1. for the 2017 NE Monsoon Season
Consensus Forecast
for the 2017 NE Monsoon Season
D. S. Pai
RCC, Pune

2. Verification of Last 2016 Forecast Outlook: OND 2016 & DJF 2016-17
Normal rainfall is most likely over most parts of south Asia during the 2016 Northeast monsoon season (October – December). However, below normal rainfall is likely over some areas of southeast peninsular India, Sri Lanka and Maldives. Below normal rainfall is also likely over some areas of north and eastern parts of the region. Above normal rainfall is likely over western and northwestern parts of Pakistan and some northeastern parts of the region.
During the season, normal to slightly above normal temperatures are likely, over most parts of the region.
Below normal precipitation is likely during the Winter Season (December 2016 to February 2017) over northern most parts of the south Asia, Maldives & neighboring Lakshadweep, and northeastern parts of South Asia including northeast India, east Nepal, Bhutan, and northern parts of Myanmar. Normal precipitation is likely over the remaining parts of the region.
During the season, normal to above normal temperatures are likely, over most parts of the region.

3. ENSO & IOD: Status and Forecast

4. ENSO Status : CPC
Equatorial SSTs were above average in the central Atlantic, the western Indian, and in the far western Pacific Oceans. SSTs were below average in the central and eastern Pacific

5. MMCFS Forecast (Nino 3.4) Plume Forecast: SST anom PDF Corrected
Probability Forecast
The current ENSO neutral conditions over equatorial Pacific likely turn to cool neutral conditions during the OND season and then to weak La Nina conditions by early next year.

6. IRI/CPC Pacific Niño 3.4 SST Model Outlook
Although SSTs in the east-central tropical Pacific have cooled to the threshold for La Niña, the atmosphere continues to maintain largely ENSO-neutral patterns. The collection of latest ENSO prediction models indicates coolish ENSO-neutral or weak La Niña as two possible scenarios during Northern Hemisphere fall and winter.

7. Bureau Of Meteorology (POAMA & Other Models)
Published on 10th September 2017

8. IOD Condition

9. MMCFS Forecast (IOD) Probability Forecast
Plume Forecast: SST anom PDF Corrected
Probability Forecast
The current IOD neutral conditions over equatorial Pacific likely continue during the OND season and thereafter

10. IOD: Bureau Of Meteorology (POAMA & Other Models)

11. Summary of Status and Outlook of ENSO & IOD
Currently, ENSO neutral conditions are prevailing with Nino3.4 values close to normal values. Atmospheric conditions over the Pacific also indicate ENSO neutral conditions. The latest MMCFS forecast indicates high probability for cooling of SSTs over equatorial central and east Pacific leading to cool ENSO neutral conditions during the 2017 NE monsoon season and then turning to weak La Nina conditions in the early part of next year.
Currently, Indian Ocean Dipole (IOD) neutral conditions are prevailing. The latest forecast from the MMCFS indicates IOD neutral conditions to continue during the northeast monsoon season.

12. Forecasts from Country Representatives
Rainfall Forecast
Temp Forecast
AFGANISTAN
NORMAL
NORMAL TO ABOVE NORMAL
BANGLADESH
BHUTAN
Normal
 Normal to above normal
INDIA (South Peninsula)
MALDIVES
 Above Normal over north
Normal over central and south
 Normal to slightly above normal
MYNMAR
NORMAL TO SLIGTHTLY ABOVE NORMAL
OND: Above normal
NEPAL
PAKISTAN
SRILANKA
 NORMAL

13. Consensus Forecast Map
OND Precipitation
OND Temperature
Temperature over most of the region is likely to be normal to slightly above normal

14. Summary
Below normal rainfall is most likely during the 2017 OND Season over some parts of SE Peninsular India, north Sri Lanka and few northeastern areas of the region. Above normal is most likely over some southern areas of the region and along the coastal areas adjacent to the north Bay of Bengal. Over remaining areas of the region including northwest and central areas that generally receive very little rain during the season, rainfall is most likely to be Normal.
Normal to slightly above normal temperatures are likely during the 2017 OND Season over most parts of the region.

15. Currently cool neutral ENSO conditions prevail in the Pacific Ocean and these conditions are likely to continue and turn to border line/ weak La Nina conditions in the early next year. It is also recognized that during the 2017 OND season, in the absence of SST forcings from Pacific and Indian oceans, other regional and global factors as well as the strong intra seasonal features of the region will have larger influence on the climate anomaly patterns over the region leading to increased uncertainty in the prediction of the season averaged rainfall and temperature patterns over the region.
The consensus forecast outlook presented here has been developed through an expert assessment of the prevailing global climate conditions and forecasts from different climate models from around the world.
A separate consensus statement for winter season (December 2017 to February 2018) will be issued in November 2017.

16. Thank you
11/14/2018 16