1. Consolidated Seasonal Rainfall Guidance for Global Tropics, December 2015 Initial Conditions Issued 14 December 2015 Forecast Background – ENSO update – Current State of the global climate – SST Forecasts Regional Rainfall Forecast maps Summary

2. CPC ENSO Update CPC ENSO Alert System Status: El Niño Advisory Synopsis: El Niño is expected to remain strong through the Northern Hemisphere winter 2015 - 16, with a transition to ENSO – neutral anticipated during late spring or early summer 2016. (Updated on December 10, 2015) http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ind ex.shtml

3. Tropical SSTs were above average across the central and eastern Pacific. Current State of the Global Ocean SST Anomaly (top) for November 2015 and Tendency (bottom) for November 2015 minus October 2015 Positive SST anomalies were observed across much of the Indian Ocean. SSTs were below average near Indonesia. Changes in equatorial SST anomalies were positive across western and central Pacific, whereas negative SST tendencies were observed across the eastern end of the Pacific Ocean. Last Month SST tendency was negative over many parts of the Indian Ocean.

4. Equatorial SSTs were above average across the central and eastern Pacific. Positive SST anomalies were present over much of the Indian Ocean. Weekly SST Anomaly 6 – 12 December 2015 and Tendency for 6 – 12 December 2015 minus 29 November – 5 December 2015 Last Week Changes in equatorial SST anomalies were positive over much of the Indian Ocean. Current State of the Global Ocean Positive tendencies in SST anomalies were present across much of the Atlantic Ocean.

5. Nino region SST departures Eq. Subsurface temperature Anomalies Niño 40.9ºC Niño 3 0.9ºC Niño 1+2 0.5ºC The latest weekly SST departures : Niño 4 = 1.7ºC Niño 3.4 = 2.8ºC Niño 3 = 2.9ºC Niño 1+2 = 2.3ºC During the last two months, positive subsurface temperature anomalies were observed across the central and eastern equatorial Pacific.

6. OLR Anomaly, November 2015 Negative OLR anomalies (enhanced convection and precipitation, blue shading) was observed across the tropical Pacific Ocean. Precipitation was also higher than average over portions of East Africa, and the central parts of South America. Precipitation was suppressed (orange-red shading) over the Maritime Continent and the western pacific, and northern South America. Precipitation was also lower than average across parts of Southern Africa.

7. Low Level 850 mb Wind Anomaly Anomalous low-level (850-hPa) westerly winds extended from the western to the east-central equatorial Pacific. Anomalous easterly winds persisted in the equatorial Indian Ocean.

8. Upper Level 200 mb Wind Anomaly Anomalous upper-level (200-hPa) easterlies persisted in the equatorial central Pacific.

9. Evolution of Indian Ocean SST Indices The Indian Ocean Dipole (IOD) index has decreased recently. The latest weekly index, as of 13 December 2015, is 0.09°C.

10. Summary of State of the Global Climate in November 2015 El Niño conditions are present. The most recent Ocean Nino Index (ONI) value (September – November 2015) is 2.0 o C. Positive sea surface temperature (SST) anomalies continued across the equatorial central and eastern Pacific. Above-average SSTs were observed across much of the Indian Ocean. The Indian Ocean Dipole (IOD) index remained above- average in November and early December. Enhanced precipitation was observed across the tropical Pacific Ocean. Precipitation was also higher than average over portions of East Africa, and the central parts of South America. Precipitation was suppressed over the Maritime Continent and the western pacific, and northern South America. Precipitation was also lower than average across parts of Southern Africa.

11. -Most models indicate that Niño 3.4 will remain strong into early 2016. -Positive anomalies are predicted to weaken through the Northern Hemisphere Spring 2016. IRI/CPC NINO3.4 Forecast Plume SeasonLa NiñaNeutralEl Niño NDJ 2015~0% 100% DJF 2016~0% 100% JFM 2016~0%1%99% FMA 20161%5%94% MAM 20161%14%85% AMJ 20165%35%60% MJJ 201613%48%39% JJA 201621%53%26% JAS 201631%49%20%

12. Global SST Outlook: NCEP CFS.v2 Forecast Initial Conditions: 3 – 12 December, 2015 Jan - Mar 2016 Mar - May 2016 May - Jul 2016 Feb - Apr 2016 Caution: Ocean areas with skill less than 0.3 are shaded in gray Apr - Jun 2016 CFS.v2 predicts higher than normal SST across equatorial central and eastern Pacific Ocean, and the Indian Ocean. Additional forecast resources are found here: http://www.cpc.ncep.noaa.gov/products/CFSv2/htmls/glbSSTe3SeaMask.html

13. NMME Global SST Outlook (December 2015 Initial Conditions) Jan - Mar 2016Feb - Apr 2016 NMME models predict higher than normal SST across the equatorial central and eastern Pacific, and the Indian Ocean. Mar - May 2016 Apr - Jun 2016

14. IOD Outlook (source: Australian Bureau of Meteorology) Two out of five models suggest that the IOD index will remain above the positive IOD threshold until December.

