TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
148 PM EDT WED JUN 07 2023

FORECAST BULLETIN FROM 07 JUN 2023 AT 1745 UTC: THE MAIN STORY
OVER THE NEXT FEW DAYS IS THE RAINFALL THAT IS EXPECTED OVER
PORTIONS OF NORTHERN CARIBBEAN AND THE BAHAMAS. THIS MULTI-DAY WET
SPELL COULD CAUSE RAINFALL TOTALS THAT COULD REACH 200MM AND EVEN
HIGHER IN ISOLATED SPOTS. IN FACT...SOME HIGH RESOLUTION GUIDANCE
IS SUGGESTING ISOLATED MAXIMA BETWEEN 300 AND 400MM IN PORTIONS OF
CUBA AND BAHAMAS. AN UPPER-LEVEL TROUGH...ALSO REFLECTED IN THE
MID-LEVELS ACROSS THE EASTERN GULF OF MEXICO...WILL CAUSE
INSTABILITY ACROSS PORTIONS OF CUBA...JAMAICA...AND THE BAHAMAS.
THERE WILL ALSO BE AN UPPER-LEVEL JET ASSOCIATED WITH THE
TROUGH...WHICH WILL CAUSE DIVERGENCE ALOFT...SUPPORTING PERSISTENT
SHOWER AND THUNDERSTORM DEVELOPMENT. A SURFACE HIGH PRESSURE
ACROSS THE CENTRAL TROPICAL ATLANTIC AND A SURFACE LOW PRESSURE
ACROSS THE NORTHWESTERN ATLANTIC WILL CAUSE A PERSISTENT SOUTHERLY
WIND FLOW ACROSS THE CARIBBEAN THROUGH THE 3-DAY PERIOD. THIS
SOUTHERLY WIND FLOW WILL DRAG MOISTURE FROM THE SOUTHERN
CARIBBEAN...CAUSING PRECIPITABLE WATER ANOMALIES THAT COULD BE
CLOSE TO OR EVEN OVER 2 STANDARD DEVIATIONS FROM
NORMAL...ESPECIALLY ACROSS CENTRAL CUBA AND CENTRAL BAHAMAS. THE
EGDI ALGORITHM IS SUGGESTING SCATTERED THUNDERSTORMS WITH HEAVY
RAIN THROUGH THE FORECAST PERIOD...WHILE THE GR02T ALGORITHM
(WHICH MEASURES THE SEVERITY AND POTENTIAL OF HAIL) IS SUGGESTING
A MARGINAL RISK FOR SEVERE STORMS. THE 500MB TEMPERATURES ARE
RATHER WARM...SO THE RISK OF SEVERE HAIL IS NOT TOO SIGNIFICANT.
OVERALL...EACH DAY WILL HAVE SIGNIFICANT RAINFALL OVER PORTIONS OF
JAMAICA...CUBA...AND THE BAHAMAS.

ACROSS MEXICO AND CENTRAL AMERICA...TODAY...THE EASTERN YUCATAN
PENINSULA IS FORECAST TO HAVE RAINFALL MAXIMA OF 20-35MM. ACROSS
GUATEMALA AND WESTERN EL SALVADOR...RAINFALL MAXIMA IS FORECAST TO
BE IN THE RANGE OF 20-45MM...WHILE CHIAPAS/OAXACA/VERACRUZ OF
MEXICO...RAINFALL MAXIMA OF 15-25MM ARE EXPECTED. HIGHER AMOUNTS
OF RAIN ARE EXPECTED OVER COSTA RICA DE TO THE PROXIMITY OF A
TROPICAL WAVE WITH ITS AXIS OVER THE PANAMA/COSTA RICA
BORDER...WITH ACCUMULATIONS OF 15-20MM GENERALLY BUT MAXIMA
BETWEEN 25-50MM. HOWEVER...PANAMA COULD OBSERVE 10-15MM WITH
MAXIMA OF 20-35MM. ON THURSDAY...THE TROPICAL WAVE IS EXPECTED TO
HAVE DISSIPATED BUT A SMALL SECTION OF COSTA RICA COULD OBSERVE
RAINFALL MAXIMA BETWEEN 30-60MM...WHILE PANAMA IS FORECAST 05-10MM
WITH MAXIMA UP TO 25MM. THE REST OF CENTRAL AMERICA...THE YUCATAN
PENINSULA...AND SOUTHERN AND CENTRAL MEXICO ARE FORECAST TO
OBSERVE GENERALIZED RAIN BETWEEN 05-15MM WITH ISOLATED MAXIMA
BETWEEN 20-35MM. ON FRIDAY...PORTIONS OF SOUTHERN MEXICO AND THE
YUCATAN PENINSULA IS FORECAST TO HAVE 05-10MM OF RAIN WITH MAXIMA
OF 15-25MM. FROM GUATEMALA TO NICARAGUA AS WELL AS EASTERN
PANAMA...10-15MM WITH MAXIMA OF 20-35MM IS FORECAST. COSTA RICA
WOULD HAVE THE HIGHEST AMOUNTS OF RAIN...WITH 15-20MM OVERALL WITH
MAXIMA OF 25-50MM.

