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
 
(Latest Discussion - Issued 1305Z Nov 25, 2014)
 
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
805 AM EST TUE NOV 25 2014

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

SYNOPSIS (VALID FROM NOVEMBER 25 AT 00UTC): THE 200 HPA ANALYSIS
SHOWS THE SUBTROPICAL RIDGE OVER THE CONTINENT...AS IT ENVELOPS
AREA TO THE NORTH OF 30S WHILE CENTERING ON A CLOSED HIGH OVER
BRASIL NEAR 13S 60W. THE RIDGE ALOFT IS VENTING ORGANIZED DEEP
CONVECTION THAT IS BUILDING ALONG A LINE FROM PERU/AMAZONAS IN
WESTERN BRASIL...RONDONIA/MATO GROSSO...TO SOUTHERN MINAS
GERAIS/SAO PAULO. A TUTT LOW TO THE EAST CENTERS NEAR 05S 31W.
THIS EXTENDS A TROUGH TO THE WEST/NORTHWEST ACROSS THE GUIANAS.
NORTHEAST BRASIL-AMAPA/NORTHERN PARA ARE ON THE
CONVERGENT/SUBSIDENT SIDE OF THE TROUGH/RIDGE PAIR.

THE 250 HPA JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH AXIS ALONG
56S 120W...57S 99W...51S 76W...EXITING AT 50S 55W. THE NORTHERN
POLAR HAS A FINGER BETWEEN 46S 72W AND 42S 59W. IT REFORMS AT 40S
55W...ALONG 42S 47W...A 149KT MAXIMUM AT 45S 37W...EXITING AT 43S
24W. THE SUBTROPICAL JET HAS ITS ENTRANCE AT 31S 66W...THEN ALONG
34S 58W...38S 46W...EXITING AT 38S 37W. IT HAS A BRANCH TO THE
NORTH WITH ENTRANCE AT 23S 66W...THEN ALONG 27S 58W...28S
46W...EXITING AT 23S 35W.

AT 500 HPA...IN A TIGHT BELT OF MID LATITUDE WESTERLIES...
PROGRESSIVE SHORT WAVE VORTICES ARE STREAMING BETWEEN 50S-60S
ACROSS THE SOUTH PACIFIC INTO TIERRA DEL FUEGO/SOUTHERN CONE.
SHORT WAVE TROUGHS POPULATE THE NORTHERN STREAM FLOW...WITH ONE
ALONG 110W WHILE ANOTHER STRETCHES ACROSS CENTRAL CHILE. FARTHER
EAST...AN ELONGATED TROUGH EXTENDS FROM 55S 47W...ALONG 47S
45W...45S 50W...TO THE BUENOS AIRES PROVINCE. THIS IS PROVIDING
DYNAMICAL SUPPORT TO AN AREA OF DEEP CONVECTION OVER NORTHERN
ARGENTINA-SOUTHERN BRASIL.

AT LOW LEVELS THE SURFACE ANALYSIS SHOWS A RIDGE ON THE NORTHERN
STREAM OVER THE FAR EASTERN PACIFIC THAT CENTERS ON A 1025 HPA
HIGH AT 38S 87W. SOUTH OF THIS RIDGE...IN A TIGHT BELT OF MID
LATITUDE WESTERLIES...A PROGRESSIVE FRONT IS STREAMING ACROSS THE
SOUTHERN CONE. IT ORIGINATES ON AN OCCLUDED 984 HPA LOW AT 58S
78W...ALONG A 980 HPA LOW AT 58S 73W...56S 69W...53S 71W...A 1004
HPA LOW AT 52S 76W...50S 77W...48S 85W...AND 48S 103W. THIS
SUSTAINS SCATTERED RAINS ACROSS SOUTHERN CHILE/TIERRA DEL FUEGO.
ANOTHER FRONT TO THE EAST EXTENDS FROM AN OCCLUDED 982 HPA LOW AT
53S 41W...THEN ALONG A 988 HPA LOW AT 54S 37W...52S 35W...49S
35W...A 990 HPA LOW AT 47S 37W...45S 35W...41S 39W...A 1002 HPA
LOW AT 42S 46W...38S 47W...33S 52W... NORTHERN URUGUAY TO
NORTHWEST ARGENTINA. THIS SUSTAINS ORGANIZED DEEP CONVECTION
ACROSS URUGUAY TO NORTHERN PROVINCES IN ARGENTINA. A RIDGE TO THE
SOUTH CENTERS ON A 1013 HPA HIGH AT 37S 61W. FARTHER EAST...AN
ELONGATED FRONT LIES ALONG A 1018 HPA LOW AT 33S 20W...30S
24W...28S 29W...27S 36W...24S 42W...TO SAO PAULO. THE FRONT SPLITS
A RIDGE IN TWO CELLS...WITH THE SOUTHERNMOST CENTERING ON A 1017
HPA HIGH AT 34S 35W...WHILE THE NORTHERNMOST CENTERS ON A 1025 HPA
HIGH AT 27S 15W.

CAROCA...DMC (CHILE)
DURAN...SENAMHI (PERU)
DAVISON...WPC (USA)
GALVEZ...WPC (USA)