THE WEATHER PREDICTION CENTER

COLLEGE PARK, MD


SOUTH AMERICAN SYNOPSIS




SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
944 AM EST FRI FEB 23 2018

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

SYNOPSIS (VALID FROM FEB 23 AT 0000 UTC): THE 200 HPA ANALYSIS
SHOWS CELL OF THE SUBEQUATORIAL RIDGE OVER NORTHERN SOUTH AMERICA
ENVELOPING CONTINENTAL AREA TO THE NORTH OF 25S WHILE ANCHORING ON
 A CLOSED HIGH OVER SANTA CRUZ BOLIVIA. THE RIDGE ALOFT IS VENTING
ORGANIZED DEEP CONVECTION ACROSS CENTRAL-NORTHERN BRASIL-NORTHERN
BOLIVIA AND CENTRAL PERU.

AT 250 HPA...THE JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH AXIS
ALONG 49S 120W...46S 111W...54S 94W...EXITING AT 59S 74W. IT
REFORMS AT 60S 63W...THEN ALONG 58S 40W...EXITING AT 61S 28W. THE
NORTHERN POLAR HAS ITS ENTRANCE AT 40S 113W...CROSSING A 148KT
MAXIMUM AT 43S 106W...48S 98W...A 121KT MAXIMUM AT 52S
90W...EXITING AT 51S 74W. THE JET REFORMS AT 45S 68W...CROSSING
45S 59W...41S 53W...EXITING AT 39S 47W. THE SUBTROPICAL JET HAS
ITS ENTRANCE AT 35S 117W...THEN ALONG 41S 103W...EXITING AT 45S
87W. IT REFORMS AT 42S 68W...THEN ALONG 41S 58W...EXITING AT 37S
50W. ANOTHER BRANCH OF THE SUBTROPICAL HAS ITS ENTRANCE AT 24S
54W...THEN ALONG 27S 44W...37S 38W...EXITING AT 44S 26W. AT 150
HPA...THE SUBEQUATORIAL JET HAS ITS ENTRANCE AT 05S 49W...CROSSING
00N 56W...AND EXITING AT 03S 59W. ANOTHER FINGER TO THE EAST
EXTENDS BETWEEN 01S 48W AND EASTERN FRENCH GUIANA.

AT 500 HPA...A LONG WAVE TROUGH OVER THE SOUTH PACIFIC EXTENDS
NORTH BETWEEN 130W-90W TO 30S. EAST OF THIS AXIS...SHORT WAVE
PERTURBATIONS POPULATE THE SOUTHERN AND NORTHERN STREAM FLOW. ON
THE SOUTHERN STREAM ONE IS STREAMING TOWARDS THE BELLINGSHAUSEN
SEA-TIERRA DEL FUEGO AS ANOTHER MEANDERS BETWEEN THE WEDDEL
SEA/SOUTH GEORGIA ISLANDS. ON THE NORTHERN STREAM...A SHORT WAVE
TROUGH LIES OFF THE CENTRAL COAST OF CHILE...WHILE OVER THE
WESTERN ATLANTIC THREE SHORT WAVE PERTURBATIONS COMBINE IN SUPPORT
OF A TROUGH OFF THE COAST OF BRASIL.

AT LOW LEVELS...AN ELONGATED FRONT STRETCHES FROM A 990 HPA LOW AT
60S 51W...ALONG 57S 50W...56S 59W...56S 71W...A 986HPA LOW AT 59S
78W...55S 79W...53S 86W...A 982 HPA LOW AT 52S 95W...45S 98W...TO
39S 105W. ANOTHER FRONT TO THE NORTH EXTENDS ALONG A 986 HPA LOW
AT 62S 37W...59S 33W...54S 39W...A 1014 HPA LOW AT 54S 45W...51S
46W...50S 51W...A 1014 HPA LOW AT 45S 54W...40S 52W...36S
59W...38S 66W...A 1012 HPA LOW AT 37S 73W...34S 74W...34S 76W...A
1018 HPA LOW AT 34S 80W...30S 82W...30S 85W...TO A 1018 HPA LOW AT
31S 88W. SCATTERED CONVECTION WAS CLUSTERING ALONG THE LEE OF THE
ANDES BETWEEN CUYO IN ARGENTINA TO SOUTHERN BOLIVIA. ON THE
NORTHERN STREAM...AN OCCLUDED 990 HPA LOW AT 45S 30W EXTENDS A
FRONT ALONG 998 HPA LOW AT 45S 26W...42S 25W...40S 28W...A 1006
HPA LOW AT 38S 31W...36S 32W...34S 34W...A 1006 HPA LOW AT 36S
37W...31S 37W...27S 37W... NORTHERN SAO PAULO-MATO GROSSO TO
NORTHERN BOLIVIA. ORGANIZED DEEP CONVECTION CLUSTERED ALONG AND
NORTH OF THIS BOUNDARY. A RIDGE TO THE SOUTH CENTERS ON A 1017 HPA
HIGH AT 34S 56W.

POMIER...SENAMHI (BOLIVIA)
BALBINO...INMET (BRASIL)
DAVISON/GALVEZ...WPC (USA)




Last Updated: 944 AM EST FRI FEB 23 2018