TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
303 PM EDT FRI MAY 17 2024

FORECAST BULLETIN 17 MAY 2024 AT 1900 UTC:

NOTE: THE NATIONAL HURRICANE CENTER IS MONITORING TWO AREAS
POSSIBLE TROPICAL CYCLONE DEVELOPMENT OVER THE NEXT SEVERAL DAYS
IN THE EASTERN PACIFIC. THE LATEST OUTLOOK SUGGESTS A LOW CHANCE
OF TROPICAL CYCLONE FORMATION THROUGH 7 DAYS. PLEASE CHECK THE NHC
WEBSITE FOR UPDATES.

ACROSS THE EASTERN CENTRAL ATLANTIC THERE IS A SFC HIGH THAT IS
CAUSING EASTERLY WINDS THROUGH THE TROPICAL ATLANTIC INTO THE
CARIBBEAN. THERE IS ALSO A SFC LOW ACROSS THE WESTERN ATLANTIC
THAT IS SLOWLY MOVING NORTHEAST. HOWEVER...ANOTHER SFC LOW
PRESSURE WILL DEVELOP ACROSS THE WESTERN ATLANTIC...NEAR BERMUDA
BY LATE SUNDAY INTO MONDAY. ACROSS THE EASTERN PACIFIC...THERE ARE
A COUPLE OF SFC LOWS THAT COULD SPIN OF THE MONSOON TROUGH THIS
WEEKEND.

IN THE MID LEVELS...A HIGH PRESSURE RIDGE WILL DOMINATE MOST OF
THE WESTERN CARIBBEAN AND INTO THE EASTERN MEXICO AND CENTRAL
AMERICA...LIMITING CONVECTION OVER THE AREA FOR MOST OF THE
WEEKEND. THERE IS A BROAD TROUGH ACROSS THE WESTERN ATLANTIC INTO
THE EASTERN CARIBBEAN...AND IT IS MOVING EAST...SO THE EASTERN
CARIBBEAN ISLANDS ARE IN THE SUBSIDENT SIDE OF THAT TROUGH. BY
SUNDAY...A MID LEVEL TROUGH WILL HAVE ITS BASE OVER THE NORTHERN
GULF OF MEXICO AS IT MOVES EAST. THE POSITIONING OF THIS MID LEVEL
TROUGH WILL ENHANCE INSTABILITY OVER THE NORTHEASTERN GULF OF
MEXICO INTO THE NORTHERN BAHAMAS BY MONDAY. THE UPPER LEVELS ALSO
HAVE A TROUGH EXTENDING INTO THE EASTERN CARIBBEAN...AND A RIDGE
OVER THE WESTERN CARIBBEAN INTO EASTERN MEXICO TODAY. ANOTHER
TROUGH WILL MOVE THROUGH THE CARIBBEAN ON SATURDAY INTO
SUNDAY...WITH ITS AXIS OVER HISPANIOLA AND PUERTO RICO. BY
MONDAY...THE AXIS OF THIS UPPER TROUGH WILL BE OVER THE LEEWARD
ISLANDS. A WEAKER UPPER TROUGH WILL DEVELOP OVER THE NORTHERN GULF
OF MEXICO ON SUNDAY. THIS TROUGH WILL MOVE EAST AND WILL BE OVER
THE EASTERN GULF OF MEXICO INTO THE WESTERN ATLANTIC BY VERY EARLY
MONDAY.

ACROSS THE CARIBBEAN...THE RAINFALL AMOUNTS ARE EXPECTED TO BE
SOMEWHAT LIMITED. THE AVAILABLE MOISTURE WILL BE NEAR TO BELOW
NORMAL ACROSS THE CARIBBEAN THIS WEEKEND. THERE IS ALSO SOME
INDICATION THAT SAHARAN DUST PARTICLES COULD MAKE THEIR WAY INTO
THE CARIBBEAN THIS WEEKEND...WHICH WOULD ALSO HELP TO LIMIT THE
CONVECTION OVER THE AREA. FOR THAT REASON...THE MAX RAINFALL
AMOUNTS OVER THE CARIBBEAN NATIONS ARE NOT FORECAST TO SURPASS
25MM AT ANY GIVEN DAY THIS WEEKEND.

