1、The South American Monsoon System: Recent Evolution and Current Status,Update prepared by Climate Prediction Center / NCEP 01 October 2018,For more information, visit: http:/www.cpc.ncep.noaa.gov/products/Global_Monsoons/American_Monsoons,Outline,HighlightsRecent Evolution and Current ConditionsNCEP
2、/GFS Model ForecastsClimatology,Long-term rainfall deficits are present over the Amazon Basin, the Brazilian Plateau and the extreme southern Brazil. During the last 7 days, below-average precipitation was observed over portions of northwestern, west-central and southern Brazil, as well as northern
3、Peru. Above-average precipitation was observed over portions of the extreme southern Brazil, northern Bolivia, southern Paraguay, Uruguay and eastern Argentina. For Days 1-7 (01 07 October 2018), below-average precipitation is predicted for portions of west-central Colombia, southern and eastern Ven
4、ezuela, northern and central Brazil, central-east Argentina and southern Chile. Above-average precipitation is predicted for portions of the extreme southern Brazil, northern and southern Colombia, northern Peru and southern Paraguay.,Highlights,Rainfall Total & Anomaly Patterns: Last 7 Days,During
5、the last 7 days, below-average precipitation was observed over portions of northwestern, west-central and southern Brazil, as well as northern Peru. Above-average precipitation was observed over portions of the extreme southern Brazil, northern Bolivia, southern Paraguay, Uruguay and eastern Argenti
6、na.,Total,Anomaly,Rainfall Totals & Anomaly Patterns: Last 30 Days,During the last 30 days, below-average precipitation was observed over portions of the northern Colombia, southern Venezuela, central and northern Brazil, and northern Peru. Above-average precipitation was observed over portions of e
7、astern Colombia, southern Paraguay, Uruguay and the extreme southern Brazil.,Total,Anomaly,Recent Evolution: Rainfall Last 90 Days,BP: Brazilian Plateau,90-day rainfall deficits are present over the Amazon Basin ( 50 mm) , the Brazilian Plateau ( 20 mm) and the extreme southern Brazil ( 50 mm).,Trop
8、ical 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 across the tropical Pacific, north of the Equator. (For detail
9、s concerning El Nio La Nia, go to the link below.),Atmospheric Circulation Recent 7 days,Upper panels: During the period of 23 -29 Sept 2018, anomalous anticyclonic flow (center noted by red A) was observed off the southeast coast of Brazil.Lower panels: Anomalous sinking motion was observed over mu
10、ch of northern Brazil and northern Chile. Anomalous rising motion was observed over southern Brazil, southern Chile and southern Argentina.,Rising motion (negative omega, yellow/red shading), usually associated with wetter- than-normal conditions. Sinking motion (positive omega, blue shading), usual
11、ly associated with drier-than-normal conditions.,A,925-hPa Wind &Temperature,Recent 30 Days,Recent 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 ar
12、e usually similar to surface observations. Note: Areas with surface pressure below 925-hPa are masked out.,During the 7-day period 23 29 Sept 2018, above-average temperature was observed over much of Brazil and eastern Argentina.,NCEP/GFS Model Forecasts Bias-Corrected Precipitation,Total,Forecasts
13、from 01 October 2018 Days 1-7,Anomaly,Note: Bias correction based on last 30-day forecast error.,NCEP/GFS Model Forecasts Bias-Corrected Precipitation,Total,Forecasts from 01 October 2018 Days 8-14,Anomaly,Note: Bias correction based on last 30-day forecast error.,For Days 1-7 (01 07 October 2018),
14、below-average precipitation is predicted for portions of west-central Colombia, southern and eastern Venezuela, northern and central Brazil, central-east Argentina and southern Chile. Above-average precipitation is predicted for portions of the extreme southern Brazil, northern and southern Colombia
15、, northern Peru and southern Paraguay. For Days 8-14 (08-14 Oct 2018), below-average precipitation is predicted over portions of northern Brazil, northern Colombia, eastern Venezuela and southern Chile. Above-average precipitation is predicted for southern Brazil, southern Paraguay and central Peru.,NCEP/GFS MODEL FORECASTS,Climatology Rainy Season Dates,ONSET,DEMISE,Precipitation Climatology,Precipitation Climatology Animation,
