TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
138 PM EDT TUE MAY 21 2024

FORECAST BULLETIN 21 MAY 2024 AT 1735 UTC:

THE SYSTEM OF CONCERN IS A ROBUST UPPER TROUGH THAT HAS DEEPENED
ACROSS THE NORTHWEST BAHAMAS/CENTRAL CUBA INTO PANAMA/NORTHWEST
COLOMBIA. THIS TROUGH IS INTERACTING WITH THE ITCZ AND WITH THE
PANAMANIAN LOW...AND ITS DRAWING BOTH SYSTEMS NORTHWARD.
FURTHERMORE...THE DIVERGENT TIER OF THE UPPER TROUGH IS LOWERING
THE PRESSURES IN THE NORTH-CENTRAL CARIBBEAN...WHICH FAVORING THE
DEVELOPMENT OF INDUCED TROUGHS IN THE LOW-LEVELS...AND IS BUILDING
A MOIST POOL OF PRECIPITABLE WATER VALUES IN THE 50-60MM RANGE.
THIS IS SETTING UP AN ENVIRONMENT FAVORABLE FOR EXCESSIVE
PRECIPITATION PARTICULARLY ACROSS HISPANIOLA AND ACROSS PUERTO
RICO TO A LESSER EXTENT. ANOTHER REGION OF CONCERN IS PANAMA...FAR
SOUTHERN COSTA RICA AND NORTHWEST COLOMBIA. FURTHERMORE...NOTE
THAT THE POTENT UPPER TROUGH IS PROVIDING AN APPRIPRIATE
ENVIRONMENT FOR SEVERE/SQUALLY CONVECTION IN CUBA AND JAMAICA
EARLY IN THE CYCLE.

ON TUESDAY...EXPECT THE HEAVIEST PRECIPITATION FOCUSING IN WEST
PANAMA/SOUTH COSTA RICA WHERE AFTERNOON/EVENING CONVECTION WILL
LIKELY FAVOR 20-40MM/DAY AND ISOLATED MAXIMA OF 50-100MM. LOCALLY
HEAVY RAIN IS EXPECTED AS WELL IN NORTHWEST COLOMBIA WHERE MAXIMA
WILL LIKELY REACH 35-70MM. IN CUBA AND JAMAICA...EXPECT MAXIMA IN
THE 15-35MM/DAY RANGE WITH A RISK FOR SEVERE CONVECTION. SIMILAR
AMOUNTS ARE EXPECTED IN THE WESTERN DOMINICAN REPUBLIC AND IN
CENTRAL AND NORTHWEST HAITI. IN THE CENTRAL BAHAMAS EXPECT MAXIMA
OF 15MM. ON WEDNESDAY...EXPECT A PEAK IN ACCUMULATIONS IN THE
DOMININICAN REPUBLIC...WHERE AMOUNTS ARE FORECAST IN THE
20-40MM/DAY RANGE AND MAXIMA OF 75-125MM. THIS INCLUDES A RISK FOR
MCS FORMATION IN SOUTHEASTERN PORTIONS OF THE ISLAND. IN THE
HAITIAN PENINSULA EXPECT 15-30MM/DAY AND MAXIMA OF 40-80MM. IN
PUERTO RICO EXPECT MAXIMA OF 20-45MM. IN CUBA...EXPECT MAXIMA OF
15-30MM/DAY WITH A CONTINUED RISK FOR SEVERE CONVECTION DUE TO
INSTABILITY ASSOCIATED WITH THE UPPER TROUGH. IN NORTHEAST JAMAICA
EXPECT MAXIMA OF 15-20MM WITH A MARGINAL RISK FOR SEVERITY. ALSO
ON WEDNESDAY...EXPECT MAXIMA IN THE 35-70MM/DAY RANGE IN SOUTHWEST
PANAMA AND IN EASTERN PANAMA/NORTHWEST COLOMBIA. ON
THURSDAY...EXPECT THE HEAVIEST ACCUMULATIONS TO CLUSTER IN
SOUTHEAST HISPANIOLA...WHERE EXPECT AMOUNTS OF 15-30MM/DAY AND
MAXIMA OF 50-100MM. IN THE HAITIAN PENINSULA AND NORTHEAST/CENTRAL
HISPANIOLA EXPECT 15-20MM/DAY AND MAXIMA OF 35-70MM. IN NORTHWEST
HISPANIOLA EXPECT MAXIMA OF 20-45MM. ALSO ON
THURSDAY...SOUTHWESTERLY LOW-LEVEL FLOW IN PANAMA/NORTHWEST
COLOMBIA WILL LIKELY ENHANCE PRECIPITATION TO FAVOR MAXIMA OF
35-70MM.

IN MEXICO...DIURNAL CONVECTION IS GRADUALLY ACTIVATING. EXPECT
MOST OF THE DIURNAL THUNDERSTORMS TO FLARE UP ALONG THE SIERRA
MADRE ORIENTAL AND THE EJE VOLCANICO TRANSVERSAL CENTRAL. IN AN
INCREASING TREND...EXPECT MAXIMA TO INCREASE TO 15-30MM IN THE EJE
VOLCANICO TRANSVERSAL CENTRAL ON THURSDAY EVENING.

ALSO OF INTEREST...THE FIRST TROPICAL WAVE OF THE SEASON IS
FORECAST TO ARRIVE IN THE GUIANAS EARLY ON THURSDAY. BY THURSDAY
EVENING IT IS FORECAST ACROSS SURINAME...WHERE EXPECT ACCUMULATION
OF 10-15MM/DAY AND MAXIMA OF 20-45MM.

GALVEZ (WPC) / CLARKE (CINWS) / ACOSTA (WPC) / LEDESMA (WPC)