722  
FXSA20 KWBC 141403  
PMDSA  
 
SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
903 AM EST TUE NOV 14 2017  
 
GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/  
 
SYNOPSIS (VALID FROM NOV 14 AT 0000 UTC): THE 200 HPA ANALYSIS  
SHOWS BROAD CELL OF THE SUBTROPICAL RIDGE GRADUALLY BECOMING  
DOMINANT FEATURE OVER THE CONTINENT WHILE CENTERING ON A CLOSED  
HIGH OVER NORTHWEST BRASIL NEAR 09S 62W. THE RIDGE ALOFT IS  
VENTING DEEP CONVECTION ALONG A LINE THAT EXTENDS EAST-TO-WEST  
FROM BAHIA TO AMAZONAS IN BRASIL/NORTHERN JUNGLE OF PERU-SOUTHERN  
COLOMBIA.  
 
AT 250 HPA...THE SOUTHERN POLAR HAS A FINGER THAT EXTENDS BETWEEN  
54S 54W AND 44S 46W. THE NORTHERN POLAR HAS ITS ENTRANCE AT 30S  
99W...THEN ALONG 33S 89W...39S 81W...A 123KT MAXIMUM AT 45S  
72W...47S 62W...43S 53W...A 139KT MAXIMUM AT 39S 48W...35S  
42W...EXITING AT 34S 38W. THE SUBTROPICAL JET HAS ITS ENTRANCE AT  
25S 117W...THEN ALONG 24S 108W...26S 99W...30S 87W...36S 77W...41S  
62W...35S 47W...28S 40W...EXITING AT 26S 36W. A FINGER TO THE  
NORTH EXTENDS BETWEEN 25S 58W AND 18S 51W. THE JET REFORMS AT 20S  
38W...THEN ALONG 23S 32W...28S 27W...A 154KT MAXIMUM AT 36S  
23W...42S 13W...AND A 170KT MAXIMUM AT 39S 00W. THE SUBEQUATORIAL  
JET LIES ALONG 15S 120W...11S 110W...EXITING AT 06S 101W.  
 
AT 500 HPA...A SKEWED TROUGH OVER THE FAR EASTERN PACIFIC  
STRETCHES FROM TIERRA DEL FUEGO/SOUTHERN CHILE...ALONG 40S  
90W...TO 30S 94W. THIS IS FOCUSING SHORT WAVE ENERGY ACROSS  
SOUTHERN PATAGONIA IN ARGENTINA WHILE PRESSING AGAINST A RIDGE TO  
THE EAST. THE RIDGE EXTENDS NORTH-TO-SOUTH ALONG 62W/65W TO THE  
DRAKE PASSAGE/ANTARCTIC PENINSULA. EAST OF THIS RIDGE...SHORT WAVE  
TROUGH ON THE SOUTHERN STREAM EXTENDS NORTH ACROSS THE SOUTH  
GEORGIA ISLANDS TO 48S 45W. THIS IS PHASING WITH A SHORT WAVE  
TROUGH TO THE NORTH THAT EXTENDS BETWEEN 50W-20W AND TO THE SOUTH  
OF 20S.  
 
AT LOW LEVELS...BROAD RIDGE ON THE NORTHERN STREAM DOMINATES THE  
SOUTH PACIFIC WHILE CENTERING ON A 1029 HPA HIGH AT 36S 118W. EAST  
OF THIS AXIS...AN ELONGATED FRONT EXTENDS FROM AN OCCLUDED 996 HPA  
LOW AT 50S 76W...ALONG A 994 HPA LOW AT 50S 68W...45S 66W...40S  
67W...35S 75W...A 1018 HPA LOW AT 33S 84W...26S 89W...22S  
96W...AND 20S 102W. THIS FAVORS LIGHT RAINFALL ACROSS SOUTHERN  
PATAGONIA IN ARGENTINA. OVER THE ATLANTIC...A FRONT EXTENDS FROM A  
990 HPA LOW AT 42S 38W...THEN ALONG A 986 HPA LOW AT 44S 37W...39S  
33W...33S 40W...RIO GRANDE DO SUL TO ENTRE RIOS IN ARGENTINA. A  
POLAR RIDGE TO THE SOUTH CENTERS ON A 1017 HPA HIGH AT 38S 55W.  
ANOTHER FRONT TO THE EAST AND NORTH EXTENDS ALONG A 1000 HPA LOW  
AT 42S 21W...38S 19W...A 1002 HPA LOW AT 36S 20W...28S 22W...20S  
28W...17S 34W...ESPIRITO SANTO...SAO PAULO TO SOUTHEAST PARAGUAY.  
CONVECTION IS CLUSTERING TO THE NORTH OVER BAHIA-TOCANTINS/GOIAS.  
 
OVIEDO...SHN (ARGENTINA)  
VANNUCCI...SMN (ARGENTINA)  
RIVAS...SENAMHI (PERU)  
DAVISON...WPC (USA)  

 
 
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