Prognostic Meteorological Discussion
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FXCA20 KWBC 141857
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
257 PM EDT FRI JUN 14 2024

FORECAST BULLETIN 14 JUN 2024 AT 1845 UTC:

THE MAIN STORY OF THE DAY CONTINUES TO BE THE DEVELOPING CENTRAL
AMERICAN GYRE...WHICH WILL CAUSE SIGNIFICANT RAINFALL ACROSS
CENTRAL AMERICA INTO SOUTHERN MEXICO OVER THE NEXT SEVERAL DAYS.
THE MODEL GUIDANCE HAS A 72-HOUR TOTAL ACCUMULATED RAINFALL TOTALS
THAT RANGE BETWEEN 250 AND 400MM FROM TODAY INTO MONDAY FOR THE
PACIFIC COAST OF WESTERN PANAMA TO EL SALVADOR. WITH COSTA RICA
RECEIVING THE HIGHEST AMOUNTS...BUT THERE IS SOME UNCERTAINTY ON
THE EXACT LOCATION OF THE ISOLATED HIGHEST AMOUNTS...SO IT IS
WORTH KNOWING THAT THERE WILL BE PERSISTENT FLOW INTO THE PACIFIC
COAST OF CENTRAL AMERICA FROM THE MONSOON TROUGH...WHICH IS
CARRYING HIGHER MOISTURE THAN NORMAL AND WILL THEN CAUSE THE
SIGNIFICANT RAINFALL EXPECTED THIS WEEKEND AND BEYOND. THIS EVENT
WILL BE PROLONGED INTO NEXT WEEK AND COULD CAUSE VERY HAZARDOUS
CONDITIONS FOR PORTIONS OF CENTRAL AMERICA. THE HIGHEST AMOUNTS OF
RAIN THIS WEEKEND...AS MENTIONED ABOVE...IS EXPECTED TO BE IN AND
AROUND COSTA RICA...BUT BY THE MIDDLE TO THE LATTER PARTS OF NEXT
WEEK...THE HIGHEST AMOUNTS WOULD BE OVER THE PACIFIC COAST OF
SOUTHWESTERN NICARAGUA...PORTIONS OF HONDURAS...EL
SALVADOR...GUATEMALA AND INTO CHIAPAS OF MEXICO. THE MODEL
GUIDANCE IS SUGGESTING UPWARDS OF 500 - 700MM OF RAIN FOR THE
ENTIRE EVENT BEFORE IT MAY START TO SETTLE DOWN BY THE END OF NEXT
WEEK.

FOR TODAY INTO SATURDAY MORNING...WESTERN PANAMA INTO COSTA RICA
ARE FORECAST TO OBSERVE RAINFALL MAXIMA UP TO 150MM...WHILE OTHER
AREAS OF CENTRAL AMERICA HAVE FORECAST MAXIMA RANGING FROM AROUND
30MM TO 60MM.  NORTHERN SOUTH AMERICA WILL HAVE A FEW TROPICAL
WAVES AND TROUGHS MOVING THROUGH...CAUSING INTERMITTENT PERIODS OF
SHOWERS AND THUNDERSTORMS ACROSS THE AREA. THE RAINFALL MAXIMA
WILL BE HIGHEST ACROSS THE GUIANAS INTO EASTERN VENEZUELA...AS
WELL AS WESTERN COLOMBIA WITH TOTALS NEAR 60 AND 100MM...WHILE
OTHER AREAS WILL OBSERVE MAXIMA OF 25 TO 45MM. THE CARIBBEAN
REGION WILL BE RELATIVELY QUIET AS DRIER AIR WITH SAHARAN DUST
WILL START MOVING IN...BUT THE EXCEPTION WILL BE WESTERN CUBA AND
THE EASTERN SHORE OF THE YUCATAN PENINSULA...WHERE MAX VALUES UP
TO 60MM COULD BE OBSERVED.

