SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
839 AM EDT FRI JUN 07 2013

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

SYNOPSIS (VALID FROM 00 UTC JUNE 07): A BUILDING UPPER LEVEL RIDGE
IS INITIALIZED ACROSS PERU TO WESTERN BRASIL. THIS IS INDUCING THE
NORTHWARD AMPLIFICATION OF A TROUGH ACROSS PARA TO AMAPA. THE
AMPLIFYING TROUGH FAVORS SCATTERED DEEP CONVECTION. OTHER ACTIVITY
TO THE WEST IS BUILDING ALONG THE JUNGLE OF PERU TO THE SOUTHERN
SIERRA AND THE ALTIPLANO OF BOLIVIA. STRONG SUBSIDENCE CAP ACROSS
SOUTHERN AND SOUTHEAST BRASIL CONTINUE TO INHIBIT DEEP CONVECTION
ACROSS MID SECTIONS OF SOUTH AMERICA.

JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH AXIS ALONG 54S
120W...55S 95W...A 134KT MAXIMUM AT 53S 90W...46S 80W...A 151KT
MAXIMUM AT 46S 72W...47S 65W...EXITING AT 52S 57W. THE NORTHERN
POLAR HAS ITS ENTRANCE AT 39S 91W...ALONG A 153KT MAXIMUM AT 41S
80W...A 180KT MAXIMUM AT 42S 70W...41S 59W...EXITING AT 31S 47W.
THE SUBTROPICAL JET HAS ITS ENTRANCE AT 32S 92W...ALONG 37S
80W...36S 61W...EXITING AT 28S 54W. IT HAS A FINGER TO THE NORTH
THAT LIES BETWEEN 15S 88W AND 16S 74W.

AT 500 HPA...A PROGRESSIVE PERTURBATION ON THE SOUTHERN STREAM
ENTERED THE DRAKE PASSAGE/SOUTHERN CHILE...WITH AXIS FOCUSING ITS
SHORT WAVE ENERGY ACROSS CENTRAL AND SOUTHERN PORTIONS OF
PATAGONIA. AN INDUCED RIDGE LIES TO THE EAST...WITH AXIS SOUTHEAST
FROM CENTRAL ARGENTINA...ALONG 40S 60W...50S 50W TO THE SOUTH
GEORGIA ISLANDS. ANOTHER TROUGH LIES TO THE EAST AND NORTH...WITH
AXIS NORTHWEST ALONG 50S 37W...40S 40W...TO RIO GRANDE DO SUL IN
SOUTHERN BRASIL.

SURFACE ANALYSIS SHOWS A TROUGH ON THE SOUTHERN STREAM WITH AXIS
NORTH INTO THE SOUTHERN CONE OF SOUTH AMERICA. POLAR FRONTS EMBED
IN THIS AXIS...WITH ONE THAT EXTENDS ALONG AN OCCLUDED 966 HPA LOW
AT 58S 69W...ALONG 60S 67W...58S 64W...A 970 HPA LOW AT 56S
66W...52S 62W...49S 63W...A 998 HPA LOW AT 47S 66W...TO 43S 71W. A
SECONDARY FRONT FOLLOWS...AS IT EXTENDS ALONG A 984 HPA LOW AT 50S
72W...45S 73W...TO 43S 84W. A THIRD BOUNDARY TO THE EAST AND NORTH
EXTENDS ALONG A 998 HPA LOW AT 49S 61W... NORTHERN
PATAGONIA...TEMUCO CHILE...TO 33S 96W. THESE COMBINE IN SUPPORT OF
SCATTERED CONVECTION OVER SOUTHERN CHILE/SOUTHERN ANDES OF
ARGENTINA. EAST OVER THE ATLANTIC...A FRONT ON THE NORTHERN STREAM
EXTENDS ALONG A 998 HPA LOW AT 45S 29W...41S 32W...40S 34W...A
1004 HPA LOW AT 39S 37W...32S 41W... SOUTHERN SAO PAULO TO
NORTHWEST ARGENTINA. A POLAR RIDGE TO THE SOUTH CENTERS ON TWO
1021 HPA HIGHS...WITH ONE AT 31S 61W AND THE OTHER AT 33S 56W.

OLIVARES...SENAMHI (PERU)
SILVA DE SOUZA...INMET (BRASIL)
DAVISON...WPC (USA)