393
FXCA20 KWBC 301755
PMDCA
TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
155 PM EDT MON MAR 30 2026
FORECAST BULLETIN 30 MARCH 2026 AT 1800 UTC:
MEXICO AND NORTH CENTRAL AMERICA...
A DEEP UPPER LEVEL TROUGH EXTENDS OVER MUCH OF WESTERN MEXICO ON
MONDAY MORNING, AS THE DIVERGENT SIDE OF THE TROUGH REMAINS OVER
MUCH OF WEST AND CENTRAL MEXICO THROUGHOUT THE DAY ON MONDAY. TO
ITS EAST, RIDGING OVER CENTRAL AMERICA EXTENDS INTO THE WESTERN
CARIBBEAN, WHILE THE SUBTROPICAL JET STREAM FAVORS DIVERGENCE
ALOFT BETWEEN THESE UPPER LEVEL SYSTEMS, PRIMARILY OVER SOUTHERN
MEXICO, THE YUCATAN PENINSULA, AND GUATEMALA ON MONDAY. THE UPPER
LEVEL SYSTEMS ARE BEING REFLECTED IN THE MID-LEVELS, AS A TROUGH
WITH MULTIPLE TROUGH AXES REMAINS OVER MUCH OF MEXICO AND IT
INTERACTS WITH RIDGING OVER THE YUCATAN PENINSULA AND INTO CENTRAL
AMERICA THROUGHOUT MONDAY INTO TUESDAY. IN THE LOWER LEVELS, THE
TRADE WINDS ARE GENERALLY COMING FROM THE EAST OVER THE CARIBBEAN
SEA, WITH A FEW MOIST PLUMES EMBEDDED IN THE TRADES THAT ARE
EXPECTED TO REACH THE EASTERN COASTS OF THE REGION BY THE
AFTERNOON HOURS ON MONDAY, FAVORING LIGHT TO MODERATE SHOWERS,
PARTICULARLY IN THE YUCATAN PENINSULA AND EXTENDING FROM BELIZE
THROUGH NICARAGUA. IN WESTERN MEXICO, WESTERLY FLOW IN ASSOCIATION
WITH THE UPPER LEVEL TROUGH BRINGS LIGHT LEVELS OF MOIST FLOW
ALONG THE WESTERN COAST OF MEXICO, WHICH WILL UNDERGO OROGRAPHIC
LIFT AS IT INTERACTS WITH THE SIERRA MADRE OCCIDENTAL AND INTO THE
SIERRA MADRE DEL SUR, FAVORING LIGHT TO MODERATE PRECIPITATION
TOTALS ON MONDAY. ON TUESDAY, THE UPPER LEVEL TROUGH PROPAGATES
EASTWARD, WHERE ITS BASE IS EXPECTED IN SOUTHERN MEXICO BY TUESDAY
EVENING, WITH ITS DIVERGENT SIDE CONTINUING FROM SOUTHERN MEXICO,
THROUGH THE YUCATAN PENINSULA, AND NORTHERN CENTRAL AMERICA. AS
THIS TROUGH HEADS EASTWARD, FEW SHORTWAVE TROUGHS IN THE MID-LEVEL
ALSO EXTEND OVER SOUTHERN MEXICO, FAVORING LIFT AND INSTABILITY
FROM SOUTHERN VERACRUZ/OAXACA INTO GUATEMALA AND THE SOUTHERN
YUCATAN PENINSULA. EXPECT THE REGION TO SEE A RISK FOR SEVERE
THUNDERSTORMS, PARTICULARLY ON TUESDAY EVENING INTO THE EARLY
HOURS OF WEDNESDAY. IN TERMS OF PRECIPITATION TOTALS, MOISTURE
CONTINUES TO ADVECT INTO THE REGION AS MOIST PLUMES ENTER ALONG
THE TRADE WINDS. THE AMOUNT OF PRECIPITABLE WATER IS EXPECTED TO
REMAIN BELOW 50MM THROUGH THE DAY AND LIGHT TO MODERATE TOTALS ARE
EXPECTED FROM SOUTH VERACRUZ/NORTH OAXACA THROUGH CENTRAL
GUATEMALA. ON WEDNESDAY, THE UPPER LEVEL TROUGH REACHES THE
YUCATAN PENINSULA, WITH ITS BASE OVER SOUTHERN MEXICO AND NORTHERN
CENTRAL AMERICA. AS ITS DIVERGENT SIDE ENTERS THE REGION, THE
TROUGH BECOMES LESS POSITIVE, THE COOLER MID-LEVEL TEMPERATURES
DECREASE IN NORTHERN CENTRAL AMERICA, AND WITH THE REGION
BEGINNING TO TRANSITION OUT OF THE DRY SEASON, EXPECT THE RISK OF
SEVERE WEATHER TO INCREASE FROM THE EASTERN YUCATAN PENINSULA
THROUGH BELIZE, GUATEMALA, AND EL SALVADOR. AN INCREASE IN
MOISTURE ON WEDNESDAY WILL FAVOR MODERATE TO LOCALIZED HEAVIER
PRECIPITATION TOTALS ON WEDNESDAY INTO EARLY THURSDAY.
SOUTHERN CENTRAL AMERICA...