THE BAHAMAS WILL ALSO REMAIN FAIRLY QUIET OVER THE WEEKEND...WITH
THE EXCEPTION OF THE NORTHERNMOST ISLANDS. THE NORTHERN BAHAMAS
HAVE A CHANCE OF SHOWERS AND THUNDERSTORMS FOR THE REST OF
TODAY...THEN ON SUNDAY INTO MONDAY. THE AFOREMENTIONED SFC LOW
NEAR BERMUDA WILL PULL SOME MOISTURE FROM THE SOUTH INTO THE
NORTHERN BAHAMAS...WHICH WILL COMBINE WITH THE MID TO UPPER LEVEL
TROUGHS OVER THE AREA...TO CAUSE A CHANCE OF SQUALLY WEATHER AND
POSSIBLE SEVERE THUNDERSTORMS AT SOME POINT LATE SUNDAY INTO
MONDAY.

ACROSS CENTRAL AMERICA...A PATCH OF DRY AIR WILL MOVE NORTHWEST
FROM PANAMA TODAY...INTO NICARAGUA AND HONDURAS BY LATE SATURDAY
INTO SUNDAY. THIS WILL CAUSE A DECREASE IN THE FORECAST RAINFALL
TODAY AND SATURDAY OVER THAT PORTION OF CENTRAL AMERICA. THE
WETTEST PERIOD OVER PANAMA AND COSTA RICA WILL BE FROM SUNDAY INTO
EARLY MONDAY...WHILE TODAY INTO EARLY SATURDAY WILL BE THE WETTEST
DAY FOR NICARAGUA AND HONDURAS...BUT THEN DRYING OUT EACH DAY INTO
MONDAY. ACROSS THE NORTHERN COUNTRIES OF CENTRAL
AMERICA...PARTICULARLY GUATEMALA AND BELIZE...AS WELL AS THE
SOUTHERNMOST SECTIONS OF MEXICO INCLUDING THE CHIAPAS STATE...WILL
HAVE A SIGNIFICANT INFLUX OF MOISTURE FROM SATURDAY INTO
SUNDAY...CAUSING RAINFALL TOTALS THAT COULD HAVE MAX AMOUNTS NEAR
40-80MM...BUT LESSER AMOUNTS OF RAIN ARE FORECAST TODAY AND SUNDAY
INTO MONDAY. 

IN NORTHERN SOUTH AMERICA...MOST OF THE RAINFALL ACROSS THE AREA
WILL BE ALONG THE ITCZ/NET...WITH PEAKS IN MOISTURE CORRELATED TO
EASTERLY WAVES AND SFC TROUGHS. SATURDAY INTO MONDAY APPEARS TO BE
THE PERIOD WITH THE HIGHEST RAINFALL POTENTIAL...POSSIBLY IN PART
NOT ONLY DUE TO THE ABUNDANT MOISTURE...BUT ALSO DUE TO THE
DIVERGENCE AND DIFFLUENCE THAT CAN BE OBSERVED OVER THE AREA AS
THE UPPER TROUGH DIGS INTO THE CARIBBEAN. MAX RAINFALL VALUES
ALONG THE ITCZ/NET AS WELL AS OVER PORTIONS OF VENEZUELA AND
COLOMBIA CAN OBSERVE MAX VALUES BETWEEN 35 AND 80MM ON SATURDAY
INTO SUNDAY...WHILE MAX VALUES GO DOWN TO 30-60MM ON SUNDAY INTO
MONDAY OVER VENEZUELA AND COLOMBIA...LESSER AMOUNTS OF RAIN ARE
FORECAST ELSEWHERE.

ALAMO...WPC (USA)