98 % of LPA ± 4 | 106 |
| 2014 | 95 % of LPA ± 5 | 93 % of LPA ± 4 | 88 |
| 2015 | 93% of LPA with a model error of ± 5% | 88% of LPA ±4% | 86% |
Under the National Monsoon Mission initiative institutions like Indian Institute of Tropical Meteorology (IITM), Pune, IMD, Indian National Centre for Ocean Information Services (INCOIS), Hyderabad and National Centre for Medium Range Weather Forecasting (NCMRWF), NOIDA, have developed a coupled ocean-atmospheric climate model for,
- improved prediction of the monsoon rainfall on extended range to seasonal time scale (16 days to one season) and,
- improved prediction of temperature, rainfall and extreme weather events on short to medium range time scale (up to 15 days), so that forecast skill gets quantitatively improved further for operational services of IMD.
This was stated by the Union Minister for Science & Technology and Earth Sciences, Dr. Harsh Vardhan in a reply to a question in the Lok Sabha today.