IN TROPICAL SOUTH AMERICA...A SERIES OF TROPICAL WAVES ARE
FORECAST TO PASS OVER THE AREA. THE BELOW CHART PROVIDES
PRECIPITATION.

POSITIONS OF TROPICAL/EASTERLY WAVES INITIALIZED AT 12 UTC
TYPE  SOF INIT 08/00 08/12 09/00 09/12 10/00 10/12 11/00
TW    12N  48W   51W   54W   58W   61W   64W   67W   70W
TW    14N  67W   69W   71W   73W   75W   77W   80W   82W
TW    18N  78W   80W   DISS  ---   ---   ---   ---   ---    

A TROPICAL WAVE IS INITIALIZED AT 48W AND SOUTH OF 12N. IT IS
CURRENTLY OVER OPEN WATERS...BUT WILL ARRIVE AT THE FRENCH
GUIANA/AMAPA-BRASIL ON WEDNESDAY EVENING...WHERE EXPECT MAXIMA OF
15-35MM. ON THURSDAY...THE WAVE IS FORECAST OVER THE
GUYANA...WHERE EXPECT GENERALIZED MAXIMA OF 15-25MM. SIMILAR
AMOUNTS ARE EXPECTED ON FRIDAY OVER EAST VENEZUELA...WHERE THE
WAVE WILL BE LOCATED BY FRIDAY EVENING.

A TROPICAL WAVE IS INITIALIZED AT 67W AND SOUTH OF 14N. ON
WEDNESDAY...THE WAVE AXIS IS EXPECTED OVER WESTERN VENEZUELA/EAST
COLOMBIA. FROM CENTRAL VENEZUELA INTO NORTH AMAZONAS-BRASIL ARE
FORECAST TO OBSERVE RAINFALL MAXIMA OF 20-35MM. ON THURSDAY...THE
WAVE IS FORECAST OVER CENTRAL COLOMBIA...WHERE EXPECT MAXIMA OF
20-45MM. BY FRIDAY...THE IS FORECAST OVER THE DARIEN REGION. MOIST
ONSHORE FLOW FROM THE WEST WILL ENHANCE THE PRECIPITATION OVER THE
PACIFIC BASIN IN COLOMBIA...WHERE EXPECT MAXIMA OF 35-70MM.
NORTHERN COLOMBIA IS FORECAST FOR 20-45MM...WHILE EAST PANAMA MAY
SEE MAXIMA OF 15-25MM.

A TROPICAL WAVE IS INITIALIZED AT 78W AND SOUTH OF 18N. THE WAVE
WILL MOVE WEST TO WESTERN PANAMA BY WEDNESDAY EVENING...CAUSING AN
INCREASE IN RAINFALL OVER COSTA RICA WITH MAXIMA OF
25-50MM...WHILE PANAMA WILL SEE LOWER AMOUNTS OF 20-35MM.
THEREAFTER...THE WAVE LOSES DEFINITION AND DISSIPATES BY THURSDAY.

ALAMO/ACOSTA...WPC (USA)