Skip Navigation Links weather.gov 
NOAA logo - Click to go to the NOAA homepage National Weather Service   NWS logo - Click to go to the NWS homepage
The Weather Prediction Center
 
South American Synoptic Discussion
 
(Caution: Version displayed is not the latest version. - Issued 1405Z Jan 09, 2015)
 
Version Selection
Versions back from latest:  0   1   2   3   4   5   6   7   8   9   10   
 
Abbreviations and acronyms used in this product


SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
905 AM EST FRI JAN 09 2015

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

SYNOPSIS (VALID FROM JANUARY 09 AT 00UTC): THE 200 HPA ANALYSIS
SHOWS THE SUBTROPICAL RIDGE ESTABLISHED FAR TO THE SOUTH-SOUTHEAST
FROM ITS CLIMATOLOGICAL POSITION...CENTERING OVER
PARAGUAY/MISIONES IN ARGENTINA AND ELONGATING FROM SOUTHEASTERN
PERU INTO SANTA CATARINA AND RIO GRANDE DO SUL. THE RIDGE IS
MIGRATING INTO THE SOUTHERN ATLANTIC AIDED BY A WIDESPREAD REGION
OF POSITIVE SEA SURFACE TEMPERATURE ANOMALIES OFF THE COAST OF
SOUTHERN/SOUTHEASTERN BRASIL AND THE RIO DE LA PLATA. TO THE
NORTH...A BROAD CAVADO DO NORDESTE HAS AN ELONGATED CENTER FROM
SOUTHEASTERN PARA INTO MINAS GERAIS. THE CAVADO/TUTT IS
RETROGRESSING TO THE WEST AS THE SUBTROPICAL HIGH TO THE SOUTH IS
DISPLACED TO THE EAST. A PERSISTENT TROUGH PATTERN DOMINATES OVER
THE EASTERN PACIFIC OFF THE COASTS OF NORTHERN CHILE AND SOUTHERN
PERU. THIS IS LEADING TO THE MOST FAVORABLE VENTILATION OVER
SOUTHERN PERU AND THE ALTIPLANO...WHICH HAS BEEN SUSTAINING A
SEASONALLY ACTIVE PATTERN OF DIURNAL CONVECTION. DEEP CONVECTION
IS ALSO BEING VENTILATED ACROSS WESTERN PARA/SOUTHEASTERN AMAZONAS
IN BRASIL...IN THE PERIPHERY OF THE CAVADO DO NORDESTE WHERE THE
TROUGH IS INTERACTING WITH AN UNSTABLE AIRMASS.

AT 250 HPA...THE JET ANALYSIS SHOWS THE SOUTHERN POLAR JET
EXTENDING ALONG A 142KT MAXIMA AT 52S 109W ALONG 51S 94W...EXITING
AT 50S 79W. IT REFORMS AT 54S 61W ALONG A 127KT MAXIMA AT 49S
40W...47S 26W. THE NORTHERN POLAR FORMS AT 43S 91W ALONG 42S
73W...43S 64W...44S 45W...43S 25W...A 169KT MAXIMA AT 43S 14W. THE
SUBTROPICAL JET FORMS AT 27S 69W ALONG 36S 37W...A 136KT MAXIMA AT
37S 40W...38S 25W.

AT 500 HPA AND IN THE SOUTHERN STREAM...VERY  BROAD TROUGH PATTERN
ENCOMPASSES THE SOUTHERN STREAM AS A PLANETARY-SCALE TROUGH
EXTENDS FROM 110W TO 10W AND TO THE SOUTH OF 40. SHORT WAVE
PERTURBATIONS ARE ORGANIZING IN ITS PERIPHERY. ONE EXTENDS ALONG
100W AND ANOTHER ALONG 50W. IN THE NORTHERN STREAM...SHORT WAVE
TROUGH HAS CROSSED THE ANDES AND CENTERS ALONG 65W FOCUSING ITS
ENERGY OVER CENTRAL ARGENTINA. TO THE NORTHWEST...A LOW CENTERS
OVER THE EASTERN PACIFIC AT 25S 84W. A RIDGE TO THE EAST DOMINATES
MOST OF EASTERN AND SOUTHERN BRASIL INTO PARAGUAY CENTERING ON A
HIGH OVER SOUTHEASTERN PARAGUAY.

AT LOW LEVELS...THE SURFACE ANALYSIS SHOWS A 1002 HPA LOW AT 49S
70W EXTENDS A FRONT ALONG 42S 71W...43S 82W. RAINFALL WAS
OCCURRING IN COMODORO RIVADAVIA. A 996 HPA LOW AT 48S 49W EXTENDS
A FRONT ALONG 42S 55W...A 1002 HPA LOW AT 40S 65W. A 1014 HPA LOW
AT 37S 24W EXTENDS A FRONT ALONG 33S 34W...A 1014 HPA LOW AT 34S
42W...29S 49W...36S 58W. STRONG THUNDERSTORMS WERE OCCURRING
ACROSS CENTRAL ARGENTINA.


ARREAGA...INAMHI (ECUADOR)
DURAN...SENAMHI (PERU)
GALVEZ...WPC (USA)