1. The South American Monsoon System: Recent Evolution and Current Status Update prepared by Climate Prediction Center / NCEP 2 November 2015 For more information, visit: http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/American_Monsoons http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/American_Monsoons

2. Outline Highlights Recent Evolution and Current Conditions NCEP/GFS Model Forecasts Climatology

3. Rainfall deficits continue over many areas of northern South America, including the Brazilian Plateau. During the last 7 days (26 October -1 November 2015), below-average precipitation was observed over most of northwestern South America, and portions of southeastern and southern Brazil. Above-average precipitation was observed over northern Argentina, central and southern Paraguay and scattered portions of central Brazil. For 2-8 November 2015, above-average rainfall is predicted for portions of Venezuela, Colombia, Ecuador, Peru, Paraguay and southern Brazil (20-30S). Below-average rainfall is predicted for portions of central and eastern Brazil (5-20S), and eastern Argentina. Highlights

4. Rainfall Total & Anomaly Patterns: Last 7 Days During the last 7 days, below-average precipitation was observed over most of northwestern South America, and portions of southeastern and southern Brazil. Above-average precipitation was observed over northern Argentina, central and southern Paraguay and scattered portions of central Brazil. TotalAnomaly

5. Rainfall Totals & Anomaly Patterns: Last 30 Days During the last 30 days, below-average precipitation was observed over most of northern South America, and northern, central and southeastern Brazil. Above-average precipitation was observed over central Paraguay, northern Uruguay and portions of southern Brazil. TotalAnomaly

6. BP Recent Evolution: Rainfall Last 90 Days BP: Brazilian Plateau 90-day rainfall deficits are present over the southern Amazon Basin (~220 mm) and the Brazilian Plateau (~70-110mm). 90-day rainfall is slightly below average (~50 mm) over southern Brazil.

7. Tropical Pacific and Atlantic SST Anomalies A weekly PowerPoint summarizing the ENSO Cycle: Recent Evolution, Current Status and Predictions is available at: http://www.cpc.noaa.gov/products/precip/CWlink/MJO/enso.shtml SSTs are above average in the equatorial Pacific, and near or slightly above average in the equatorial Atlantic. (For details concerning El Niño – La Niña, go to the link below.)

8. Atmospheric Circulation Recent 7 days Upper panels: During the period of 24-30 October 2015, anomalous anticyclonic flow (center indicated by red A) dominated southeastern South America. Lower panels: Anomalous rising motion was observed over southern Bolivia, Paraguay, and northern and central Argentina. Anomalous sinking motion occurred over the central and eastern Amazon Basin. Rising motion (negative omega, yellow/red shading), usually associated with wetter- than- normal conditions. Sinking motion (positive omega, blue shading), usually associated with drier-than-normal conditions. A

9. 925-hPa Wind &Temperature Recent 30 DaysRecent 7 Days Low-level (~600 m above sea level) wind and temperature anomalies based on the NCEP Climate Data Assimilation Systems (CDAS) analysis. The patterns of anomalous temperature and wind at 925-hPa are usually similar to surface observations. Note: Areas with surface pressure below 925-hPa are masked out. During the 7-day period 24-30 October 2015, above-average temperatures were observed over northern and central Brazil. Below-average temperatures were observed over Uruguay and eastern Argentina.

10. NCEP/GFS Model Forecasts Bias-Corrected Precipitation Total Forecasts from 2 November 2015 – Days 1-7 Anomaly Note: Bias correction based on last 30-day forecast error.

11. NCEP/GFS Model Forecasts Bias-Corrected Precipitation Total Forecasts from 2 November 2015 – Days 8-14 Anomaly Note: Bias correction based on last 30-day forecast error.

12. For Days 1-7 (2-8 November 2015), above-average rainfall is predicted for portions of Venezuela, Colombia, Ecuador, Peru, Paraguay and southern Brazil (20-30S). Below-average rainfall is predicted for portions of central and eastern Brazil (5-20S), and eastern Argentina. For Days 8-14 (9-15 November 2015), above-average precipitation is predicted for portions of Venezuela, Colombia, Ecuador, southern Peru, Paraguay and southern Brazil. Below-average precipitation is predicted for Brazil from 5S to 20S. NCEP/GFS MODEL FORECASTS

13. Forecast Verification Forecast from 19 Oct. 2015 Valid for 26 Oct.-1 Nov. 2015 Forecast from 26 Oct. 2015 Valid for 26 Oct.-1 Nov. 2015 Observed 26 Oct.-1 Nov. 2015

14. Climatology Rainy Season Dates ONSETDEMISE

15. Precipitation Climatology

16. Precipitation Climatology Animation