787  
AXNT20 KNHC 142339  
TWDAT  
 
TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL  
0015 UTC MON DEC 15 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH  
2330 UTC.  
   
..SPECIAL FEATURES
 
 
WESTERN ATLANTIC GALE WARNING: GALE-FORCE NORTHWEST TO NORTH  
WINDS AND ROUGH SEAS OF 10 TO 15 FT (3 TO 4.5 M) IN NORTH SWELL  
ARE EXPECTED OVER SOME PORTIONS OF THE WATERS EAST OF NORTHERN  
FLORIDA THIS EVENING AND INTO MON MORNING IN THE WAKE OF AN  
ARCTIC COLD FRONT THAT HAS RECENTLY MOVED OVER THE WATERS EAST OF  
NORTHEAST FLORIDA ALONG A POSITION FROM NEAR 31N78W TO INLAND  
NORTHERN FLORIDA NEAR SAINT AUGUSTINE. WIDESPREAD STRONG TO NEAR-  
GALE FORCE NORTHERLY WINDS ALONG WITH ROUGH SEAS IN NORTHWEST TO  
NORTH SWELL ARE EXPECTED NORTH AND NORTHEAST OF THE BAHAMAS  
NORTHWARD AND WEST OF A LINE FROM 31N50W TO 22N72W THROUGH EARLY  
ON TUE. THE SWELL WILL REACH THE ISLANDS OF THE NORTHEAST  
CARIBBEAN LATE TUE NIGHT INTO EARLY WED AS IT MERGED WITH EAST  
SWELL. SEAS WILL BEGIN TO GRADUALLY SUBSIDE FROM NW TO SE WED  
THROUGH WED NIGHT. PLEASE READ THE LATEST HIGH SEAS FORECAST  
ISSUED BY THE NATIONAL HURRICANE CENTER AT WEBSITE  
HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFAT2.SHTML FOR MORE  
INFORMATION.  
 
EAST ATLANTIC SIGNIFICANT SWELL EVENT: LARGE, LONG PERIOD NORTH  
TO NORTHEAST SWELL CONTINUES TO AFFECT MOST OF THE EASTERN  
TROPICAL AND SUBTROPICAL ATLANTIC. SEAS 12 FT OR GREATER ARE  
CURRENTLY FROM 10N TO 19N BETWEEN 26W AND 45W, AND FROM 10N TO  
30N EAST OF 26W ALONG WITH PEAK SEAS TO 13 FT (4 M)JUST SOUTHWEST  
OF THE CANARY ISLANDS. THE SWELL DIRECTION IS FROM THE N TO NE  
WINDS AT A PERIOD OF 10-16 SECONDS. WITH PERSISTENT FRESH TO  
STRONG NORTHEAST NORTHEAST TRADE WINDS, THE AREA OF 12 FT (4 M)  
OR GREATER SEAS WILL EXPAND WESTWARD TO NEAR 50W BY EARLY MON  
BEFORE THEY SLOWLY SUBSIDE FROM NE TO SW GOING INTO TUE. FOR  
INFORMATION EAST OF 35W PLEASE READ THE LATEST HIGH SEAS  
FORECAST ISSUED BY METEO-FRANCE AT WEBSITE:  
HTTPS://WWMIWS.WMO.INT/INDEX.PHP/METAREAS/AFFICHE/2. FOR  
INFORMATION WEST OF 35W, PLEASE READ THE LATEST HIGH SEAS  
FORECAST ISSUED BY THE NATIONAL HURRICANE CENTER AT WEBSITE:  
HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFAT2.SHTML.  
   
