Rarity: Potential Cyclone in Southern Hemisphere

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Invest Off the Coast of Brazil


SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
847 AM EST WED MAR 10 2010

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

SYNOPSIS (VALID FROM 00Z MAR 10). THE UPPER LEVEL ANALYSIS SHOWS
A CLOSED LOW NEAR 33S 45W EXTENDING A SHORT WAVE TROUGH TO THE
NORTHWEST INTO BRASIL ALONG 20S 50W. THIS FEATURE IS DECOUPLING
FROM A WARM CORE SURFACE LOW OFF THE COAST OF BRASIL...WITH
CLOSED CIRCULATION ESTIMATED NEAR 29.6S 48.2W. ALTHOUGH A
TIGHT/COMPACT STORM...IT IS NOW CLASSIFIED AS A TROPICAL CYCLONE
RATHER THAN SUBTROPICAL. FARTHER NORTH...A NARROW RIDGE STRETCHES
ACROSS NORTHERN BRASIL WHILE STRUNG ALONG CLOSED HIGHS AT 07S 65W
AND 19S 35W. THE RIDGE ALOFT IS VENTING SCATTERED DEEP CONVECTION
FROM CENTRAL/NORTHERN PERU...ACROSS AMAZONAS/PARA IN WESTERN
BRASIL TO BAHIA/ESPIRITO SANTO IN EASTERN BRASIL.

THE 250 HPA JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH AXIS ALONG
56S 120W...55S 106W...EXITING AT 59S 94W. IT HAS A FINGER BETWEEN
62S 63W AND 60S 41W. THE NORTHERN POLAR LIES ALONG A 172KT
MAXIMUM AT 54S 121W...51S 106W...EXITING AT 53S 90W. IT REFORMS
AT 51S 80W...ACROSS TIERRA DEL FUEGO...A 158KT MAXIMUM AT 58S
45W...48S 31W...EXITING AT 40S 15W. THE SUBTROPICAL JET LIES
ALONG 38S 120W...EXITIGN AT 32S 105W. IT REFORMS AT 43S
91W...ALONG 48S 75W...LAS MALVINAS...53S 55W...48S 38W...EXITING
AT 41S 27W. IT HAS A FINGER FARTHER TO THE NORTH WITH ENTRANCE AT
21S 45W...ALONG 25S 40W...EXITING AT 30S 37W.

THE 500 HPA ANALYSIS SHOWS A TIGHT BELT OF MID/UPPER LATITUDE
WESTERLIES ACROSS THE SOUTH PACIFIC...WITH PROGRESSIVE SHORT WAVE
PERTURBATIONS STREAMING TOWARDS THE SOUTHERN CONE. IN THIS
PATTERN A SHORT WAVE TROUGH IS INITIALIZED ALONG 107W AND SOUTH
OF 48S...WHILE ANOTHER ENTERED SOUTHERN CHILE/TIERRA DEL FUEGO. A
LOW AMPLITUDE TROUGH MEANDERS ACROSS THE ANTARCTIC PENINSULA/
WEDDELL SEA...WHILE A SHORT WAVE TROUGH LIES JUST EAST OF THE
SOUTH GEORGIA ISLANDS. ON THE NORTHERN STREAM...MEANWHILE...A LOW
AT 41S 64W ANCHORS A SHORT WAVE TROUGH OVER NORTHERN PATAGONIA/LA
PAMPA IN ARGENTINA. A MID LEVEL CYCLONE TO THE NORTH CENTERS NEAR
31S 48W...AND IT IS A REFLECTION OF THE AFOREMENTIONED UPPER
LOW/TROUGH ACROSS SOUTHERN/SOUTHEAST BRASIL.

THE SURFACE ANALYSIS SHOWS A RIDGE ON THE NORTHERN STREAM FLOW
OVER THE FAR EASTERN PACIFIC...CENTERING ON THREE HIGHS...A 1027
HPA AT 35S 92W...A 1025 HPA AT 44S 87W...AND ANOTHER 1025 HPA AT
41S 106W. A PROGRESSIVE POLAR FRONT TO THE SOUTH LIES ALONG A 966
HPA LOW AT 69S 101W...A 978 HPA LOW AT 64S 87W...60S 84W...56S
86W...54S 94W...56S 96W...A 970 HPA TRIPLE POINT LOW AT 58S
101W...52S 102W...AND 46S 110W. AN ELONGATED FRONT LIES TO THE
EAST AND NORTH AS IT ORIGINATES ON A 990 HPA LOW AT 56S
71W...ALONG 994 HPA LOW AT 56S 66W...50S 65W...46S 69W...44S
75W...42S 81W...41S 87W...TO A 1022 HPA LOW AT 40S 94W. A THIRD
BOUNDARY IS INITIALIZED OVER THE WESTERN ATLANTIC...WITH AXIS
ALONG A 1010 HPA LOW AT 50S 57W...48S 58W...46S 60W...A 1012 HPA
LOW AT 41S 63W...38S 61W...33S 64W...TO MENDOZA IN ARGENTINA.
SCATTERED CONVECTION WAS BUILDING ACROSS THE BUENOS AIRES
PROVINCE. A RIDGE TO THE EAST CENTERS ON TWO 1021 HPA
HIGHS...WITH ONE AT 38S 49W AND THE OTHER AT 46S 44W. A TROPICAL
DEPRESSION OFF THE SOUTHERN COAST OF BRASIL CENTERS ON AN
ESTIMATED 1006 HPA LOW NEAR 29.6S 48.2W.

FLORES...SENAMHI (PERU)
LLANQUE...SENAMHI (BOLIVIA)
DAVISON...HPC (USA)

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