TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
102 PM EDT FRI AUG 30 2024

FORECAST BULLETIN 30 AUG 2024 AT 17 UTC:

NOTE: A MESOSCALE CONVECTIVE VORTEX HAS DEVELOPED OVER THE BAHAMAS
AS A RESULT BETWEEN THE INTERACTION OF A POTENT UPPER TROUGH AND A
TROPICAL WAVE. ALTHOUGH THIS SYSTEM HAS AN OPEN TROUGH IN THE
LOWER TROPOSPHERE...A CLOSED CIRCULATION IS PRESENT IN THE
MID-TROPOSPHERE...CONSISTENT WITH THE SATELLITE PRESENTATION.
GIVEN THAT THE UPPER TROUGH IS FORECAST TO EVOLVE SLOWLY...EXPECT
LARGE RAINFALL ACCUMULATIONS IN THE BAHAMAS AND PARTS OF CUBA IN
THE NEXT THREE DAYS. THROUGH SATURDAY...EXPECT 20-40MM/DAY AND
MAXIMA OF 75-125M  IN THE NORTHWEST AND CENTRAL BAHAMAS WITH A
RISK FOR SEVERE WEATHER AND MCS. NOTE THAT ISOLATED HIGHER AMOUNTS
ARE ALWAYS POSSIBLE WITH THIS TYPE OF EVOLUTION. IN CENTRAL AND
EASTERN CUBA...EXPECT MAXIMA OF 35-70MM WITH A SLIGHT RISK FOR
SEVERE WEATHER. IN WEST CUBA EXPECT MAXIMA OF 20-40MM. ON
SATURDAY...EXPECT MAXIMA OF 35-70MM AND A RISK FOR HEAVY
THUNDERSTORMS IN THE FAR NORTHWEST BAHAMAS...WHILE IN THE CENTRAL
BAHAMAS EXPECT MAXIMA OF 20-35MM. IN CENTRAL AND WESTERN CUBA
EXPECT MAXIMA OF 20-40MM. ON SUNDAY...EXPECT MAXIMA OF 25-50MM IN
THE FAR NORTHWEST BAHAMAS. IN CUBA...THE ARRIVAL OF A TROPICAL
WAVE WILL FAVOR AN INCREASE TO MAXIMA OF 25-50MM. IN JAMAICA...THE
TROPICAL WAVE WILL FAVOR 10-15MM/DAY AND MAXIMA OF 20-40MM.

WESTERN MEXICO IS EXPECTED TO ACTIVATE DUE THE ORGANIZATION OF AN
UPPER TROUGH LOCATED OVER/WEST OF THE BAJA CALIFORNIA PENINSULA.
INITIALLY...ENHANCED MOISTURE ALONG THE GULF OF CALIFORNIA WILL
STIMULATE DIURNAL CONVECTION FROM NAYARIT/NORTHERN JALISCO INTO
SINALOA. THIS WILL FAVOR 15-20MM/DAY AND MAXIMA OF 30-60MM THROUGH
EARLY SATURDAY. ON SATURDAY...DEVELOPING ONSHORE FLOW IN
JALISCO/NAYARIT WILL FAVOR AN INCREASE TO 15-30MM/DAY AND MAXIMA
OF 40-80MM. IN SINALOA/DURANGO EXPECT MAXIMA OF 25-50MM. AS THE
UPPER TROUGH APPROACHES FROM THE WEST...EXPECT AN INCREASE IN
CHIHUAHUA TO MAXIMA OF 15-30MM. ON SUNDAY...AS THE POSITIVE
INTERACTION BETWEEN THE UPPER TROUGH AND THE MOIST PLUME
PEAKS...EXPECT SCATTERED ACCUMULATIONS OF 15-20MM/DAY AND MAXIMA
OF 35-70MM FROM NAYARIT/ZACATECAS NORTH INTO SOUTHERN CHIHUAHUA
AND NORTHERN SINALOA. IN NORTHERN CHIHUAHUA EXPECT MAXIMA OF
20-40MM.