..MONSOON TROUGH/ITCZ
 
 
THE MONSOON TROUGH AXIS ENTERS THE ATLANTIC NEAR 08N13W, AND  
CONTINUES SOUTHWESTWARD TO 05N19W, WHERE IT TRANSITIONS TO THE  
ITCZ TO 04N30W TO 02N40W AND TO INLAND SOUTH AMERICA NEAR 01N52W.  
NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION IS SEEN WITHIN  
120 NM SOUTH OF THE TROUGH AND ITCZ BETWEEN 16W-22W. SCATTERED  
MODERATE CONVECTION IS WITHIN 120 NM SOUTH OF THE TROUGH BETWEEN  
THE COAST OF AFRICA AND 16W AND WITHIN 30 TO 60 NM OF THE ITCZ  
BETWEEN 22W-27W.  
 
GULF OF AMERICA...  
 
AN ARCTIC COLD FRONT EXTENDS FROM NEAR APALACHICOLA TO THE  
NORTHEAST MEXICO-TEXAS BORDER AS STRONG HIGH PRESSURE BUILDS IN  
OVER THE BASIN BEHIND IT. THE VERY TIGHT PRESSURE GRADIENT  
BETWEEN THE FRONT AND THE HIGH PRESSURE IS BRINGING STRONG TO  
NEAR-GALE FORCE NORTHEAST WINDS, WITH FREQUENT GUSTS TO GALE  
FORCE OVER GULF COASTAL WATERS AND OCCASIONAL GUSTS TO GALE-FORCE  
JUST EAST OF THESE WATERS AS INDICATED IN THE LATEST BUOY  
OBSERVATIONS AND BY A 1620Z ASCAT PASS. SEAS WITH THESE WINDS ARE  
IN THE RANGE 8 TO 11 FT (2.5 TO 3.5 M). SCATTERED SHOWERS AND  
THUNDERSTORMS MOVING SOUTHWARD ARE PRESENT SOUTH OF THE FRONT TO  
NEAR 22N AND WEST OF 96W TO JUST INLAND THE COAST OF MEXICO. THE  
LATEST ASCAT SATELLITE DATA SHOWS GENTLE TO MODERATE NORTH TO  
NORTHEAST WINDS ELSEWHERE ACROSS THE BASIN ALONG WITH SEAS OF 4  
TO 6 FT. LOWER SEAS OF 3 TO 4 FT ARE OVER THE EXTREME EASTERN BAY  
OF CAMPECHE.  
 
FOR THE FORECAST, THE COLD WILL SWEEP ACROSS THE REST OF THE GULF  
REACHING SOUTH OF THE BASIN MON NIGHT. WINDS WILL BECOME FRESH  
TO STRONG, NORTHEAST IN DIRECTION ACROSS JUST ABOUT THE ENTIRE  
GULF ON MON, EXCEPT FOR MOSTLY STRONG NORTHERLY WINDS ALONG THE  
COAST OF MEXICO NEAR TAMPICO AND VERACRUZ. BY LATE MON NIGHT,  
GENTLE TO MODERATE EAST WINDS ARE EXPECTED NORTH OF 26N, AND  
MOSTLY FRESH NORTHEAST TO EAST WINDS ARE EXPECTED SOUTH OF 26N.  
SEAS AT THAT TIME ARE EXPECTED TO BE 5 TO 7 FT, EXCEPT FOR HIGHER  
SEAS OF 6 TO 9 F T IN NORTH TO NORTHEAST SWELL SOUTH OF 26N.  
AFTERWARD, SEAS WILL SLOWLY SUBSIDE DURING THE MIDDLE PORTION OF  
THE WEEK AS HIGH PRESSURE DOMINATES THE REGION.  
 
CARIBBEAN SEA...  
 
