329
FXCA20 KWBC 151853
PMDCA
TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
253 PM EDT WED OCT 15 2025
FORECAST BULLETIN 15 OCTOBER 2025 AT 1900 UTC:
THE BAHAMAS AND CARIBBEAN:
A COLD FRONT CURRENTLY EXTENDING ACROSS SOUTHERN BAHAMAS AND
NORTHERN CUBA WILL CONTINUE TO GENERATE MOST RAINFALL ACTIVITY
ACROSS THE CARIBBEAN FOR THE FORECAST PERIOD. FROM TODAY INTO
THURSDAY, HEAVY RAINFALL IS EXPECTED OVER HISPANIOLA, AS THE COLD
FRONT MOVES TO THE SOUTH, AND THE DIVERGENT SIDE OF A VERTICALLY
STACKED UPPER LEVEL TROUGH WILL BE OVER THE REGION. THE COLD FRONT
MAY CONTINUE TO ENHANCE PRECIPITATION IN THE EASTERN CARIBBEAN,
INCLUDING THE HISPANIOLA AND THE LESSER ANTILLES FROM THURSDAY
THROUGH FRIDAY. HOWEVER, THERE IS SOME UNCERTAINTY REGARDING THE
LOCATION OF THE HEAVIEST RAINFALL. THE ECMWF MODEL SUGGESTS THE
COLD FRONT BEING FURTHER SOUTH, HAVING MORE IMPACT OVER THE
LEEWARD ISLAND, WHILE THE GFS KEEPS MOST PRECIPITATION ASSOCIATED
WITH THE FRONT FURTHER NORTH AND OFFSHORE. REGARDLESS OF THIS,
MOISTURE ADVECTION AND LOW-LEVEL CONFLUENCE OVER THE EASTERN
GREATER ANTILLES AND THE LESSER ANTILLES IS EXPECTED.THE FRONT MAY
START DISSIPATING FROM FRIDAY INTO SATURDAY, BUT WILL CONTINUE
BRINGING PRECIPITATION OVER JAMAICA, HISPANIOLA AND PUERTO RICO,
WITH LOW-LEVEL MOISTURE CONVERGENCE BEING ENHANCED IN THE REGION.
A SLIGHT RISK OF SEVERE WEATHER EXISTS FOR THE LESSER ANTILLES
FROM FRIDAY THROUGH SATURDAY
MEXICO AND CENTRAL AMERICA:
CONDITIONS OVER MEXICO ARE EXPECTED TO REMAIN SIMILAR OVER THE
NEXT THREE DAYS. MOST OF THE PRECIPITATION WILL BE ASSOCIATED WITH
DIURNAL HEATING AND LOCAL EFFECTS. AN UPPER LEVEL TROUGH THAT IS
ALSO REFLECTED IN THE MID LEVELS WILL BE OVER VERACRUZ TODAY, AND
IS EXPECTED TO MOVE NORTH TOMORROW. HOWEVER, LIMITED PRECIPITABLE
WATER AND MORE STABLE CONDITIONS AT LOWER LEVELS WILL LIMIT THE
PRECIPITATION ACTIVITY OVER THE REGION. AFTER THIS, AN UPPER LEVEL
RIDGE WILL MOVE FROM THE GULF INTO SOUTHEASTERN MEXICO.
ADDITIONAL SIGNIFICANT PRECIPITATION IS EXPECTED OVER THE
SOUTHWESTERN COAST OF MEXICO, AND PORTIONS OF GUATEMALA OVER THE
NEXT THREE DAYS, DUE TO A LOW PRESSURE SYSTEM THAT IS CURRENTLY
BEING MONITORED BY THE NATIONAL HURRICANE CENTER, WHICH HAS A 60%
CHANCE OF TROPICAL CYCLONE FORMATION IN THE NEXT SEVEN DAYS.
ALTHOUGH THE MODELS SUGGEST THAT MOST PRECIPITATION WILL REMAIN
OFFSHORE, DAILY ACCUMULATIONS OF 20-35MM ARE EXPECTED IN THE AREA.
AN AREA OF INTEREST FROM TODAY THROUGH THURSDAY IS SOUTHWESTERN
HONDURAS AND NORTHWESTERN NICARAGUA, WITH TOTAL VALUES OF RAINFALL
REACHING 25-50MM. THIS IS LINKED TO THE PROXIMITY OF THE MONSOON
TROUGH TO THE AREA, AN INCREASE IN MOISTURE AVAILABILITY,
ENHANCEMENT IN THE LOW-LEVEL MOISTURE FLUX CONVERGENCE, THE
PRESENCE OF A SHORTWAVE TROUGH AT MID LEVELS, AND SPEED DIVERGENCE
AT UPPER LEVELS. PRECIPITATION DUE TO THE PRESENCE OF THE MONSOON
TROUGH WILL CONTINUE THROUGH SATURDAY OVER THE PACIFIC COAST OF
CENTRAL AMERICA, PARTICULARLY FROM GUATEMALA INTO NICARAGUA.
HEAVY RAINFALL IS EXPECTED OVER THE NEXT THREE DAYS OVER COSTA
RICA. THE MAIN DRIVERS OF PRECIPITATION WILL BE THE MONSOON
TROUGH, HIGH PRECIPITABLE WATER AND THE DEVELOPMENT OF LOW-LEVEL
CIRCULATION WIND PATTERN OVER THE CARIBBEAN ENHANCING FLOW
ONSHORE. SUPPORT FROM MID- TO UPPER-LEVELS IS ALSO EXPECTED WITH
THE PRESENCE OF A MID-LEVEL TROUGH AND A WEAK UPPER LEVEL TROUGH
OVER THE REGION.
TROPICAL SOUTH AMERICA:
IN SOUTH AMERICA PRECIPITATION IS EXPECTED TO BE MOSTLY DUE TO
DIURNAL HEATING AND LOCAL EFFECTS. FOR THE NEXT THREE DAYS HEAVY
RAINFALL IS EXPECTED OVER THE WESTERN COAST OF COLOMBIA WITH
SATURATED FLOW COMING FROM THE EASTERN PACIFIC ENHANCING LOW LEVEL
MOISTURE CONVERGENCE. TODAY INTO THURSDAY, HEAVY RAINFALL IS
EXPECTED OVER WESTERN VENEZUELA AND EASTERN COLOMBIA IN THE
CARIBBEAN REGION, AS A LOW LEVEL TROUGH IS ENHANCING MOISTURE
ADVECTION IN THE REGION AND A MID-LEVEL TROUGH WILL FURTHER
SUPPORT THE DEVELOPMENT OF CONVECTION IN THE AREA. OVER THE
WESTERN AMAZON REGION MOISTURE ADVECTION AND CONVECTIVE INDUCED
TROUGHS ARE EXPECTED TO BRING THUNDERSTORMS AND HEAVY RAINFALL
PARTICULARLY FROM TODAY INTO FRIDAY.
POSITIONS OF TROPICAL/EASTERLY WAVES INITIALIZED AT 12 UTC
TYP SOF INIT 16/00 16/12 17/00 17/12 18/00 18/12 19/00
TW 15N 26W 30W 33W 37W 41W 44W 48W 51W
FOR THE LATEST AVAILABLE CHARTS PLEASE VISIT:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/INTERNATIONAL/CRB_DAY1-3.SHTML
RIVERA-TORRES...(WPC)
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page