AN ENHANCED MOIST POOL AND PANAMANIAN LOW CIRCULATIONS WILL
SUSTAIN AN ACTIVE THREE-DAY PERIOD IN SOUTHERN CENTRAL AMERICA. ON
FRIDAY...A MESOSCALE LOW IS PROPAGATING WESTWARD IN AREAS
SOUTHWEST OF COSTA RICA. THIS WILL FAVOR A FEEDER-BAND LIKE
STRUCTURE DEVELOPING ALONG THE PACIFIC BASIN OF COSTA RICA AND FAR
SOUTHWEST PANAMA...TO FAVOR MAXIMA OF 30-60MM. A TROPICAL WAVE IS
ALSO PRESENT...WHICH WILL FAVOR MAXIMA OF 20-45MM ELSEWHERE IN
COSTA RICA...IN SOUTHEAST NICARAGUA AND WEST PANAMA. ON
SATURDAY...TROPICAL WAVE MOISTURE IS FORECAST TO REACH THE GULF OF
FONSECA...WHILE THE ITCZ ORGANIZES ALONG THE CONTINENTAL DIVIDE IN
COSTA RICA. UNDER THIS PATTERN...EXPECT 15-20MM/DAY AND MAXIMA OF
35-70MM FROM WEST PANAMA INTO WEST NICARAGUA/GULF OF FONSECA
REGION. ON SUNDAY...THE TROPICAL WAVE WILL MOVE RAPIDLY WEST TO
ENTER MEXICO. HOWEVER THE LINGERING MOIST PLUME WILL FAVOR
10-15MM/DAY AND MAXIMA OF 20-40MM IN MOST OF NORTHERN CENTRAL
AMERICA. IN SOUTHERN CENTRAL AMERICA...THOUGH...AN APPROACHING
TROPICAL WAVE AND RESTREGHTENING OF THE PANAMANIAN LOW CIRCULATION
WILL LIKELY YIELD TO ANOTHER DAY WITH MODERATE/LOCALLY HEAVY
RAINS. EXPECT 15-30MM/DAY AND MAXIMA OF 40-80MM.

ANOTHER SYSTEM OF INTEREST IS A TROPICAL WAVE CURRENTLY
PROPAGATING ALONG 44-46W. THIS SYSTEM IS BEING MONITORED BY THE
NHC. MODELS CONTINUE STRUGGLING WITH THE EVOLUTION OF THIS WAVE AS
IT ENTERS THE SOUTHEAST CARIBBEAN LATE ON MONDAY.
REGARDLESS...EXPECT MODERATE TO LOCALLY HEAVY PRECIPITATION WITH
THIS SYSTEM EARLY NEXT WEEK. IN THE MEAN TIME...AS THE TROPICAL
WAVE ENTERS GUYANA ON SUNDAY...IT WILL FAVOR MAXIMA OF 20-40MM
SPREADING INTO TRINIDAD AND TOBAGO...WHERE AN ACTIVE ITCZ/MONSOON
TROUGH IS EXPECTED.

LASTLY...PERIODS OF ENHANCED CONVECTION ARE EXPECTED ALONG THE
ITCZ/NET IN NORTHERN SOUTH AMERICA. THE REGION OF LAKE
MARACAIBO/NORTHERN COLOMBIA WILL LIKELY BE THE MOST ACTIVE. THIS
INCLUDES A RISK FOR MCS FORMATION ON SATURDAY AND MAXIMA OF
40-80MM. OTHERWISE...EXPECT GENERALLY MAXIMA IN THE 20-40MM/DAY
RANGE.

JACKMAN...(BMS BARBADOS)
MATHIAS...(CIAARA-MB BRASIL)
FERNANDER...(BDM BAHAMAS)
GALVEZ...(WPC)
TINOCO...(WPC)
ACOSTA...(WPC)