SOUTH AMERICA FORECAST DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
132 PM EDT WED JUL 17 2024

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

SOUTH AMERICAN FORECAST BULLETIN FOR 17 JUL 2024 AT 1730 UTC:
ON WEDNESDAY...DRY CONDITIONS ARE EXPECTED OVER MUCH OF NORTHERN
BRASIL WITH A UPPER LEVEL HIGH PRESSURE SYSTEM EXTENDING INTO THE
REGION...AS WELL AS INTO BOLIVIA AND PARAGUAY. THIS HIGH PRESSURE
SYSTEM IS EXPECTED TO MAINTAIN MUCH OF THE PASSING TROUGHS AND
TROPICAL WAVES ALONG THE ITCZ/NET OVER THE NORTHERN MOST PORTION
OF THE CONTINENT. SIGNIFICANT RAINFALL IS NOT EXPECTED OVER THE
NEXT SEVERAL DAYS. ON WEDNESDAY AND THURSDAY...MAXIMA OF 15-25MM
ARE EXPECTED OVER FROM THE GUIANAS...TO SOUTHERN VENEZUELA...AND
INTO RORAIMA AND NORTHERN AMAZONAS-BRASIL. ON FRIDAY...AN INCREASE
IN AMOUNT OF AVAILABLE MOISTURE IS EXPECTED AND COULD REACH GUYANA
AND VENEZUELA...WITH THE PASSING OF A TROUGH...WHERE IT WILL FAVOR
MAXIMA OF 20-35MM.

IN THE SOUTHERN PORTION OF THE CONTINENT...AN APPROACHING UPPER
LEVEL TROUGH IS LOCATED JUST WEST OF CHILE...WHILE ANOTHER WEAK
UPPER LEVEL TROUGH IS MOVING AWAY FROM THE CONTINENT OVER URUGUAY
AND SOUTHERN BRASIL. IN THE LOWER LEVELS...POTENT HIGH PRESSURE
SYSTEMS ARE LOCATED OVER BOTH THE ATLANTIC AND PACIFIC OCEANS NEAR
THE CONTINENT. THE LOWER LEVEL CONDITIONS ARE EXPECTED TO DOMINATE
AND ENHANCE OVER THE NEXT SEVERAL DAYS. A FRONTAL SYSTEM IS
PASSING OVER THE CENTRAL PORTION OF CHILE INTO SOUTHERN ARGENTINA
ON WEDNESDAY. AN ATMOSPHERIC RIVER ASSOCIATED WITH THIS SYSTEM IS
BRINGING PRECIPITABLE WATER AMOUNTS BETWEEN 20-30MM...SUPPORTING
PRECIPITATIONS TOTALS OF 25-50MM FROM ARAUCANIA TO LOST LAGOS IN
CHILE. HIGHER ELEVATIONS CAN EXPECT SNOW.  AYSEN-CHILE CAN EXPECT
LOWER AMOUNTS OF 15-20MM. WESTERN SANTA CRUZ CAN EXPECT SNOW
ACCUMULATIONS OF 01-05CM. ON THURSDAY...AS THE COLD FRONT
CONTINUES PUSHING NORTHWARD FROM VALPARAISO-CHILE...INTO CENTRAL
ARGENTINA...THE PRESSURE GRADIENT INCREASES IN THE LOWER LEVELS
AND THE SALLJ IS EXPECTED FROM CENTRAL BOLIVIA INTO NORTHERN
ARGENTINA...INCREASING MOISTURE TRANSPORT INTO THE REGION.
NORTHEAST ARGENTINA CAN EXPECT MAXIMA OF 15-20MM. THE PASSING OF
THE COLD FRONT...EXPECT SNOW ACCUMULATIONS OF 15-30CM IN THE
HIGHER ELEVATIONS FROM MAULE TO SANTIAGO METROPOLITAN REGION. IN
MAGALLANES-CHILE...A FRONTAL SYSTEM ENTERS THE REGION AND FAVORS
MAXIMA OF 15MM. ON FRIDAY...AN UPPER LEVEL TROUGH IS DEVELOPING
INTO A CUTOFF LOW TO THE WEST OF NORTHERN CHILE...WHILE THE
SUBTROPICAL JET IS POSITIONED OVER CENTRAL ARGENTINA ...FAVORING
THE DIVERGENT SIDE OF THE JET OVER NORTHERN ARGENTINA INTO
URUGUAY. IN THE LOWER LEVELS...THE SALLJ CONTINUES TO TRANSPORT
MOISTURE INTO NORTHERN ARGENTINA AND URUGUAY...FAVORING
PRECIPITATION. NORTHERN ARGENTINA CAN EXPECT MAXIMA OF
15MM...WHILE URUGUAY CAN EXPECT MAXIMA OF 15-25MM. TO THE SOUTH IN
CHILE...AS THE WARM FRONT HAS PASSED...EXPECT MAXIMA OF 20-35MM
WITH A CHANCE OF RAIN/SNOW.

ACOSTA...(WPC)