SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
826 AM EDT THU JUN 13 2013

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

SYNOPSIS (VALID FROM 00 UTC JUNE 13): AT UPPER LEVELS...THE 200
HPA ANALYSIS SHOWS A CLOSED RIDGE OVER WESTERN BRASIL CENTERING ON
A HIGH NEAR 05S 64W. AN INDUCED TROUGH TO THE EAST EXTENDS NORTH
ALONG 47W/48W TO THE NORTHERN COAST OF BRASIL. IN THIS
PATTERN...TROPICAL CONVECTION CONFINES TO AREA NORTH OF 03S...WITH
MOST ACTIVE ACROSS THE GUIANAS TO VENEZUELA-COLOMBIA.
OTHERWISE...WIDELY ISOLATED CONVECTION WAS DOTTING THE
SIERRA/JUNGLE OF PERU AND PORTIONS OF BOLIVIA.

AT 250 HPA...THE JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH AXIS
ALONG 60S 120W...A 126KT MAXIMA AT 60S 110W...58S 91W...52S
84W...EXITING AT 48S 61W. IT REFORMS AT 48S 52W...ALONG 48S
42W...51S 33W...EXITING AT 51S 16W. THE NORTHERN POLAR LIES ALONG
34S 120W...36S 110W...A 120KT MAXIMUM AT 43S 100W...A 151KT
MAXIMUM AT 47S 90W...A 175KT MAXIMUM AT 46S 80W...41S 63W...42S
44W...47S 26W...AND 44S 10W. THE SUBTROPICAL JET HAS ITS ENTRANCE
AT 18S 80W...ALONG 18S 72W...21S 62W...EXITING AT 20S 51W. THE JET
REFORMS AT 26S 48W...ALONG 28S 30W...EXITING AT 30S 07W.

AT 500 HPA...STRONG SHORT WAVE TROUGH ON THE SOUTHERN STREAM
ENTERED THE DRAKE PASSAGE/SOUTHERN CONE...WITH SHORT WAVE ENERGY
FOCUSING ACROSS TIERRA DEL FUEGO/EXTREME SOUTHERN PORTIONS OF
CHILE. A SHORT WAVE TROUGH ON THE NORTHERN STREAM FOLLOWS...WITH
AXIS NORTHWEST ALONG 47S 100W TO 34S 115W. ALSO ON THE NORTHERN
STREAM...A CLOSED LOW NEAR 24S 78W ANCHORS A SHORT WAVE TROUGH OFF
THE NORTHERN COAST OF CHILE. FARTHER EAST...OVER THE SOUTH
ATLANTIC...A TROUGH IS PULLING ACROSS 44W WHILE CONFINING TO SOUTH
OF 40S.

SURFACE ANALYSIS SHOWS A RIDGE ON THE NORTHERN STREAM OVER THE FAR
EASTERN PACIFIC THAT CENTERS ON A 1025 HPA HIGH AT 31S 91W. A
POLAR FRONT ON THE SOUTHERN STREAM ENTERED THE SOUTHERN CONE...AS
IT EXTENDS FROM AN OCCLUDED 978 HPA LOW AT 59S 73W...ALONG 60S
71W...A 986 HPA LOW AT 56S 66W...50S 64W...47S 67W...49S 73W...A
998 HPA LOW AT 53S 78W...48S 80W...TO 49S 87W. AN ELONGATED FRONT
DOMINATES THE NORTHERN STREAM FLOW AS IT EXTENDS ALONG A 982 HPA
LOW AT 52S 32W...43S 36W...38S 45W...A 1010 HPA LOW AT 42S
51W...SOUTHERN  BUENOS AIRES-SOUTHERN CUYO...39S 77W...40S
83W...TO A 1016 HPA LOW AT 42S 90W. THESE SUSTAINS SCATTERED
RAINFALL ACROSS THE SOUTHERN CONE...WITH SNOWFALL ON THE SOUTHERN
ANDES OF CHILE.

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