835
AXNT20 KNHC 021818
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1815 UTC THU OCT 2 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
1530 UTC.
..SPECIAL FEATURES
ATLANTIC GALE WARNING:
IMELDA HAS BECOME A STRONG EXTRA-TROPICAL CYCLONE AND IS LOCATED
NEAR 33.2N 59.5W OR 275 NM ENE OF BERMUDA AT 02/1500Z. THE
ESTIMATED MINIMUM CENTRAL PRESSURE IS 980 MB. IMELDA IS MOVING ENE
AT 25 KT AND THE MAXIMUM SUSTAINED WINDS ARE 65 KT WITH GUSTS TO
80 KT. SCATTERED MODERATE CONVECTION IS SEEN MAINLY UP TO 200 NM
FROM THE CENTER AT THE NORTHEAST QUADRANT. NEAR-GALE TO GALE-FORCE
SE TO NW WINDS WITH SEAS AT 14 TO 22 FT ARE FOUND SOUTH OF IMELDA
FROM 26N TO 31N BETWEEN 56W AND 65W. A GENERAL ENE TO NE MOTION IS
EXPECTED WITH IMELDA THROUGH SATURDAY. A SLOW WEAKENING TREND IS
FORECAST BUT IMELDA WILL REMAIN A LARGE AND POWERFUL EXTRA-
TROPICAL CYCLONE ACROSS THE NORTH ATLANTIC FOR THE NEXT FEW DAYS.
THIS WILL CAUSE THE NEAR-GALE TO GALE-FORCE WINDS AND VERY ROUGH
TO HIGH SEAS TO ALSO SHIFT NORTHEASTWARD THROUGH FRIDAY.
PLEASE READ THE LATEST 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 MORE
INFORMATION.
FOR THE LAST PUBLIC ADVISORY AND FORECAST/ADVISORY ISSUED BY THE
NATIONAL HURRICANE CENTER ON EXTRA-TROPICAL CYCLONE IMELDA, PLEASE
VISIT HTTPS://WWW.NHC.NOAA.GOV/GRAPHICS_AT4.SHTML?START#CONTENTS
FOR MORE DETAILS.
..TROPICAL WAVES
A FAR EASTERN ATLANTIC TROPICAL WAVE HAS BEEN RELOCATED TO NEAR
31W FROM 19N SOUTHWARD, AND MOVING WEST AT 15 KT. VERY DRY AIR AT
LOW AND MID LEVELS IS HINDERING ANY SIGNIFICANT CONVECTION.
A CENTRAL ATLANTIC TROPICAL WAVE IS NEAR 56W FROM 18N SOUTHWARD,
AND MOVING WEST AT 10 TO 15 KT. THE LACK OF MOISTURE AT THE LOWER
PARTS OF THE ATMOSPHERE IS PROHIBITING CONVECTION.
..MONSOON TROUGH/ITCZ
A MONSOON TROUGH ENTERS THE ATLANTIC ALONG THE SENEGAL COAST NEAR
THE SALOUM DELTA NATIONAL PARK, THEN EXTENDS WEST-SOUTHWESTWARD
ACROSS 09N30W TO 05N43W. AN ITCZ CONTINUES WESTWARD FROM 05N43W TO
NEAR THE COASTAL BORDER OF SURINAME AND FRENCH GUIANA. SCATTERED
MODERATE CONVECTION IS OBSERVED NEAR THE TROUGH BETWEEN 20W AND
26W, AND FARTHER WEST BETWEEN 36W AND 43W. SCATTERED MODERATE TO
ISOLATED STRONG CONVECTION IS FOUND SOUTH OF THE TROUGH FROM 04N
TO 08N BETWEEN 40W AND THE SIERRA LEON-LIBERIA COAST. SIMILAR
CONVECTION IS ALSO PRESENT UP TO 200 NM NORTH AND 130 NM SOUTH OF
THE ITCZ BETWEEN 43W AND 50W.
