Lok Sabha Question No. 621 (UNSTARRED), answered on 2025-12-03
Subject: Operational Forecasting and Monitoring Mechanisms
Ministry: EARTH SCIENCES
Asked by: Shri Bibhu Prasad Tarai, Dr. Vinod Kumar Bind

## GOVERNMENT OF INDIA MINISTRY OF EARTH SCIENCES LOK SABHA UNSTARRED QUESTION NO. 621

## TO BE ANSWERED ON WEDNESDAY, 3 RD  DECEMBER, 2025

## OPERATIONAL FORECASTING AND MONITORING MECHANISMS

## 621.    DR. VINOD KUMAR BIND: SHRI BIBHU PRASAD TARAI:

Will the Minister of EARTH SCIENCES be pleased to state:

- (a) the details of methodology  and  tools  currently used by India  Meteorological Department (IMD) to provide seasonal prediction of monsoon rainfall;
- (b) the percentage of accuracy of IMD's operational forecasting for the 2025 SW Monsoon season rainfall;
- (c) the details of the performance of IMD's operational seasonal forecasting since multimodel ensemble forecasting was implemented;
- (d) the steps taken by the Government in improving the monitoring & forecasting of the weather and climate hazard; and
- (e) the various weather and climate services provided by IMD for south Asian countries?

## ANSWER

## THE MINISTER OF STATE (INDEPENDENT CHARGE) FOR MINISTRY OF SCIENCE AND TECHNOLOGY AND EARTH SCIENCES (DR. JITENDRA SINGH)

- (a) Currently,  the  India  Meteorological  Department  (IMD)  is  using  both  the  statistical forecasting system and the newly developed Multi-Model Ensemble  (MME) forecasting  system  for  issuing  monthly  and  seasonal  operational  forecasts  for  the southwest monsoon rainfall over the country. The MME forecasting system is based on the coupled global climate models (CGCMs) from various global climate prediction centers,  including  IMD's  Monsoon  Mission  Climate  Forecasting  System  (MMCFS) model. These systems  provide probabilistic  forecasts  of  rainfall  and  temperature  at various spatial  and temporal scales, including all-India,  regional,  and sub-divisional levels.
- (b) IMD's operational qualitative forecast for the 2025 Southwest Monsoon season rainfall (June  to  September)  over  the  country  as  a  whole  issued  during  both  the  first  stage (issued on 15 th April) and second stage forecast (issued on 27 th  May), was above normal (i.e., 105 to 110% of LPA of the Long Period Average (LPA) ). Quantitatively, the IMD forecast for the 2025 south-west monsoon season rainfall issued during the first and second stage forecasts were 105% of LPA with a model error of ±4%  and 106% of the LPA with a model error of ±4% respectively. The realised 2025 seasonal monsoon rainfall over the country as a whole was 108% of its LPA. Thus, the realised seasonal rainfall  for 2025 was within the forecast limits, and both the first and second stage forecasts were accurate. Further details on the verification of monthly and region-wise forecasts are given in Annexure-1, which clearly demonstrates that these forecasts were accurate for the 2025 season.
- (c) Due to the implementation of the Multi-Model Ensemble-based forecasting strategy in 2021, the accuracy of monsoon predictions has shown marked improvement. During the period 2021-2024, the average absolute error in the operational forecast was 2.28% of the LPA, while the average absolute error during the preceding four years (20172020) was significantly higher, at 7.5% of the LPA. Overall, the All-India south-west monsoon rainfall  forecasts (June-September) during 2021-2024  were notably  more accurate. A summary of various forecasts issued during the monsoon season, along with their verification over the last 5 years since 2021, is provided in Annexure-2.
- (d) Various steps have been taken by the Government for improving the monitoring & forecasting  of  the  weather  and  climate  hazards.  There  has  been  a  significant improvement  in  the  satellite,  RADAR-based  monitoring  system,  surface  and  other observational networks, and forecasting capability over the past decade.
-  The number of Rainfall monitoring stations increased from 3980 in 2015 to 6727 in 2025.
-  Satellite  and  RADAR-based  monitoring  has  increased  manifold.  Currently,  6 Channels  in  INSAT 3-D are  providing  30-minute  gap  cloud  pictures  and  water vapour, wind-related products at a very high resolution of up to 1 km. In 2014, a total of 15 DWRs were operational across India, while in 2024-2025, a total of 45 DWRs are functional at real time- a 3-times increase has been noted.
-  IMD currently is equipped with a Decision Support System (DSS) based real time multi-hazard impact based early warning system (EWS) which integrates all types of real time and historical data, NWP products, etc to effectively Monitor, detect and  provide timely forecasts and  impact based  warnings with suggested actions upto districts and city/station levels against all types of extreme weather events such as heavy rainfall events, floods, droughts etc. IMD has Met Centres (MCs) in each State and also special centers like Cyclone Warning Centers and Flood Meteorological Offices available for each impacted states, which provides services during cyclones and heavy rainfall Seasons round the clock, respectively.
-  Besides a seamless forecast system with implementation of new model products, which  has  helped  improvement  of  real-time  ERF  and  Monthly  and  seasonal forecasts as discussed in (a) , Heavy rainfall warning is currently issued up to 7 days in advance as compared to 5 days in advance during 2014. Nowcasting is currently issued for each district and location/city, in contrast to a few cities and districts in 2014.  Also,  Impact  Based  Forecast  (IBF)  and  risk-based  warning  up  to  district levels have been introduced since 2019.
-  Earlier, till 2014, it was issued at the sub-division level. From 2022, it is issued at the sub-division, District, and station levels, and is updated twice a day.
-  Quantitative  Precipitation  Forecast  (QPF):  Validity  of  QPF  was  for  2  days  and outlook for the subsequent 3 days in 2014. Presently, Validity is for the next 7 days.
-  The Ministry had launched an ambitious and well-resourced research programme on a Mission mode, called the Monsoon Mission. The first phase of the mission was implemented  during  2012-2017,  and  the  second  phase  (2017-25)  is  underway. Through  this  mission,  India  has  also  augmented  its  capability  of  a  HighPerformance  Computing  (HPC)  system  for  supporting  meteorological  services, which is close to 22 petaflops capacity now, and it is the backbone of the monsoon research  and  operational  services  in  the  country.  India  has  the  fourth-best computing facilities in the world for weather and climate services.
- (e) IMD is  one  of  the  founder  members  of  the  World  Meteorological  Organisation (WMO) and supports various countries through exchange of observations, model guidance,  weather  &  climate  forecast,  knowledge  sharing,  and  capacity  building initiatives. Various weather and climate services provided by IMD to South Asian Countries  including  Afghanistan,  Bangladesh,  Bhutan,  India,  Maldives,  Nepal, Pakistan, and Sri Lanka are given below: IMD acts as one among the five Regional Specialised  Meteorological  Centres  (RSMC) established  as  part  of  the  WMO Tropical Cyclone Programme (TCP) for promoting and coordinating the planning and implementation of measures to mitigate tropical cyclone disasters in respective region. As RSMC, IMD provides daily guidance for cyclonic disturbances over the North Indian Ocean, weekly extended range outlook and 3 hourly bulletins during cyclones. It acts among 6 Tropical Cyclone Advisory Centre (TCAC) globally to provide cyclone advisories to Asia Pacific countries and Middle East countries for civil aviation as per International Civil Aviation Organisation guidelines.

