496
AXNT20 KNHC 041822
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1815 UTC SAT OCT 4 2025
TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA, CENTRAL AMERICA
GULF OF AMERICA, CARIBBEAN SEA, NORTHERN SECTIONS OF SOUTH
AMERICA, AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 31N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY, WEATHER OBSERVATIONS, RADAR AND METEOROLOGICAL ANALYSIS.
BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1500 UTC.
..SPECIAL FEATURES
SIGNIFICANT SWELL EVENT OVER THE WESTERN AND CENTRAL ATLANTIC:
LARGE NORTHERLY SWELL GENERATED BY HURRICANE FORCE WINDS
ASSOCIATED WITH PREVIOUS TROPICAL CYCLONES IMELDA AND HUMBERTO IN
THE NORTHERN ATLANTIC CONTINUE TO PROPAGATE SOUTH OF 31N INTO THE
CENTRAL ATLANTIC. AS INDICATED BY RECENT SATELLITE DERIVED SEA
HEIGHTS, THIS SWELL IS CREATING SEAS OF 12 TO 16 FT FROM 22N TO
31N BETWEEN 43W AND 65W. THIS SWELL WILL GRADUALLY SHIFT
NORTHEASTWARD THIS WEEKEND, ALLOWING SEAS IN THE CENTRAL ATLANTIC
TO SLOWLY SUBSIDE, AND DROP BELOW 12 FT SUN MORNING. IN ADDITION,
THIS SWELL EVENT WILL ALSO SUSTAIN DANGEROUS SURF CONDITIONS,
SIGNIFICANT BEACH EROSION AND PROBABLE LOCAL COASTAL INUNDATION
ALONG THE EAST-FACING SHORES OF GEORGIA AND FLORIDA, THE NORTH
AND EAST-FACING SHORES OF THE BAHAMAS, AND THE NORTH-FACING
SHORES ACROSS HISPANIOLA, PUERTO RICO, AND THE VIRGIN AND LEEWARD
ISLANDS. REFER TO YOUR LOCAL WEATHER AGENCIES FOR THE LATEST
STATEMENTS.
PLEASE READ THE LATEST NWS HIGH SEAS AND OFFSHORE WATERS FORECASTS
ISSUED BY THE NATIONAL HURRICANE CENTER AT WEBSITES
HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFAT2.SHTML AND
HTTPS://WWW.NHC.NOAA.GOV/MARINE/OFFSHORES.PHP FOR FURTHER
DETAILS.
..TROPICAL WAVES
A FAR EASTERN ATLANTIC TROPICAL WAVE IS JUST EAST OF THE CABO
VERDE ISLANDS NEAR 21W FROM 17N SOUTHWARD. IT IS MOVING WEST AT
10 TO 15 KT. NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION IS
SEEN FROM 04N TO 08N BETWEEN 20W AND 28W. SCATTERED MODERATE
CONVECTION IS PRESENT FARTHER NORTH FROM 08N TO 13N BETWEEN 25W
AND 30W. GRADUAL DEVELOPMENT IS POSSIBLE OVER THE NEXT SEVERAL
DAYS AND A TROPICAL DEPRESSION COULD FORM DURING THE SECOND HALF
OF NEXT WEEK. THERE IS A MEDIUM CHANCE OF TROPICAL DEVELOPMENT
WITHIN THE NEXT 2 TO 7 DAYS.
A CENTRAL ATLANTIC TROPICAL WAVE IS NEAR 41W FROM 20N SOUTHWARD,
AND MOVING WEST AT 5 TO 10 KT. A VERY DRY AIR MASS AT LOW TO MID
LEVELS ARE PROHIBITING SIGNIFICANT CONVECTION NEAR THIS WAVE.
ANOTHER TROPICAL WAVE IS EAST OF THE LESSER ANTILLES NEAR 56W
FROM 20N SOUTHWARD, AND MOVING WEST AT 5 TO 10 KT. WIDELY
SCATTERED MODERATE CONVECTION IS NOTED FROM 16N TO 18N BETWEEN
52W AND 56W.
..MONSOON TROUGH/ITCZ
A MONSOON TROUGH ENTERS THE ATLANTIC OCEAN ALONG THE COASTAL
BORDER OF SENEGAL AND GUNIA-BISSAU, THEN CURVES SOUTHWESTWARD TO
09N31W. AN ITCZ CONTINUES WESTWARD FROM 09N31W TO 11N48W.