ATLANTIC HIGH PRESSURE HAS SHIFTED EASTWARD TO THE CENTRAL  
ATLANTIC. AS AS RESULT, THE TRADE WINDS OVER THE EASTERN  
CARIBBEAN HAVE DIMINISHED TO MODERATE TO FRESH SPEEDS, BUT  
CONTINUE AT FRESH TO STRONG SPEEDS ACROSS THE CENTRAL CARIBBEAN  
WATERS. GENTLE TO MODERATE TRADE WINDS ARE OVER THE WESTERN  
CARIBBEAN. LATEST SATELLITE ALTIMETER DATA PASSES INDICATE SEAS  
OF 5 TO 8 FT OVER MOST OF THE BASIN EAST OF ABOUT 81W, WITH THE  
EXCEPTION OF HIGHER SEAS OF 7 TO 9 FT FROM 11N TO 16N BETWEEN 72W  
AND 80W. LOWER SEAS OF 4 TO 5 FT ARE WEST OF 81W. SEAS MAY BE  
LOCALLY HIGHER IN ATLANTIC PASSAGES OF THE LESSER ANTILLES DUE TO  
ARRIVING EAST SWELL. OTHERWISE, A TROUGH IS ANALYZED OVER THE  
NORTHWESTERN CARIBBEAN ALONG A POSITION FROM NEAR 20N84W TO  
18N86W AND TO NEAR 16N 87W. AN AREA OF SCATTERED TO NUMEROUS  
MODERATE CONVECTION IS EAST OF THE TROUGH FROM 16N TO 18N BETWEEN  
84W AND 86W AS AN UPPER-LEVEL IMPULSE RIDES ALONG A SUBTROPICAL  
JET STREAM PRESENT OVER THE WESTERN CARIBBEAN. ISOLATED SHOWERS  
AND THUNDERSTORMS ARE ELSEWHERE SOUTH OF 19N BETWEEN 80W AND 88W.  
MOSTLY OVERCAST LOW AND MID- LEVEL CLOUDS ARE PRESENT NORTH OF  
16N BETWEEN 78W AND 84W. PATCHES OF LIGHT TO MODERATE RAIN ALONG  
WITH ISOLATED SHOWERS ARE EMBEDDED WITHIN THIS AREA OF  
CLOUDINESS.  
 
FOR THE FORECAST, FRESH TO OCCASIONALLY STRONG TRADE WINDS AND  
MODERATE TO ROUGH SEAS OVER THE CENTRAL CARIBBEAN WILL CONTINUE  
TO DIMINISH AS ATLANTIC HIGH PRESSURE SHIFTS WELL TO THE  
NORTHEAST OF THE REGION. ELSEWHERE, FRESH TO LOCALLY STRONG  
TRADE WINDS AND ROUGH SEAS IN LARGE EAST SWELL WILL PREVAIL OVER  
THE TROPICAL ATLANTIC WATERS, THROUGH THE ATLANTIC PASSAGES AND  
INTO THE EASTERN PART OF THE BASIN THROUGH MON NIGHT. A COLD  
FRONT WILL ENTER THE NORTHWESTERN CARIBBEAN ON MON, FOLLOWED  
BY INCREASING WINDS AND BUILDING SEAS BEHIND THE FRONT. THIS  
FRONT IS EXPECTED TO REACH FROM CENTRAL CUBA TO NORTHERN BELIZE  
TUE MORNING, THEN WILL STALL AND GRADUALLY DISSIPATE THROUGH WED.  
HIGH PRESSURE WILL BUILD OVER THE WESTERN ATLANTIC WED NIGHT  
THROUGH THU NIGHT TO BRING A RETURN TO FRESH TO STRONG TRADES  
ACROSS THE CENTRAL CARIBBEAN.  
 
ATLANTIC OCEAN...  
 
PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION ON  
A GALE WARNING FOR THE WESTERN ATLANTIC WATERS OFFSHORE NORTHERN  
FLORIDA, AND FOR A SIGNIFICANT SWELL EVENT IN THE EASTERN  
ATLANTIC.  
 