FOR SATURDAY INTO SUNDAY...THE HEAVY RAINFALL EXPECTED OVER
CENTRAL AMERICA WILL START TO EXPAND TO THE NORTH. COSTA RICA AND
PANAMA ARE STILL EXPECTED TO RECEIVE THE HIGHEST RAINFALL MAXIMA
OF THE AREA...WITH TOTALS NEAR 75-150MM. HOWEVER...THE REST OF
CENTRAL AMERICA...ESPECIALLY THE PACIFIC SIDE INTO PORTIONS OF
CHIAPAS...COULD OBSERVE RAINFALL MAXIMA BETWEEN 40-80MM. NORTHERN
SOUTH AMERICA WILL CONTINUE HAVING THE TROPICAL WAVES AND
TROUGHS...CAUSING DAILY RAINFALL MAXIMA BETWEEN 40 AND 80MM IN
SOME AREAS. THE CARIBBEAN CONTINUES TO BE RELATIVELY
QUIET...THOUGH THE YUCATAN PENINSULA CONTINUES TO HAVE AREAS WITH
SIGNIFICANT RAINFALL...POSSIBLY REACHING TOTALS NEAR 40-80MM.

SUNDAY INTO MONDAY WOULD BE THE DAY WHERE THE VERY HEAVY RAIN
STARTS TO MOVE TO EL SALVADOR AND GUATEMALA IN CENTRAL AMERICA.
ALTHOUGH PORTIONS OF COSTA RICA ARE STILL FORECAST TO OBSERVE
MAXIMA UP TO 100MM...PORTIONS OF NICARAGUA INTO GUATEMALA AND EL
SALVADOR COULD OBSERVE RAINFALL MAXIMA BETWEEN 100 AND 200MM IN A
24-HOUR PERIOD...WHICH IS VERY SIGNIFICANT FOR THAT AREA. OTHER
AREAS IN CENTRAL TO NORTHERN GUATEMALA...AS WELL AS THE YUCATAN
PENINSULA AND CHIAPAS COULD OBSERVE SHOWERS AND
THUNDERSTORMS...WITH RAINFALL TOTALS REACHING NEAR 50MM. NORTHERN
SOUTH AMERICA START TO OBSERVE LESS RAINFALL FOR THAT
PERIOD...WITH ONLY A FEW AREAS OF WESTERN VENEZUELA AND
SOUTHWESTERN COLOMBIA AND ECUADOR HAVING UP TO 50MM OF RAINFALL
FORECAST...WHILE THE REST OF THE AREA IS FORECAST RAINFALL MAXIMA
OF AROUND 35MM OR LESS. ONCE AGAIN...THE CARIBBEAN IS EXPECTED TO
REMAIN RELATIVELY QUIET EVEN THOUGH THERE MAY BE A SFC TROUGH NEAR
HISPANIOLA...THE DRY AIR AND SAHARAN DUST WILL LIKELY LIMIT THE
SHOWER ACTIVITY ACROSS THE AREA...AND THUS A MAX RAINFALL OF 10MM
ARE FORECAST ACROSS THE ANTILLES.

CURRENTLY THERE IS A STRONG SFC HIGH PRESSURE ACROSS THE CENTRAL
ATLANTIC CAUSING EASTERLY WINDS ACROSS THE ATLANTIC INTO THE
CARIBBEAN. THERE IS ALSO A SFC TROUGH ACROSS THE WESTERN TROPICAL
ATLANTIC AND ANOTHER ACROSS THE GULF OF MEXICO. SEVERAL TROPICAL
WAVES WILL BE MOVING THROUGH THE REGION AS WELL...THOUGH MOSTLY
SOUTH OF 13N...AND MOST OF THEM WOULD DISSIPATE BY THE TIME THEY
REACH CENTRAL AMERICA AS THEY WOULD BE ABSORBED BY THE SFC TROUGH
AND EVENTUAL CENTRAL AMERICAN GYRE.

IN SUMMARY...THE LATEST GUIDANCE CONTINUES TO SUGGEST THAT THE SFC
TROUGH ACROSS THE GULF OF MEXICO...AND THE POSITIONING OF THE
MONSOON TROUGH IN THE PACIFIC WILL CAUSE A VERY MOIST ONSHORE FLOW
INTO CENTRAL AMERICA FOR THE NEXT SEVERAL DAYS AS A CENTRAL
AMERICAN GYRE DEVELOPS. THE ABOVE NORMAL MOISTURE THAT WILL BE
PRESENT IN THE ONSHORE FLOW TOWARDS CENTRAL AMERICA WILL COMBINE
WITH THE UP-SLOPE EFFECT OF CERTAIN PORTIONS OF CENTRAL
AMERICA...CAUSING PERSISTENT RAINFALL DEVELOPMENT.

WE WILL CONTINUE TO MONITOR THE SITUATION IN CENTRAL AMERICA
CLOSELY.


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
























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