AIDED BY AN UPPER-LEVEL TROUGH IN THE VICINITY, THE EASTERN END OF
THE EAST PACIFIC MONSOON TROUGH IS CREATING SCATTERED HEAVY
SHOWERS AND ISOLATED STRONG THUNDERSTORMS ACROSS THE SOUTHWESTERN
AND SOUTH-CENTRAL CARIBBEAN BASIN.
..GULF OF AMERICA
A COUPLE OF SURFACE TROUGHS ARE GENERATING SCATTERED MODERATE TO
ISOLATED STRONG CONVECTION FROM THE BAY OF CAMPECHE EASTWARD TO
NORTH OF THE YUCATAN PENINSULA AND CHANNEL, AND ISOLATED
THUNDERSTORMS ACROSS THE EASTERN GULF. MODERATE TO FRESH WITH
LOCALLY STRONG ENE WINDS AND SEAS AT 4 TO 6 FT DOMINATE THE
NORTHEASTERN GULF. MODERATE TO LOCALLY FRESH NE WINDS AND 2 TO 4
FT SEAS ARE NOTED AT THE WESTERN BAY OF CAMPECHE. LIGHT TO GENTLE
WINDS AND 1 TO 2 FT SEAS ARE EVIDENT ACROSS THE FLORIDA STRAITS,
EASTERN BAY OF CAMPECHE. AND NEAR THE YUCATAN CHANNEL. GENTLE TO
MODERATE NE TO SW WINDS AND SEAS OF 1 TO 4 FT PREVAIL FOR THE REST
OF THE GULF.
FOR THE FORECAST, BUILDING HIGH PRESSURE OVER THE CENTRAL AND
EASTERN UNITED STATES WILL DOMINATE THE GULF WATERS THROUGH THE
END OF THE WEEK. FRESH TO STRONG NW WINDS WILL PULSE OFF VERACRUZ
TONIGHT AND FRI. MEANWHILE, THE PRESSURE GRADIENT BETWEEN THE
AFOREMENTIONED RIDGE AND A DEVELOPING LOW PRESSURE FORECAST TO
MOVE ACROSS THE FLORIDA PENINSULA INTO THE GULF OF AMERICA WILL
LEAD TO FRESH TO STRONG E WINDS AND ROUGH SEAS IN THE
NORTHEASTERN GULF TONIGHT, EXPANDING INTO THE NORTH-CENTRAL AND
NORTHWESTERN GULF FRI THROUGH SAT NIGHT. SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS CAN ALSO BE EXPECTED IN THESE AREAS. WINDS
AND SEAS WILL DIMINISH SUN WHEN THE LOW PRESSURE LIFT NORTH AND
OUT OF THE GULF.
..CARIBBEAN SEA
AN UPPER-LEVEL TROUGH EXTENDING SOUTHWESTWARD FROM NEAR PUERTO
RICO TO PANAMA IS ENHANCING ISOLATED THUNDERSTORMS ACROSS THE LEE
OF CUBA AND NEAR THE WINDWARD PASSAGE AND HISPANIOLA. REFER TO
THE MONSOON TROUGH/ITCZ SECTION FOR ADDITIONAL CONVECTION IN THE
CARIBBEAN SEA. A WEAK RIDGE IS PROVIDING MODERATE WITH LOCALLY
FRESH NE TO E WINDS AND 3 TO 5 FT SEAS AT THE SOUTH-CENTRAL BASIN.
LIGHT TO GENTLE WINDS AND SEAS OF 1 TO 3 FT PREVAIL ELSEWHERE IN
THE CARIBBEAN SEA.
FOR THE FORECAST, THE WEAK RIDGE WILL SUPPORT MAINLY MODERATE OR
LIGHTER TRADE WINDS AND SLIGHT TO MODERATE SEAS. MEANWHILE,
NORTHERLY SWELL GENERATED BY POST-TROPICAL CYCLONE IMELDA WILL
REACH THE PASSAGES OF THE NORTHEASTERN CARIBBEAN, ALLOWING ROUGH
SEAS FRI THROUGH EARLY NEXT WEEK.