SCATTERED MODERATE CONVECTION IS PRESENT UP TO 85 NM ALONG EITHER
SIDE OF THE ITCZ WEST OF 39W. OTHER THAN THE CONVECTION RELATED TO
TO THE TROPICAL WAVE MENTIONED ABOVE, THERE IS NO SIGNIFICANT
CONVECTION NEAR THE MONSOON TROUGH.
AIDED BY A ROBUST UPPER-LEVEL TROUGH IN THE VICINITY, THE EASTERN
END OF THE EAST PACIFIC MONSOON TROUGH IS TRIGGERING NUMEROUS
HEAVY SHOWERS AND ISOLATED STRONG THUNDERSTORMS AT THE
SOUTHWESTERN CARIBBEAN SEA, INCLUDING COASTAL WATERS OF NICARAGUA,
COSTA RICA, PANAMA AND NORTHWESTERN COLOMBIA.
..GULF OF AMERICA
A NEWLY FORMED STATIONARY FRONT MEANDERS WEST-NORTHWESTWARD FROM A
1010 MB LOW AT THE CENTRAL BAHAMAS ACROSS THE FLORIDA STRAITS TO
ANOTHER 1010 MB LOW AT THE NORTHWESTERN GULF. SCATTERED MODERATE
CONVECTION IS FLARING UP NEAR AND UP TO 100 NM NORTH OF THIS
BOUNDARY. A SURFACE TROUGH IS CAUSING ISOLATED THUNDERSTORMS AT
THE CENTRAL BAY OF CAMPECHE. MODERATE TO FRESH WITH LOCALLY STRONG
EASTERLY WINDS AND SEAS OF 6 TO 9 FT ARE PRESENT NORTH OF THE
STATIONARY FRONT AND LOW. MODERATE TO FRESH NNW WINDS AND 4 TO 6
FT SEAS EXIST OFFSHORE FROM VERA CRUZ, MEXICO. OTHERWISE, LIGHT TO
GENTLE WINDS AND SEAS AT 2 TO 4 FT PREVAIL FOR THE REST OF THE
GULF.
FOR THE FORECAST, FRESH TO LOCALLY STRONG WINDS AND ROUGH SEAS
NORTH OF THE STATIONARY FRONT WILL PERSIST THROUGH SUN MORNING.
THE FRONT WILL LIFT NORTHWARD ON SUN, ALLOWING FOR WINDS AND SEAS
TO SLOWLY DIMINISH ACROSS THE NORTHERN GULF. ELSEWHERE, FRESH NW
WINDS WILL PULSE OFFSHORE OF VERACRUZ THROUGH THIS EVENING.
LOOKING AHEAD, MODERATE E TO SE WINDS AND SLIGHT TO MODERATE SEAS
ARE EXPECTED OVER MUCH OF THE GULF EARLY NEXT WEEK, WITH LOCALLY
FRESH WINDS POSSIBLE IN THE NORTHEASTERN GULF.
..CARIBBEAN SEA
MODEST CONVERGENT TRADE WINDS ARE PRODUCING WIDELY SCATTERED
CONVECTION ACROSS THE NORTHWESTERN BASIN, INCLUDING THE LEE OF
CUBA AND GULF OF HONDURAS. AN BROAD UPPER-LEVEL LOW OVER
HISPANIOLA IS GENERATING ISOLATED THUNDERSTORMS AT THE EASTERN
BASIN, INCLUDING PUERTO RICO AND THE VIRGIN ISLANDS. REFER TO THE
MONSOON TROUGH/ITCZ SECTION ABOVE FOR ADDITIONAL CONVECTION IN
THE CARIBBEAN SEA. WEAK PRESSURE GRADIENT IS ALLOWING GENTLE TO
MODERATE E TO SE WINDS AND SEAS AT 3 TO 5 FT TO DOMINATE THE
SOUTH-CENTRAL BASIN. LIGHT TO GENTLE WINDS EXIST ELSEWHERE IN THE
CARIBBEAN SEA, WHILE 4 TO 6 FT SEAS IN MODERATE NORTHERLY SWELLS
ARE PERSIST IN THE EASTERN BASIN, 1 TO 3 FT SEAS EXIST ELSEWHERE
IN THE BASIN.