IMD is also leading WMO's Severe Weather Forecasting Project (SWFP) - South Asia. It provides daily severe weather guidance on heavy rainfall, strong wind, storm surge,  high  waves,  and  cyclonic  disturbances  to  9  member  countries,  including Thailand, Myanmar, Bangladesh, Nepal, Bhutan, India, Sri Lanka, Maldives, and Pakistan,  through  a  dedicated  webpage  and  email.  It  also  provides  training  to Forecasters of member countries. IMD is also leading WMO's Advisory Group on Severe  Weather  Forecasting.  It  also  acts  as  South  Asia  Flash  Flood  Guidance WMO's Regional Centre for Flash Flood Guidance at sub catchment scale over the South Asian region (Nepal, Bhutan, Bangladesh, Sri Lanka & India) with focus on hilly regions, steep terrains and urban centres. It provides guidance on impact-based flood warning, urban flood warning, riverine/channel routing, etc. IMD, Pune office currently has been acting as one of the 7 WMO's Regional Climate Centres and is involved  in  providing  Long  Range  Forecast  (LRF),  climate  monitoring,  data services, and training to support regional and national climate services. India acts as the RCC for the Third Pole region.

## Monthly and Homogenous-wise Forecasts of Southwest Monsoon 2025:

The monthly monsoon rainfall for the country as a whole was predicted to be >108% of Long Period Average (LPA) for June, >106 % of LPA for July, 94 to 106 % of LPA for August, and >109 % of LPA for September. The realised monthly rainfall over the country as a whole was 109% of LPA in June, 105% in both July and August, and 115% of LPA in September. Hence, the monthly rainfall forecasts were accurate for the southwest monsoon of 2025.

The southwest monsoon seasonal (June to September 2025) rainfall was forecasted to be abovenormal over Central India and South Peninsular India (>106% of LPA), above normal over Northwest India (>108% of LPA), and below normal over Northeast India (<94% of LPA). The southwest monsoon seasonal rainfall over the monsoon core zone, consisting of most of the rainfed agriculture areas in the country, was most likely to be above Normal (>106% of LPA).  The  observed  rainfall  over  Northwest  India,  Central  India,  Northeast  India,  South Peninsula,  and  Monsoon  Core  Zone  were  27%,  15%,  -20%,  10%  and  22%  of  the  LPA, respectively. The seasonal forecast issued for homogeneous regions during the season  was within the range of the forecast, except for Northwest India.

Annexure-2

| YEAR                       | All India Monsoon Rainfall (LPA)   | All India Monsoon Rainfall (LPA)   | All India Monsoon Rainfall (LPA)   |
|----------------------------|------------------------------------|------------------------------------|------------------------------------|
| YEAR                       | Actual (%)                         | Forecast (%)                       | Remark                             |
| 2021                       | 100                                | 101                                | Accurate                           |
| 2022                       | 106                                | 103                                | Accurate                           |
| 2023                       | 95                                 | 96                                 | Accurate                           |
| 2024                       | 108                                | 106                                | Accurate                           |
| 2025                       | 108                                | 106                                | Accurate                           |
| ***Model error ± 4% of LPA | ***Model error ± 4% of LPA         | ***Model error ± 4% of LPA         | ***Model error ± 4% of LPA         |