..ATLANTIC OCEAN
PLEASE READ THE SPECIAL FEATURES SECTION AT THE VERY BEGINNING ON
EXTRA-TROPICAL CYCLONE IMELDA IN NORTH ATLANTIC, AND A GALE
WARNING IN THE WESTERN ATLANTIC.
A FRONTAL TROUGH CURVES SOUTHWESTWARD FROM NEAR IMELDA ACROSS
31N60W TO NEAR THE NORTHWEST BAHAMAS, SCATTERED TO NUMEROUS HEAVY
SHOWERS AND ISOLATED THUNDERSTORMS ARE NOTED NEAR AND UP TO 145
NM SOUTHEAST OF THIS FEATURE. FARTHER SOUTHEAST, TWO SURFACE
TROUGHS ARE PRODUCING SCATTERED SHOWERS FROM 14N TO 24N BETWEEN
40W AND 50W. REFER TO THE MONSOON TROUGH/ITCZ SECTION AT THE
BEGINNING FOR ADDITIONAL WEATHER IN THE ATLANTIC.
OUTSIDE THE GALE WARNING AREA, FRESH TO STRONG NE TO SE TO SW
WINDS AND SEAS OF 8 TO 13 FT ARE EVIDENT NORTH OF 25N AND WEST OF
48W. TO THE EAST, GENTLE TO MODERATE NE TO S-SW WINDS WITH 6 TO 7
FT SEAS EXIST NORTH OF 16N BETWEEN 35W AND 50W. FROM 16N TO 25N
BETWEEN 50W AND THE SOUTHEAST BAHAMAS/LEEWARD ISLANDS, LIGHT TO
GENTLE WINDS AND SEAS OF 4 TO 5 FT ARE PRESENT. FOR THE REMAINDER
OF THE ATLANTIC WEST OF 35W, GENTLE TO MODERATE WITH LOCALLY FRESH
SOUTHERLY WINDS AND 6 TO 8 FT SEAS IN MIXED MODERATE SWELLS
PREVAIL.
FOR THE FORECAST WEST OF 55W, AS EXTRA-TROPICAL CYCLONE IMELDA
CONTINUES TO MOVE AWAY FARTHER NORTH OF 31N, A RIDGE WILL BUILD
WESTWARD ACROSS THE WESTERN ATLANTIC. LONG-PERIOD NORTHERLY SWELL
GENERATED BY FORMER HURRICANE HUMBERTO AND HURRICANE IMELDA WILL
CONTINUE TO AFFECT JUST ABOUT THE ENTIRE WESTERN ATLANTIC THROUGH
EARLY NEXT WEEK. NEAR-GALE TO GALE-FORCE WINDS WILL SHIFT
EASTWARD NORTH OF 29N AND EAST OF 65W THROUGH LATE TONIGHT.
MEANWHILE, AN AREA OF LOW PRESSURE MAY FORM ALONG A REMNANT
FRONTAL BOUNDARY NEAR THE NORTHWEST BAHAMAS AND SOUTHERN FLORIDA
OVER THE NEXT COUPLE OF DAYS. ANY ADDITIONAL DEVELOPMENT IS
EXPECTED TO BE SLOW TO OCCUR AS THE SYSTEM MOVES NORTHWESTWARD
ACROSS THE FLORIDA PENINSULA AND INTO THE GULF OF AMERICA. THE
PRESSURE GRADIENT BETWEEN THIS SYSTEM AND A BUILDING RIDGE OVER
THE EASTERN UNITED STATES WILL FORCE FRESH TO STRONG E WINDS
ACROSS THE WATERS OFF NORTHEASTERN FLORIDA AND THE NORTHWEST
BAHAMAS TODAY THROUGH THE WEEKEND.
CHAN
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