857
FXCA20 KWBC 211839
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
238 PM EDT FRI JUN 21 2024

FORECAST BULLETIN 21 JUN 2024 AT 1830 UTC:

THE TROPICAL REGION HAS SEVERAL FEATURES THAT COULD CAUSE
SIGNIFICANT RAINFALL IN SOME AREAS. THE MAIN FEATURE TO WATCH IS
AN AREA OF DEEPENING PRESSURE ACROSS THE SOUTHWEST GULF OF
MEXICO...WHICH WILL CAUSE A BROAD CIRCULATION INTO SOUTHERN MEXICO
AND PORTIONS OF CENTRAL AMERICA. ALTHOUGH THIS SYSTEM DOES NOT
LOOK AS STRONG...SIMILAR TO THE CENTRAL AMERICAN GYRE (CAG) THAT
WAS OBSERVED A FEW DAYS AGO...THIS REINFORCEMENT OF THE CAG WILL
CAUSE DEEP TROPICAL MOISTURE TO BE PULLED INTO CENTRAL AMERICA AND
SOUTHERN MEXICO FROM THE PACIFIC. THIS AREA OF LOW
PRESSURE...WHICH THE NATIONAL HURRICANE CENTER IS MONITORING FOR
POSSIBLE TROPICAL CYCLONE DEVELOPMENT...WILL SLOWLY MOVE WEST
ACROSS THE GULF OF MEXICO...AND IS EXPECTED TO MOVE INLAND OVER
EAST-NORTHEAST MEXICO VERY LATE SUNDAY INTO MONDAY. UNDER THIS
PATTERN...AREAS OF CENTRAL AMERICA...SOUTHERN AND EASTERN MEXICO
WILL HAVE SIGNIFICANT RAIN OVER THE NEXT SEVERAL DAYS. THE LATEST
GUIDANCE IS SUGGESTING THAT AS MUCH AS 200MM OF RAIN OR MORE COULD
BE OBSERVED OVER THE NEXT 3 DAYS...WITH SATURDAY BEING THE DAY
WITH HIGHEST RAINFALL OVER NORTHEASTERN MEXICO NEAR THE BOUNDARY
OF VERACRUZ...TAMAULIPAS...AND SAN LUIS POTOSI. TODAY...THE
EASTERN COAST OF MEXICO FROM VERACRUZ TO TAMAULIPAS AND SAN LUIS
POTOSI MAY RECEIVE AS MUCH AS 50MM OF RAIN...THEN NORTHEASTERN
MEXICO COULD OBSERVE OVER 150MM ON SATURDAY...WHILE ISOLATED AREAS
OF SOUTHERN AND EXTREME NORTHERN VERACRUZ COULD OBSERVE UPWARDS OF
60-100MM OR SO ON SUNDAY. IT IS ALSO WORTH NOTING THAT THERE IS AN
UPPER TROUGH ACROSS THE WESTERN GULF OF MEXICO...THAT WILL
CONTINUE MOVING WEST AND IS ENHANCING CONVECTION TO THE SOUTH AND
EAST OF ITS AXIS...WHICH IS OVER AND AROUND THE YUCATAN PENINSULA
AND NEAR THE BOUNDARY OF GUATEMALA AND EL SALVADOR TODAY. FOR THAT
REASON...THE DAY WITH THE HIGHEST RAINFALL OVER NORTHERN CENTRAL
AMERICA IS EXPECTED TO BE TODAY...WITH OVER 75MM OF RAIN IN THE
FORECAST...BUT THE FORECAST 72-HR RAINFALL TOTAL COULD BE OVER
150MM IN ISOLATED AREAS.

ELSEWHERE IN THE REGION...THERE ARE A FEW TROPICAL WAVES THAT WILL
BE MOVING THROUGH...THOUGH MAINLY WILL BE SOUTH OF 15N. THIS MEANS
THAT THE TROPICAL WAVES WILL BE AFFECTING MAINLY NORTHERN SOUTH
AMERICA AND THE SOUTHERN CARIBBEAN. BASED ON THE LATEST
GUIDANCE...PORTIONS OF NORTHERN VENEZUELA INTO WESTERN COLOMBIA
COULD RECEIVE DAILY MAX RAINFALL AMOUNTS OF AROUND 60-80MM AS A
TROPICAL WAVE MOVES THROUGH...WHILE EACH SUBSEQUENT DAY WILL HAVE
LOWER AMOUNTS OF RAIN. FURTHER NORTH...OVER THE GREATER ANTILLES
INTO THE BAHAMAS...THE AVAILABLE MOISTURE WILL IN FACT BE ABOVE
NORMAL...BUT THERE WILL BE A BROAD MID LEVEL HIGH PRESSURE THAT
WILL INHIBIT DEEP CONVECTION TO DEVELOP ACROSS THE ISLANDS. THERE
WILL ALSO BE SOME SAHARAN DUST MOVING IN THIS WEEKEND...WHICH WILL
ALSO WORK TO INHIBIT CONVECTION. THEREFORE...SOME RAIN AND
ISOLATED THUNDERSTORMS WOULD BE EXPECTED ACROSS THE CARIBBEAN
ISLANDS AND THE BAHAMAS...BUT THE AMOUNTS EACH DAY ARE NOT
EXPECTED TO BE PARTICULARLY IMPRESSIVE...WITH MAX DAILY TOTALS OF
AROUND 25-35MM ACROSS ISOLATED AREAS.

IN SUMMARY...THE REINFORCEMENT OF THE CAG WILL BRING ADDITIONAL
RAIN TO PORTIONS OF CENTRAL AMERICA AND MEXICO...THOUGH NOT AS
MUCH AS WE SAW SEVERAL DAYS AGO. THE UPPER TROUGH WILL ENHANCE
PRECIPITATION ACROSS CENTRAL AMERICA TODAY...BUT THE HIGHEST
RAINFALL ACCUMULATIONS OVER NORTHEASTERN MEXICO IS EXPECTED ON
SATURDAY. PASSING TROPICAL WAVES MAY HELP IN THE DEVELOPMENT OF
SHOWERS AND THUNDERSTORMS OVER NORTHERN SOUTH AMERICA THIS
WEEKEND. THE CARIBBEAN ISLANDS AND THE BAHAMAS WILL HAVE SOME RAIN
EACH DAY THIS WEEKEND BUT NOTHING OUT OF THE ORDINARY...WITH THEN
SAHARAN DUST MOVING INTO THE LEEWARDS LATE TONIGHT...REACHING
HISPANIOLA BY SUNDAY.


ALAMO/ACOSTA (WPC)
CLARKE (CINWS)
FERNANDER (BDM)
























$$