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000
FXSA20 KWBC 241629
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1129 AM EST TUE JAN 24 2017

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

SYNOPSIS (VALID FROM JANUARY 24 AT 0000 UTC): AT 200 HPA...CELL OF
THE SUBTROPICAL RIDGE OVER THE PACIFIC BOUNDS BETWEEN 105W-80W AND
TO THE NORTH OF 50S...WHILE ANCHORING ON A CLOSED HIGH NEAR 23S
87W. THIS IS INDUCING THE NORTHWARD AMPLIFICATION OF A TROUGH FROM
THE BUENOS AIRES PROVINCE...ACROSS NORTHERN CHILE TO 20S 78W.
ANOTHER SHORT WAVE TROUGH TO THE EAST...MEANWHILE...EXTENDS FROM
30S 46W TO 13S 58W. THIS PATTERN FAVORS ORGANIZED DEEP CONVECTION
OVER BRASIL TO THE NORTH OF 10S AND EAST OF 60W...WHILE OTHER
CONVECTION CLUSTERED ACROSS CENTRAL BOLIVIA-SOUTHERN/CENTRAL PERU.

AT 500 HPA...BROAD CELL OF THE SUBTROPICAL RIDGE DOMINATES THE
FLOW OVER THE EASTERN PACIFIC TO THE NORTH OF 40S. THIS FAVORS A
TIGHT BELT OF MID LATITUDE WESTERLIES...WITH PROGRESSIVE
PERTURBATIONS EMBEDDING IN THIS FLOW AS THEY STREAM TOWARDS THE
SOUTHERN CONE OF SOUTH AMERICA. IN THIS FLOW...A SHORT WAVE TROUGH
CENTERS ON A CYCLONIC MAXIMA NEAR 47S 97W...WHILE A
STRONGER/HIGHER AMPLITUDE TROUGH EXTENDS FROM 60S 60W...ACROSS
PATAGONIA IN ARGENTINA...TO CONCEPCION IN CENTRAL CHILE.

AT LOW LEVELS...DEEP TROUGH ENTERED THE BELLINGSHAUSEN SEA...WHILE
ANCHORING ON AN OCCLUDED 974 HPA LOW AT 69S 96W. THIS EXTENDS A
FRONT ALONG A 982 HPA LOW AT 63S 81W...59S 83W...59S 93W...A 986
HPA LOW AT 60S 100W...55S 105W...49S 113W...AND 46S 120W. A FRONT
ON THE NORTHERN STREAM ORIGINATES ON AN OCCLUDED 982 HPA LOW AT
58S 54W...THEN ALONG A 982 HPA LOW AT 55S 51W...51S 52W...A 998
HPA LOW AT 49S 57W...46S 60W...CENTRAL PATAGONIA...A 1014 HPA LOW
AT 45S 74W...44S 74W...44S 82W...A 1010 HPA LOW AT 47S 91W...44S
87W...41S 93W...A 1006 HPA LOW AT 40S 104W...AND 36S 103W. AN
ELONGATED FRONT TO THE NORTH EXTENDS ALONG A 1018 HPA LOW AT 42S
18W...38S 25W...38S 40W...40S 55W...A 1002 HPA LOW AT 41S 63W...LA
PAMPA TO MENDOZA IN ARGENTINA. THIS SUSTAINS MODERATE CONVECTION
ACROSS CENTRAL PROVINCES IN ARGENTINA. ALSO ON THE NORTHERN
STREAM...A RIDGE OVER THE EASTERN PACIFIC ANCHORS ON A 1025 HPA
HIGH AT 30S 85W.

DURAN...SMN (ARGENTINA)
TEPES...DMC (CHILE)
DAVISON...WPC (USA)
$$





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