TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
253 PM EDT THU MAY 16 2024

FORECAST BULLETIN 16 MAY 2024 AT 1900 UTC:
NOTE: THE NATIONAL HURRICANE CENTER IS MONITORING A REGION FOR
POSSIBLE TROPICAL CYCLONE DEVELOPMENT OVER THE NEXT SEVERAL DAYS
IN THE EASTERN PACIFIC...JUST SOUTH OF MEXICO AND GUATEMALA.
PLEASE CHECK THE NHC WEBSITE FOR UPDATES ON THE DEVELOPMENT.

A POTENT UPPER LEVEL RIDGE IS LOCATED OVER CENTRAL AMERICA AND
EXTENDS INTO THE WESTERN CARIBBEAN ON THURSDAY. IN ADDITION...A
MID LEVEL RIDGE CONTINUES TO DOMINATE MOST OF THE WESTERN
CARIBBEAN AND INTO THE EASTERN MEXICO AND CENTRAL AMERICA. THESE
CONDITIONS ARE FAVORING A TRADE WIND INVERSION CAP AT AROUND THE
900 TO 850HPA LEVELS IN MOST OF THE WESTERN CARIBBEAN
BASIN...LIMITING DEEP CONVECTION OVER THE REGION. GENERALLY DRY
CONDITIONS ARE EXPECTED OVER THE GREATER ANTILLES ON THURSDAY AND
ARE EXPECTED TO CONTINUE OVER THE NEXT THREE DAYS. MOST OF THE
COUNTRY OF MEXICO IS EXPERIENCING DRIER CONDITIONS AS PRECIPITABLE
WATER LEVELS ARE EXPECTED TO REMAIN LOW OVER THE WESTERN AND
CENTRAL PORTIONS OF THE COUNTRY. A MOSTLY ZONAL FLOW IS EXPECTED
ON THURSDAY...FAVORING THESE CONDITIONS.

IN CENTRAL AMERICA...THE PASSING OF TROUGHS OVER THE REGION WITH
HIGH AMOUNTS OF PRECIPITABLE WATER IS EXPECTED TO BRING HEAVY
PRECIPITATION OVER THE NEXT SEVERAL DAYS. ALTHOUGH A GENERAL RIDGE
SET UP IS EXPECTED OVER THE EASTERN PACIFIC IN THE UPPER
LEVELS...THE PACIFIC REGION WEST AND SOUTH OF GUATEMALA...EL
SALVADOR...NICARAGUA...AND COSTA RICA IS EXPERIENCING ABOVE NORMAL
SST VALUES...FROM 1 TO 3 DEGREES ABOVE NORMAL. THE SST POSITIVE
ANOMALIES WILL FAVOR THE ENHANCEMENT OF A TROUGH OFFSHORE CENTRAL
AMERICA AND INCREASE ONSHORE FLOW INTO THE CONTINENTAL DIVIDE.
WITH THE HIGH AMOUNTS OF PRECIPITABLE WATER AND INCREASE IN THE
FLOW FROM THE SOUTH AND SOUTHEAST...MOISTURE CONVERGENCE IS
EXPECTED TO PLAY AN IMPORTANT ROLE IN THE HEAVY PRECIPITATION. ON
THURSDAY...WESTERN COSTA RICA CAN EXPECT MAXIMA OF 50-100MM.
MOISTURE CONVERGENCE IS EXPECTED INTO EASTERN NICARAGUA WITH THE
EASTERLY TRADE WINDS ADVECTING MOISTURE...AND FROM EASTERN
NICARAGUA INTO EASTERN COSTA RICA...AND NORTHWEST PANAMA...CAN
EXPECT MAXIMA OF 35-70MM. THE PACIFIC COASTAL REGIONS FROM EXTREME
SOUTHERN CHIAPAS...TO THE GOLFO DE FONSECA REGION CAN EXPECT
MAXIMA OF 20-45MM. ON FRIDAY...THE TROUGH IS EXPECTED TO CONTINUE
MOVING NORTH AND WEST...WHERE FROM THE GOLFO DE FONSECA REGION TO
GUANACASTE IN COSTA RICA CAN EXPECT MAXIMA OF 40-80MM. SOUTHERN
CHIAPAS INTO SOUTHERN GUATEMALA CAN EXPECT MAXIMA OF 20-45MM WITH
THE CONTINUED SOUTHERLY ONSHORE FLOW. ON SATURDAY...THE TROUGH IS
EXPECTED TO CONTINUE MOVING ALONG THE COASTAL REGIONS OF GUATEMALA
AND CHIAPAS/OAXACA. VERACRUZ...CHIAPAS...TABASCO...AND EASTERN
OAXACA ARE EXPECTED TO SEE MAXIMA OF 40-80MM. WESTERN REGIONS OF
OAXACA AND SOUTH-CENTRAL GUATEMALA CAN EXPECT MAXIMA OF 20-35MM.