AN ARCTIC COLD FRONT IS JUST INLAND THE GEORGIA COAST. A TROUGH  
IS ANALYZED FROM NEAR 31N73W SOUTHWESTWARD TO CENTRAL BAHAMAS AND  
TO THE COAST OF CUBA NEAR 22N78W WHILE AT THE SAME TIME A RATHER  
BROAD UPPER-LEVEL TROUGH IS ADVANCING EASTWARD OVER THE EASTERN  
UNITED STATES. GENTLE TO MODERATE SOUTHEAST TO SOUTH WINDS ARE  
BETWEEN THE TROUGH AND 63W WHILE LIGHT AND VARIABLE WINDS ARE  
WEST OF THE TROUGH, EXCEPT FOR GENTLE TO MODERATE NORTHWEST WINDS  
FROM 27N TO 29N AND MODERATE TO FRESH NORTHWEST WINDS NORTH OF  
29N. SEAS ARE 4 TO 6 FT WEST OF THE TROUGH, EXCEPT FOR LOWER SEAS  
OF 3 TO 4 FT SOUTH OF ABOUT 25N. A WELL PRONOUNCED JET STREAM  
BRANCH ROUNDS THE BASE OF THE TROUGH FROM NEAR 31N79W TO THE  
EASTERN GULF OF AMERICA NEAR 26N87W. ABUNDANT OVERCAST MULTILAYER  
CLOUDINESS IS EVIDENT BETWEEN 67W AND 79W, AND MOSTLY MID TO  
UPPER BROKEN TO OVERCAST CLOUDS SHIFTING EASTWARD ARE NORTH OF  
21N BETWEEN 55W AND 67W. SATELLITE IMAGERY ALSO SHOWS SCATTERED  
TO NUMEROUS SHOWERS AND THUNDERSTORMS NORTH OF 21N BETWEEN 67W  
AND 73W. ISOLATED SHOWERS AND THUNDERSTORMS MOVING NORTHEAST  
AROUND 10 KT ARE NORTH OF 27N BETWEEN 73W AND 78W. ISOLATED  
SHOWERS ARE SOUTH OF 27N BETWEEN 73W AND 79W.  
 
A 1028 MB HIGH CENTER IS ANALYZED AT 31N43W AS A DISSIPATING  
STATIONARY EXTENDS FROM 31N41W TO 31N55W. ISOLATED SHOWERS  
ARE POSSIBLE NORTH OF 30N BETWEEN 35W AND 40W. A TIGHT PRESSURE  
GRADIENT BETWEEN THE HIGH PRESSURE AND RELATIVELY LOWER PRESSURE  
TO ITS SOUTH IS SUSTAINING FRESH TO STRONG TRADE WINDS OVER  
THE WATERS SOUTH OF ABOUT 25N AND EAST OF 62W. SEAS ARE 8 TO 11  
FT WITH THESE TRADE WINDS, EXCEPT AS NOTED ABOVE IN THE SPECIAL  
FEATURES SECTION.  
 
FOR THE FORECAST W OF 55W, THE ABOVE MENTIONED ARCTIC COLD FRONT  
WILL MOVE TO OVER THE FAR NORTHWEST WATERS EAST OF NORTHERN  
FLORIDA EARLY THIS EVENING, FOLLOWED BY STRONG TO NEAR GALE-  
FORCE NORTHERLY WINDS AND RAPIDLY BUILDING SEAS THROUGH  
MON MORNING. GALE-FORCE WINDS ARE EXPECTED BEHIND THE FRONT THIS  
EVENING THROUGH EARLY MON. THE FRONT WILL REACH FROM JUST EAST  
OF BERMUDA TO THE NW BAHAMAS AND TO THE STRAITS OF FLORIDA BY MON  
MORNING, THEN STALL FROM NEAR 29N55W TO THE SOUTHEASTERN BAHAMAS  
AND CENTRAL CUBA BY TUE MORNING. LARGE NORTH SWELL WILL BUILD  
ACROSS THE REGIONAL WATERS BEHIND THE FRONT TONIGHT THROUGH TUE  
BEFORE SUBSIDING.  
 

 
AGUIRRE  
 
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