15. Rainfall Guidance, Africa: NMME, Precipitation Probability Forecasts, ( 01 – 08 December 2015 IC ) Jan – Mar 2016Feb – Apr 2016 Mar – May 2016Apr – Jun 2016 The forecasts call for a moderate tilt in the odds to favor above-average rainfall over portions of East Africa during the northern hemisphere winter and early spring. In contrast, there is a moderate tilt in the odds to favor below-average rainfall along the Gulf of Guinea coast, and portions of Equatorial and Southern Africa. Individual model forecasts can be found here: http://www.cpc.ncep.noaa.gov/products/i nternational/nmme/nmme1.shtml Gray shade indicates indicate dry climatological mask

16. Rainfall Guidance, Maritime Continent: NMME, Precipitation Probability Forecasts, ( 01 – 08 December 2015 IC ) The forecasts call for a slight to moderate tilt in the odds to favor below- average rainfall over portions of Malaysia, and the Philippines. In contrast, there is a light to moderate tilt in the odds to favor above-average rainfall over portions of Indonesia, northern Papa New Guinea, and portions of Australia. Individual model forecasts can be found here: http://www.cpc.ncep.noaa.gov/products/i nternational/nmme/nmme1.shtml Gray shade indicates indicate dry climatological mask Jan – Mar 2016Feb – Apr 2016 Mar – May 2016Apr – Jun 2016

17. Rainfall Guidance, CAM and Caribbean: NMME, Precipitation Probability Forecasts, ( 01 – 08 December 2015 IC ) The forecasts call for a slight to moderate tilt in the odds to favor below- average rainfall over portions of Central America. In contrast, there is a slight tilt in odds to favor above-average rainfall over portions of the Caribbean. Individual model forecasts can be found here: http://www.cpc.ncep.noaa.gov/products/i nternational/nmme/nmme1.shtml Gray shade indicates indicate dry climatological mask Jan – Mar 2016Feb – Apr 2016 Mar – May 2016Apr – Jun 2016

18. Rainfall Guidance, South America: NMME, Precipitation Probability Forecasts, ( 01 – 08 December 2015 IC ) The forecasts call for a moderate tilt in the odds to favor below average rainfall over much of Brazil the neighboring areas. In contrast, there is a slight tilt in the odds to favor above- average rainfall over the central and northwestern parts of South America. Individual model forecasts can be found here: http://www.cpc.ncep.noaa.gov/products/i nternational/nmme/nmme1.shtml Gray shade indicates indicate dry climatological mask Jan – Mar 2016Feb – Apr 2016 Mar – May 2016Apr – Jun 2016

19. Rainfall Guidance, Central Asia: Precipitation Probability Forecasts, ( 01 – 08 December 2015 IC ) The forecasts call for a slight to moderate tilt in the odds to favor above average rainfall over portions of Central Asia. Individual model forecasts can be found here: http://www.cpc.ncep.noaa.gov/products/i nternational/nmme/nmme1.shtml Gray shade indicates indicate dry climatological mask Jan – Mar 2016Feb – Apr 2016 Mar – May 2016Apr – Jun 2016

20. Summary El Niño conditions are present. Above-average Sea surface temperatures (SST) was observed over the central and eastern Pacific Ocean. Positive SST anomalies were observed over much of the Indian Ocean. El Niño is expected to remain strong through the Northern Hemisphere winter 2015 - 16, with a transition to ENSO – neutral anticipated during late spring or early summer 2016. There is a slight to moderate tilt in the odds to favor above average rainfall over portions of East Africa, and central Asia. In contrast, there is a moderate tilt in the odds to favor below-average rainfall over Southern Africa, portions of the Maritime continent and much of Brazil. Additional forecast resources can be found here: http://www.cpc.ncep.noaa.gov/products/african_desk/cpc_intl/index.shtml http://www.cpc.ncep.noaa.gov/products/NMME/ http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/