FOR THE FORECAST, GENTLE TO MODERATE TRADE WINDS WILL PREVAIL OVER
MOST OF THE CARIBBEAN SEA INTO NEXT WEEK AS A WEAK PRESSURE
GRADIENT PERSISTS ACROSS THE REGION. LARGE N TO NE SWELL,
GENERATED BY PREVIOUS TROPICAL CYCLONES IMELDA AND HUMBERTO,
WILL CONTINUE TO PRODUCE ROUGH SEAS IN THE ATLANTIC PASSAGES AND
OVER THE ATLANTIC WATERS EAST OF THE LESSER ANTILLES INTO SUN
NIGHT. SEAS WILL SLOWLY SUBSIDE EARLY NEXT WEEK. LOOKING AHEAD,
MODERATE TO OCCASIONALLY FRESH E TO SE WINDS WILL PULSE IN THE
GULF OF HONDURAS SUN NIGHT INTO EARLY NEXT WEEK. LOOKING AHEAD, A
TROPICAL WAVE IS OFFSHORE OF AFRICA AND INDUCING ACTIVE CONVECTION
THERE. THE WAVE IS FORECAST TO INTERACT WITH ANOTHER DISTURBANCE
OVER THE EASTERN TROPICAL ATLANTIC, AND THEN CONTINUE TO MOVE
WESTWARD AFTER THAT.
..ATLANTIC OCEAN
PLEASE READ THE SPECIAL FEATURES SECTION AT THE VERY BEGINNING
ON LARGE NORTHERLY SWELL EVENT.
A COLD FRONT RUNS SOUTHWESTWARD FROM EXTRA-TROPICAL CYCLONE EMELDA
AT THE NORTHERN ATLANTIC ACROSS 31N43W TO 28N47W, THEN CONTINUES
WESTWARD AS A STATIONARY FRONT TO A 1010 MB LOW AT THE CENTRAL
BAHAMAS. WIDELY SCATTERED TO SCATTERED MODERATE CONVECTION AND
ISOLATED THUNDERSTORMS ARE OCCURRING UP TO 100 NM NORTH, AND 50 NM
SOUTH OF THE STATIONARY FRONT. AT THE EASTERN ATLANTIC, A
PRONOUNCED UPPER-LEVEL LOW IS CAUSING ISOLATED STRONG
THUNDERSTORMS FROM 25N TO 28N BETWEEN 21W AND 30W. REFER TO THE
MONSOON TROUGH/ITCZ AND TROPICAL WAVES SECTIONS FOR ADDITIONAL
CONVECTION IN THE ATLANTIC BASIN.
OTHER THAN THE VERY ROUGH SEAS MENTIONED IN THE SPECIAL FEATURES
SECTION, FRESH TO LOCALLY STRONG NE TO E WINDS AND 8 TO 11 FT SEAS
ARE PRESENT NORTH OF 22N BETWEEN 50W AND THE FLORIDA/SOUTHERN
GEORGIA COAST. FARTHER EAST, GENTLE TO MODERATE E TO SE WINDS AND
SEAS AT 7 TO 11 FT ARE PRESENT NORTH OF 12N BETWEEN 35W AND 50W.
FROM 12N TO 22N BETWEEN 50W AND THE BAHAMAS/LESSER ANTILLES,
GENTLE TO MODERATE SE TO S WINDS AND 6 TO 10 FT SEAS ARE NOTED.
FOR THE REMAINDER OF THE ATLANTIC BASIN WEST OF 35W, GENTLE TO
MODERATE WITH LOCALLY FRESH SE TO SW WINDS AND 6 TO 8 FT SEAS
PREVAIL.
FOR THE FORECAST WEST OF 55W, SEAS WILL SLOWLY SUBSIDE FROM NORTH
TO SOUTH OVER THE CENTRAL ATLANTIC EARLY NEXT WEEK, WITH ROUGH
SEAS PERSISTING NORTH OF 24N AND WEST OF 60W THROUGH MIDWEEK.
FRESH TO STRONG NE TO E WINDS WILL PREVAIL NORTH OF A STATIONARY
FRONT, EXTENDING FROM THE CENTRAL ATLANTIC THROUGH THE FLORIDA
STRAITS, THROUGH AT LEAST TUE BEFORE WINDS SLOWLY DIMINISH
MIDWEEK. LOOKING AHEAD, A TROPICAL WAVE BETWEEN THE WEST COAST OF
AFRICA AND CABO VERDE ISLANDS COULD SEE GRADUAL DEVELOPMENT OVER
THE NEXT FEW DAYS.
CHAN
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