SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
830 AM EST FRI NOV 06 2009
 
GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/
 
SYNOPSIS (VALID FROM 00Z NOV 06). SATELLITE IR IMAGERY SHOWS
ORGANIZED DEEP CONVECTION BUILDING ACROSS THE CONTINENT TO THE
NORTH OF 25S. THE ACTIVITY SPLITS IN TWO SECTORS...WITH ONE
ACROSS SOUTHERN BRASIL-PARAGUAY/MATO GROSSO DO SUL ASSOCIATING
WITH A FRONT. THE OTHER TO THE NORTH IS DEVELOPING ALONG A BELT
BOUND BETWEEN 20S-08S...WITH MOST INTENSE ACROSS THE PERUVIAN
JUNGLE-RONDONIA/NORTHERN BOLIVIA TO MATO GROSSO IN BRASIL.
ALOFT...THE 200 HPA ANALYSIS SHOWS A RIDGE EXTENDING FROM THE
GALAPAGOS ISLANDS...TO THE SOUTHEAST ACROSS BOLIVIA-SOUTHEAST
BRASIL TO THE WESTERN ATLANTIC. TWO CLOSED HIGHS ANCHOR THIS
RIDGE...ONE OVER BOLIVIA NEAR 13S 67W AND THE OTHER OVER THE
ATLANTIC NEAR 27S 45W. A CLOSED LOW FORMED NEAR 10S
37W...EXTENDING A TROUGH TO NORTHEAST BRASIL/THE GUIANAS. THIS
FAVORS A CONVERGENT PATTERN ALOFT TO THE EAST OF 45W...WHERE IT
IS INHIBITING DEEP CONVECTION.

THE JET ANALYSIS AT 250 HPA SHOWS THE SOUTHERN POLAR WITH AXIS
ALONG 71S 100W...EXITING AT 59S 84W. IT HAS A FINGER BETWEEN 54S
78W AND 44S 80W. THE SOUTHERN POLAR REFORMS AT 41S 75W...ALONG
45S 61W...50S 49W...EXITING OVER THE SOUTH GEORGIA ISLANDS. THE
NORTHERN POLAR HAS ITS ENTRANCE AT 50S 105W...CROSSING 42S 94W...
38S 90W..EXITING AT 34S 85W. THE JET REFORMS AT 33S 76W...ALONG A
166KT MAXIMUM AT 38S 60W...A 185KT MAXIMUM AT 43S 42W...44S
29W...AND A 180KT MAXIMUM AT 36S 08W. THE SUBTROPICAL JET HAS A
FINGER BETWEEN 34S 95W AND 26S 87W. IT REFORMS FARTHER TO THE
NORTH NEAR 18S 83W...ALONG 28S 68W...SOUTHERN URUGUAY...39S
29W...EXITING AT 26S 07W.

THE 500 HPA ANALYSIS SHOWS A RIDGE OVER THE PACIFIC WITH AXIS
SOUTH BETWEEN 115W-90W. A SOUTHERN STREAM SHORT WAVE TROUGH IS
MOVING UNDER THIS RIDGE...WITH TROUGH ACROSS THE BELLINGSHAUSEN
SEA...60S 85W...TO 57S 100W. AN INDUCED/SHORT WAVE RIDGE ACROSS
THE DRAKE PASSAGE/NORTHERN TIP OF THE ANTARCTIC PENINSULA
SEPARATES THIS TROUGH FROM A HIGHER AMPLITUDE TROUGH THAT EXTENDS
TO THE NORTHWEST ALONG A CLOSED LOW AT 57S 50W...LAS MALVINAS/
FALKLAND ISLANDS...PATAGONIA...40S 80W...TO 35S 90W. THE TROUGH
IS FOCUSING ITS SHORT WAVE ENERGY ACROSS SOUTHERN CHILE/
PATAGONIA...AND IT ALSO FAVORS LEE SIDE PERTURBATIONS ACROSS
CENTRAL CHILE TO CENTRAL ARGENTINA.

AT LOW LEVELS...A SURFACE RIDGE OVER THE EASTERN PACIFIC CENTERS
ON A 1037 HPA HIGH AT 52S 106W. TO THE SOUTH AND EAST OF THIS
RIDGE...A PROGRESSIVE FRONT LIES ALONG A 986 HPA LOW AT 65S
72W...A 1004 HPA LOW AT 58S 80W...55S 88W...AND 55S 98W. EAST OF
THIS SYSTEM..A BROAD TROUGH LIES OVER THE WESTERN ATLANTIC AND
THE SOUTHERN CONE...WITH AN OCCLUDED 974 HPA LOW AT 58S 51W. A
POLAR FRONT TO THE NORTH LIES ALONG A 982 HPA LOW AT 53S
48W...48S 46W...A 998 HPA LOW AT 48S 49W...44S 51W...42S 56W...A
1006 HPA LOW AT 41S 60W...LA PAMPA-A 1012 HPA LOW AT 41S
70W...CONCEPCION CHILE...TO A 1024 HPA LOW AT 37S 81W. SNOW
SHOWERS WERE REPORTED OVER TIERRA DEL FUEGO...WHILE SCATTERED
RAINFALL AFFECTED COASTAL STATIONS IN SOUTHERN CHILE. FARTHER TO
THE NORTH...AN OLD FRONT LIES ALONG A 1014 HPA LOW AT 37S
35W...35S 39W...35S 45W...RIO GRANDE DO SUL...CENTRAL MESOPOTAMIA
TO JUJUY/SALTA IN NORTHWEST ARGENTINA. SCATTERED COVNECTION WAS
NOTED ALONG THIS BOUNDARY. 

FERNANDES...CHM (BRASIL)
GARCIA...SENAMHI (PERU)
DAVISON...HPC (USA)