TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
105 PM EDT TUE APR 30 2024

FORECAST BULLETIN 30 APR 2024 AT 1700 UTC: THE MJO CONTINUES TO
FAVOR CONVERGENT IN THE UPPER LEVELS THROUGH THE FORECAST CYCLE.
UNDER THIS PATTERN...EXPECT AREAS OF POTENTIALLY HEAVY
PRECIPITATION TO REMAIN MOSTLY DISCRETE IN EXTENSION.

A CELL OF THE SUBEQUITORIAL RIDGE CONTINUES TO LIMIT THE
PREGRESSION OF MID TO UPPER LEVEL TROUGHS IN MEXICO. FURTHER
EAST... THE PRESISTENCE OF THE RIDGE WILL SUPPORT THE
AMPLIFICATION OF A MID-UPPER TROUGH OVER THE CARIBBEAN. A POLAR
TROUGH MOVES OVER THE SOUTHEAST USA BY TUESDAY EVENING...
RESULTING IN A DEEPENING OF THE PREXISTING TROUGH. BY WEDNESDAY
MORNING... A WEAK MID-UPPER SHORTWAVE TROUGH DEVELOPS AND MOVES
OVER SE BAHAMAS AND HISPANIOLA. MODELS CONTINUE TO STRUGGLE
RESOLVING THE EVOLUTION AND AS SUCH THERE ARE SLIGHT DISAGREEMENTS
WITH THE SHAPE AND LOCATION OF THE TROUGH AXIS.BY TUESDAY EVENING
A STATIONARY FRONT IS FORECASTED TO EXTENDS FROM 20N 60W TO
NORTH/CENTRAL CUBA WTIH PRECIPITATBLE WATER VALUES IN EXCESS OF
50MM. THE FRONT IS EXPECTED TO MEANDER IN THE GENERAL VICINITY OF
THE GREATER ANTILLES...GRADUALLY DISSIPATING THROUGH WEDNESDAY AND
THURSDAY. INTERRACTIONS WITH THE UPPER LEVEL TROUGH WILL SUPPORT
THE FORMATION OF A FRONTAL WAVE NORTH OF THE PUERTO RICO BY
THURSDAY EVENING WHILE THE FRONT LOSES DEFINITION IN AREAS TO THE
WEST.

IN TERMS OF PRECIPITATION...ON TUESDAY EXPECT MAXIMA OF 20-45MM IN
NORTHEAST CUBA...WHILE CENTRAL CUBA CAN EXPECT MAXIMA OF 15-20MM.
THE BAHAMAS...HISPANIOLA...AND JAMAICA...CAN EXPECT MAXIMA OF
20-35MM. THE AFOREMENTIONED REGIONS ARE EXPECTED TO SEE SLIGHT
RISK OF SEVERE/SQUALLY WEATHER. PUERTO RICO CAN EXPECT MAXIMA OF
20-35MM. ON WEDNESDAY...AN INCREASE IN PRECIPITATION IS EXPECTED
WITH THE ENHANCEMENT OF THE MID TO UPPER LEVEL SHORT WAVE TROUGH
REACHING THE SOUTHERN BAHAMAS/TURKS AND CAICOS...AND NORTHERN
HISPANIOLA. THEY CAN EXPECT MAXIMA OF 30-60MM WITH A MARGINAL RISK
OF SEVERE/SQUALLY WEATHER. EASTERN CUBA CAN ALSO EXPECT A MARGINAL
RISK OF SEVERE WEATHER...WITH MAXIMA OF 20-45MM. JAMAICA CAN
EXPECT SIMILAR AMOUNTS. PUERTO RICO AND SOUTHWESTERN HISPANIOLA
CAN EXPECT MAXIMA OF 20-35MM. BY THURSDAY...THE UPPER LEVEL TROUGH
PROPAGATES TO THE EAST...AND ITS CONVERGENT SIDE IS LOCATED OVER
THE NORTHERN CARIBBEAN...AS SUCH A DECREASE IN PRECIPITATION
TOTALS IS FORECAST. IN NORTHERN DOMINICAN REPUBLIC...EXPECT MAXIMA
OF 20-45MM...WITH A SLIGHT RISK OF SEVERE WEATHER. ELSEWHERE IN
THE GREATER ANTILLES...AND NORTHERN LESSER ANTILLES...EXPECT
GENERALIZED MAXIMA OF 15-25MM.

SEASONAL CONVECTION IN NORTHERN SOUTH AMERICA IS CLUSTERING
GENERALLY ALONG THE ITCZ/NET AND TROUGHS PROPAGATING IN THE
TRADES. THE LARGEST ACCUMULATIONS ARE EXPECTED IN COLOMBIA...WHERE
ENHANCED MOISTURE CONVERGENCE IS EXPECTED THROUGH THE FORECAST
CYCLE. OF RELEVANCE...EXPECT AN INCREASING TREND IN WESTERN
COLOMBIA THROUGH WEDNESDAY/THURSDAY...GIVEN INCREASING
ONSHORE/WESTERLY WINDS AND THE ARRIVAL OF A DISSIPATING EASTERLY
WAVE IN COLOMBIA.

CLARKE/LEDESMA/ACOSTA...WPC (USA)