THE PREVAILING PATTERN IN THE REGION IS MID TO UPPER LEVEL RIDGING
THAT EXTENDS FROM THE EAST PACIFIC OCEAN THAT EXTENDS INTO THE
WESTERN CARIBBEAN. THIS IS EXPECTED TO FAVOR DRIER CONDITIONS OVER
THE REGION WITH THE PRESENCE OF INVERSION CAPS IN THE LOW TO MID
LEVELS OVER THE NEXT THREE DAYS. THIS WILL INHIBIT THE POTENTIAL
FOR DEEP CONVECTION AND LIMIT THE DAILY TOTAL PRECIPITATION VALUES
FROM LIGHT TO MODERATE TOTALS, ESPECIALLY DUE TO THE LEVELS OF
AVAILABLE MOISTURE THAT IS ADVECTED INTO THE REGION. MONDAY AND
WEDNESDAY ARE EXPECTED TO HAVE LOWER VALUES, WHILE TUESDAY IS
EXPECTED TO SEE THE PRECIPITABLE WATER VALUE EXCEEDING 50MM ENTER
COSTA RICA AND WEST PANAMA.
CARIBBEAN...
ON MONDAY, THE SUBTROPICAL JET IS LOCATED OVER THE NORTHERN
CARIBBEAN, MARKING THE BASE OF A BROAD UPPER TROUGH OVER
HISPANIOLA AND PUERTO RICO/VI ON MONDAY MORNING. IN THE
MID-LEVELS, A MORE DISORGANIZED PATTERN IS PRESENT, BUT A
GENERALIZED RIDGING IS EXPECTED OVER THE WESTERN CARIBBEAN, WHILE
ELONGATED TROUGHING EXTENDS OVER MOST OF THE GREATER ANTILLES AND
THE LEEWARD ISLANDS BY THE EVENING ON MONDAY. THIS PATTERN IS
FAVORING DRIER CONDITIONS WITH VARIOUS TRADE WIND INVERSION CAPS
THAT WILL LIMIT THE DEVELOPMENT OF DEEP CONVECTION. THE LACK OF
LARGE AMOUNTS OF AVAILABLE MOISTURE WILL ALSO FAVOR LIGHT
PRECIPITATION ON MONDAY. SIMILAR CONDITIONS ARE EXPECTED ON
TUESDAY, WHILE AN UPPER LEVEL TROUGH BEGINS TO APPROACH THE WEST
CARIBBEAN FROM MEXICO BY THE EVENING HOURS OF TUESDAY. SIMILAR
PRECIPITATION TOTALS ARE EXPECTED OVER THE REGION ON TUESDAY. BY
WEDNESDAY, THE DIVERGENCE ASSOCIATED WITH THE APPROACHING UPPER
LEVEL TROUGH WILL REACH WESTERN CUBA, AND FAVOR A SLIGHT CHANCE OF
SEVERE WEATHER. THE AMOUNT OF AVAILABLE MOISTURE WILL REMAIN LOW,
OVER MUCH OF THE CARIBBEAN, AND THUS LIGHT PRECIPITATION TOTALS
ARE EXPECTED OVER MUCH OF THE REGION ON WEDNESDAY.
NORTH SOUTH AMERICA...
OVER THE REGION, THE PRESENCE OF A PROPAGATING ATMOSPHERIC KELVIN
WAVE IS FAVORING UPPER LEVEL DIVERGENT CONDITIONS THROUGHOUT THE
TROPICAL REGIONS OF SOUTH AMERICA. MUCH OF THE CONVECTION THAT IS
PRESENT ON MONDAY CAN BE ATTRIBUTED TO LOW LEVEL MOISTURE
CONVERGENCE ALONG TROUGHING THAT ARE TRAVELING THE TRADE WINDS
OVER MUCH OF VENEZUELA, THE GUIANAS, AND THE NORTHERN AMAZON
BASIN. THESE TROUGHS ARE SUPPORTED BY THE DIVERGENCE ALOFT FOR
DEEP CONVECTION, AS WELL AS WITH THE PRESENCE OF PRECIPITABLE
WATER VALUES EXCEEDING 55MM THROUGHOUT THE AMAZON BASIN. WITH
THESE AREAS OF DEEP CONVECTION, EXPECT WIDESPREAD REGION OF
MODERATE TO LOCALLY HEAVY PRECIPITATION OVER THE AMAZON BASIN,
INTO SOUTH VENEZUELA. ON TUESDAY, A PROMINENT PROPAGATING TROUGH
IN THE LOWER LEVELS ENTERS THE WESTERN AMAZON BASIN, WHERE IT WILL
FAVOR HEAVY PRECIPITATION FROM SOUTH COLOMBIA, INTO NORTH PERU AND
INTO AMAZONAS-BRASIL. UPPER LEVEL CONDITIONS WILL CONTINUE TO
VENTILATE THE REGION AND PROVIDE THE DIVERGENCE FOR DEEP
CONVECTION. BY WEDNESDAY, NEW MOIST LOW LEVEL TROUGHS HAVE ENTERED
THE EAST AMAZON BASIN, WHERE EXPECT THEY INTERACT WITH THE BASE OF
AN UPPER LEVEL TROUGH THAT EXTENDS FROM THE SOUTH-CENTRAL BRASIL
REGION. THIS REGION IS EXPECTED TO INTERACT WITH THE BOLIVIAN
HIGH, WHICH WILL BE AN AREA OF DIFFLUENCE AND VENTILATION FOR DEEP
CONVECTION IN THE REGION. EXPECT MODERATE TO HEAVY PRECIPITATION
IN THE EASTERN AMAZON BASIN ON WEDNESDAY.
CASTELLANOS...(WPC)
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page