1. Extended range prediction during 2013 season Using Ensemble Prediction System based in CFSv2 And GFSv2 forced with Bias corrected CFSv2 forecasted SST Working group on Extended Range Prediction Ministry of Earth System Sciences, India INITIAL CONDITION 10 th June 2013

2. Ocean and Atmospheric Initial conditions (IC) are obtained from NCEP. Technique was developed to perturb ICs to generate 11 members. (Abhilash et al., 2013) Model has been integrated for 45 days for each 11 ICs at five day intervals starting from 16 th May (Eg: 16May, 21May, 26May, 31May, 05Jun........etc). Climatology has been calculated from 10-year hindcast. Bias correction in daily forecasted SST from CFSv2 for each lead time has been done by removing the daily mean bias for corresponding lead time (model climatology-observed climatology) from forecasted daily SST. (Sahai et al., 2013; Abhilash et al., 2013) Strategy: Ensemble Prediction using CFS/GFSv2 (T126)

3. FORECAST FROM CFSv2(T126) And Bias Corrected GFSv2(T126) Based on IC 10 th June 2013

4. Daily evolution of rainfall and wind at 850hPa CFS forecast based on IC=10 June 2013

5. Daily evolution of rainfall and wind at 850hPa GFS forecast forced with bias corrected CFS forecasted SST based on IC=10 June 2013

6. Daily evolution of vorticity at 850hPa CFS forecast based on IC=10 June 2013

7. Daily evolution of vorticity at 850hPa GFS forecast forced with bias corrected CFS forecasted SST based on IC=10 June 2013

8. CFS forecast based on IC=10 June 2013 Actual Anomaly

9. GFSbc forecast based on IC=10 June 2013 Actual Anomaly

10. CFS-GFS Forecast Over Homogenous Regions MZI, CEI, NEI, NWI & SPI

11. CFS

12. GFSbc

13. MISO monitoring and forecast for next 25 days CFS GFSbc

14. Inferences from the present analysis Both CFSv2 and GFSbc show that rainfall over monsoon zone of India (MZI) would start to intensify from 13 th Jun onwards. This intensification of rainfall is likely due to the formation of a system over BOB. Monsoon trough would be over MZI around 13 th Jun both in CFSv2 and GFSbc. CFSv2 indicates more rainfall over main land of India during P1(11-15June), P2(16-20 Jun) and P4(26-30 Jun); while less rainfall is predicted during P3(21- 25Jun). Positive anomalies are seen over west coast and MZI during P1(11-15June), P2(16-20 Jun) and P4(26-30 Jun). GFSbc indicates not much difference during P1. But the rainfaal pattern in P2-P4 are different from that of CFSv2.

15. CFSv2 shows the above normal condition over MZI (during P1-P4), CEI (during P1, P2 and P4), NWI (during P2 and P3) and SPI (during P1, P2 and P4). Near normal conditions are seen over CEI (during P3), NEI (during P1-P3), NWI (during P4). Below normal conditions are seen over NEI (during P4), NWI (during P1) and SPI (during P3). GFSbc shows the above normal condition over MZI (during P1 and P2), CEI (during P1, P2 and P4), NWI (during P2 and P4) and SPI (during P1 and P3). Near normal conditions are seen over MZI (during P3 and P4), CEI (during P3), NEI (during P1-P4) and NWI (during P3). Below normal conditions are seen over NWI (during P1) and SPI (during P2 and P4). Inferences from the present analysis

16. Real time forecast for MISO shows a prominent northward propagation from both CFSv2 and GFSbc. However GFSbc shows faster propagation than that in CFSv2. Inferences from the present analysis

17. Verification

18. Forecast of Monsoon Onset over Kerala Based on 16 May 2013: 29 May 2013 Onset date forecasts are obtained from each 11 member of CFSv2 45 day forecast. Then ensemble mean is given as the final forecasted onset date. Y axis on each panel is in mm/day for rainfall (bars) and m/s for 850hPa wind(green line). Red circle is the onset date and also written at the top of each panel Onset declared by IMD: 1 st June 2013

19. NCEP/TRMM Analysis Wind (850hPa) and R/F Verification CFSv2 GFSbc F/C from 16May IC F/C from 16May IC

20. NCEP/TRMM Analysis Wind (850hPa) and R/F Verification CFSv2 GFSbc F/C from 26May IC F/C from 26May IC

21. CFS-GFS Verification Over Homogenous Regions MZI, CEI, NEI, NWI & SPI

22. CFS, CEI

23. GFSbc, CEI

24. CFS, MZI

25. GFSbc, MZI

26. CFS, NEI

27. GFSbc, NEI

28. CFS, NWI

29. GFSbc, NWI

30. CFS, SPI

31. GFSbc, SPI

32. 16 May IC21 May IC MISO F/C verification (OBS is for 20 days only)

33. MISO F/C verification 26 May IC (OBS is for 15 days only)