618
FXCA20 KWBC 291830
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
230 PM EDT WED MAY 29 2024

FORECAST BULLETIN 29 MAY 2024 AT 1830 UTC:

FOR THE LATTER PART OF THE WORKWEEK...THE A FEW TROPICAL WAVES
WILL BE PASSING THROUGH THE CARIBBEAN AND NORTHERN SOUTH AMERICA.
THE COMBINATION OF THE INCREASE IN MOISTURE WITH DIURNAL HEATING
WILL CAUSE SOME AREAS OF NORTHERN SOUTH AMERICA TO HAVE ENHANCED
CHANCE OF SHOWERS AND THUNDERSTORMS OVER THE AREA. IN ADDITION...A
COUPLE OF TROPICAL WAVES WILL MOVE INTO THE CARIBBEAN AND CENTRAL
AMERICA TODAY AND LATE FRIDAY. AS THE TROPICAL WAVE EXPECTED TODAY
INTO THURSDAY APPROACHES CENTRAL AMERICA...IT WILL INTERACT WITH A
MID LEVEL TROUGH...CAUSING A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS OVER EASTERN NICARAGUA. IN FACT...EACH DAY FOR THE
REST OF THE WORKWEEK...RAINFALL MAXIMA OVER EASTERN NICARAGUA IS
FORECAST TO BE UP TO 125 MM TODAY...100 MM ON THURSDAY INTO EARLY
FRIDAY...AND 50 MM FROM FRIDAY INTO EARLY SATURDAY. THAT BEING
SAID...THERE IS SOME UNCERTAINTY ON THE POTENTIAL DEVELOPMENT OF A
SURFACE LOW OVER THE WESTERN CARIBBEAN...AS THE GFS MODEL SUGGESTS
A LOW PRESSURE FORMING BY FRIDAY TO THE EAST OF NICARAGUA AND
COSTA RICA...BUT THE OTHER GLOBAL MODELS ARE NOT AS BULLISH WITH
THE DEVELOPMENT OF THE LOW. REGARDLESS OF THE DEVELOPMENT OF THIS
SFC LOW...SIGNIFICANT AMOUNTS OF RAIN COULD AFFECT PORTIONS OF
CENTRAL AMERICA...ESPECIALLY EASTERN NICARAGUA. THE GFS MODEL IS
SUGGESTING A TOTAL RAINFALL ACCUMULATION...FROM TODAY THROUGH
EARLY SATURDAY...OF AROUND 200 MM ACROSS ISOLATED AREAS OF
SOUTHEASTERN NICARAGUA.

IT IS ALSO WORTH MENTIONING THAT DEEP MOISTURE FROM ANOTHER
TROPICAL WAVE MOVING INTO THE CARIBBEAN ON FRIDAY INTO SATURDAY
WILL POOL OVER THE CENTRAL TO WESTERN CARIBBEAN THIS WEEKEND. A
COLD FRONT OVER THE WESTERN ATLANTIC WILL MOVE EAST...BUT A
STATIONARY FRONT WILL PERSIST OVER THE NORTHERN CARIBBEAN ISLANDS
INTO AND THE BAHAMAS. THE COMBINATION OF THE DEEP
MOISTURE...STATIONARY FRONT KEEPING THE MOISTURE OVER THE
CARIBBEAN...AND A MID TO UPPER LEVEL TROUGH...WILL GRADUALLY CAUSE
DEEP MOISTURE TO ELONGATE AND MOVE OVER THE NORTH CENTRAL
CARIBBEAN ISLANDS...INCLUDING JAMAICA AND HISPANIOLA THIS
WEEKEND...POSSIBLY CAUSING A MORE GENERALIZED RAINFALL PATTERN
OVER THE ISLANDS. CONFIDENCE IS LOW ON THIS SETUP THOUGH...AS THE
MODEL GUIDANCE IS NOT IN GREAT AGREEMENT. THAT BEING SAID...SOME
RAIN IS EXPECTED ON THE LATTER PART OF THE WORKWEEK...WITH
ISOLATED DAILY MAX RAINFALL OF AROUND 25-40 MM OVER THE NORTHERN
CARIBBEAN ISLANDS FROM TODAY UNTIL SATURDAY MORNING...THOUGH
ISOLATED HIGHER AMOUNTS ARE POSSIBLE.

ACROSS NORTHERN SOUTH AMERICA...MANY SECTIONS WILL OBSERVE
SIGNIFICANT RAINFALL...WITH DAILY MAX TOTALS GENERALLY BETWEEN 25
AND 60MM DEPENDING ON THE AREA. THIS IS DUE TO THE COMBINATION OF
THE DIFFLUENCE ALOFT WITH THE PASSING TROPICAL WAVES AND DIURNAL
HEATING. THE GFS MODEL RAINFALL SOLUTION SEEMS MORE ADEQUATE THAN
THEN ECMWF FOR THAT REGION...CONSIDERING THE NATURE OF THE
EXPECTED WEATHER...WHICH IS THAT OF PULSE THUNDERSTORMS. THE 3-DAY
RAINFALL ACCUMULATION ACROSS VENEZUELA COULD BE AS MUCH AS 200 MM
OVER ISOLATED AREAS...WITH THE MAJORITY OF OTHER AREAS...INCLUDING
NORTHERN BRAZIL...THE GUIANAS...AND COLOMBIA...HAVING 50 TO 80 MM
OF TOTAL ACCUMULATED RAINFALL FROM TODAY INTO EARLY SATURDAY.

ALAMO (WPC)
CLARKE (CINWS)
























$$