IN NORTHERN SOUTH AMERICA...THE AFOREMENTIONED UPPER LEVEL RIDGE
OVER THE EASTERN PACIFIC OCEAN EXTENDS INTO COLOMBIA AND WESTERN
VENEZUELA....WHILE THE BASE OF AN UPPER LEVEL TROUGH IS EXPECTED
OVER CENTRAL VENEZUELA. INTERACTIONS WITH AN UPPER LEVEL RIDGE IN
CENTRAL BRASIL IS EXPECTED TO ENHANCE DIVERGENCE ALONG NORTHERN
BRASIL...INTO SOUTHERN VENEZUELA...AND THE GUIANAS OVER THE
FORECAST PERIOD. IN ADDITION...EASTERLY WAVES ARE EXPECTED TO
PROPAGATE OVER THE REGION AND FAVOR HIGHER AMOUNTS OF PRECIPITABLE
WATER AND DEEP CONVECTION AS THEY ENCOUNTER UPPER DIVERGENCE FROM
THE UPPER LEVEL. ON THURSDAY...AN EASTERLY WAVE WILL FAVOR MAXIMA
OF 30-60MM IN NORTH CENTRAL COLOMBIA...INTO WESTERN VENEZUELA.
WHILE INTERACTIONS WITH THE ITCZ AND TROUGHS/EASTERLY WAVES...WILL
FAVOR MAXIMA OF 20-45MM IN SOUTHERN VENEZUELA...INTO RORAIMA.
SIMILAR AMOUNTS ARE EXPECTED ALONG THE ATLANTIC COASTAL REGIONS
FROM GUYANA...TO AMAPA...WITH THE ADVECTION OF MOISTURE INTO THE
REGION THROUGH THE EASTERLY TRADE WINDS. ON FRIDAY...A MAXIMA OF
40-80MM IS EXPECTED FROM RORAIMA TO SOUTH GUYANA...AND INTO
WESTERN FRENCH GUIANA AS A TROUGH INTERACTS WITH THE ITCZ. AN
EASTERLY WAVE OVER CENTRAL VENEZUELA WILL FAVOR GENERALIZED MAXIMA
OF 20-45MM FROM CENTRAL VENEZUELA INTO SOUTHERN COLOMBIA/NORTHERN
AMAZONAS-BRASIL. AN EASTERLY WAVE OVER COLOMBIA WILL FAVOR
GENERALIZED MAXIMA OF 20-35MM IN THE REGION. ON SATURDAY...THE AN
EASTERLY WAVE PROPAGATES INTO EASTERN COLOMBIA...WHILE THE UPPER
LEVEL TROUGH RETROGRADES INTO THE REGION. THIS WILL FAVOR UPPER
DIVERGENCE ALONG THE EASTERLY WAVE...AND MAXIMA OF 35-70MM.
SIMILAR AMOUNTS ARE EXPECTED ALONG THE ITCZ IN CENTRAL VENEZUELA.
AS MORE MOISTURE IS EXPECTED TO PROPAGATE INTO THE GUIANAS ALONG
THE ITCZ...MORE CONVERGENCE IS EXPECTED TO ENHANCE HEAVY
PRECIPITATION IN THE REGION. WITH THE INTERACTIONS OF AN EASTERLY
WAVE OVER FRENCH GUIANA...EXPECT MAXIMA OF 30-60MM.

ACOSTA...WPC (USA)