Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2
000
FXSA20 KWBC 061348
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
948 AM EDT FRI MAY 06 2016

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

SYNOPSIS (VALID FROM MAY 06 AT 0000 UTC): AT 200 HPA...A WELL
DEFINED TROUGH EXTENDS ITS AXIS ACROSS NORTHERN
BOLIVIA-ACRE-NORTHERN PERU. THIS TROUGH HAS LIMITED EFFECTS ON
CONVECTION DUE TO THE PRESENCE OF A STABLE AIR MASS AT LOW-LEVELS.
THE ONLY REGIONS WITH PULSING DIURNAL CONVECTION ARE PARA/MATO
GROSSO...WHERE VENTILATION IN THE SOUTHERN PERIPHERY OF THE
SUBEQUATORIAL RIDGE IS OCCURRING.

THE UPPER JET ANALYSIS SHOWS THE SOUTHERN POLAR JET ALONG A 130KT
MAXIMA AT 62S 15W...47S 51W...42S 29W. THE NORTHERN POLAR JET
EXTENDS ALONG 36S 120W...38S 109W...EXITING AT 33S 93W. A FINGER
FORMS AT 33S 75W AND EXITS AT 30S 64W. IT REFORMS AT 31S 60W ALONG
A 142KT MAXIMA AT 36S 42W...EXITING AT 33S 25W. THE SUBTROPICAL
EXTENDS ALONG A 129KT MAXIMA AT 30S 113W...25S 94W...EXITING AT
23S 68W. IT REFORMS AT 31S 46W EXITING AT 28S 28W.

AT 500 HPA...A STRONG AND WELL DEFINED RIDGE CONTINUES EXTENDING
FROM CENTRAL ARGENTINA INTO THE DRAKE PASSAGE AND THE
BELLINGSHAUSEN SEA. THIS RIDGE IS BLOCKING THE ENTRANCE OF
PERTURBATIONS ACROSS THE SOUTHERN CONE. TO THE NORTH OF THIS
RIDGE...A SHORT WAVE TROUGH EXTENDS FROM 48 80 ACROSS BIO
BIO/MAULE IN CHILE INTO MENDOZA IN ARGENTINA. THIS TROUGH IS
FOCUSING CYCLONIC VORTICITY ADVECTION INTO CENTRAL PORTIONS OR
ARGENTINA/NORTHERN PATAGONIA WHERE RAINFALL WAS OCCURRING. A BROAD
NORTHERN STREAM EXTENDS ALONG 80W-60W AND NORTH INTO SOUTHERN
PERU/NORTHERN BOLIVIA. THIS TROUGH IS AIDING WITH CONVECTIVE
DEVELOPMENT IN PARAGUAY/SE BOLIVIA.

AT LOW LEVELS...A 998 HPA LOW AT 50S 46W EXTENDS A FRONT ALONG 47S
55W...50S 61W...61S 68W...69S 77W. AN ELONGATED RIDGE EXTENDS FROM
THE DRAKE PASSAGE INTO THE RIO DE LA PLATA. THIS RIDGE IS ANCHORED
ON THREE 1025HPA HIGHS. ONE CENTERS AT 43S 62W...ANOTHER AT 52S
68W...AND 58S 72W. A WEAKENING FRONT EXTENDS OFF THE COAST OF
CHILE ALONG A 1014 HPA LOW AT 51S 82W...45S 79W...A 1014 HPA LOW
AT 38S 79W...INTO A 1014 HPA OCCLUDED LOW AT 36S 75W. A COLD FRONT
EXTENDS FROM THE 1014 HPA LOW AT 38S 78W ALONG CONCEPCION...35S
72W...30S 75W. SCATTERED RAINFALL WAS OCCURRING IN PARTS OF CHILE
AND THE INTERIOR OF PATAGONIA. A 1018 HPA LOW AT 36S 48W EXTENDS A
FRONT ALONG 34S 55W...36S 66W. SCATTERED RAINFALL WAS OCCURRING IN
CENTRAL ARGENTINA.  ANOTHER FRONT EXTENDS ALONG 27S 33W...A 1018
HPA LOW AT 22S 40W...22S 47W...A 1018 HPA LOW AT 26S 57W...AND A
FORMING COLD FRONT INTO 18S 64W. SCATTERED STRONG CONVECTION WAS
OCCURRING IN CENTRAL AND NORTHERN PARAGUAY.

AYALA...DINAC (PARAGUAY)
ENRIQUEZ...DGAC (ECUADOR)
GALVEZ...WPC (USA)
$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.