814  
AXNT20 KNHC 210544  
TWDAT  
 
TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL  
0615 UTC SAT MAR 21 2026  
 
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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH  
0540 UTC.  
   
..SPECIAL FEATURES  
 
EAST ATLANTIC LONG-PERIOD N SWELL: VERY LARGE, LONG-PERIOD NORTH  
SWELL GENERATED BY A LARGE FETCH OF GALE-FORCE WINDS IN THE  
NORTHEAST ATLANTIC WILL CONTINUE TO PROPAGATE SOUTHWARD OF 31N  
THROUGH SUN. EXPECT SEAS OF 12-20 FT TONIGHT, SUBSIDING TO 12 TO  
16 FT ON SAT, MAINLY N OF 19N AND EAST OF ABOUT 38W. SEAS OVER  
THESE NORTHEASTERN WATERS WILL GRADUALLY DIMINISH IN AREAL  
COVERAGE WITH THE REMAINING VERY ROUGH SEAS SUBSIDING BELOW 12 FT  
NEAR THE CANARY ISLANDS MON. PLEASE REFER TO THE LATEST HIGH SEAS  
FORECAST ISSUED BY THE NATIONAL HURRICANE CENTER AT WEBSITE  
HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFAT2.SHTML FOR MORE DETAILS.  
   
..MONSOON TROUGH/ITCZ  
 
THE MONSOON TROUGH AXIS ENTERS THE ATLANTIC THROUGH THE COAST OF  
SIERRA LEONE NEAR 07N12W AND CONTINUES SOUTHWESTWARD TO 04N18W,  
WHERE IT TRANSITIONS TO THE ITCZ THAT CONTINUES TO 00N30W TO JUST  
INLAND BRAZIL NEAR 01S44W. SCATTERED MODERATE CONVECTION IS FROM  
00N TO 06N BETWEEN 10W AND 30W. NUMEROUS MODERATE TO STRONG  
CONVECTION IS ELSEWHERE FROM 02S TO 05N BETWEEN 34W AND 51W.  
   
..GULF OF AMERICA  
 
A BASIN-WIDE RIDGE IS CENTERED BY A 1021 MB HIGH LOCATED OVER THE  
NE GULF NEAR 28N86W. THE PRESSURE GRADIENT BETWEEN THIS RIDGE AND  
A COLD FRONT OVER THE CENTRAL CARIBBEAN IS LEADING TO FRESH N TO  
NE WINDS ACROSS THE SE GULF, ALONG WITH SEAS OF 4 TO 7 FT.  
MODERATE OR WEAKER WINDS AND SLIGHT TO MODERATE SEAS ARE  
ELSEWHERE.  
 
FOR THE FORECAST, THE PRESSURE GRADIENT BETWEEN THE RIDGE ACROSS  
THE GULF REGION AND A COLD FRONT OVER THE CENTRAL CARIBBEAN SEA  
WILL CONTINUE TO SUPPORT FRESH NE WINDS AND MODERATE SEAS OVER  
THE SE GULF, INCLUDING THE STRAITS OF FLORIDA, THROUGH TONIGHT.  
MODERATE TO FRESH NE WINDS ARE EXPECTED NIGHTLY, THROUGH THE  
FORECAST PERIOD, ACROSS THE EASTERN BAY OF CAMPECHE DUE TO LOCAL  
EFFECTS ASSOCIATED WITH A TROUGH. ELSEWHERE, MODERATE OR WEAKER  
WINDS, AND SLIGHT TO MODERATE SEAS WILL PREVAIL THROUGH TUE. WINDS  
MAY BRIEFLY INCREASE TO FRESH SPEEDS OVER THE NE GULF LATE TUE  
INTO EARLY WED AS THE PRESSURE GRADIENT TIGHTENS THERE.  
   
..CARIBBEAN SEA  
 
A COLD FRONT EXTENDS FROM WINDWARD PASSAGE TO THE OFFSHORE  
WATERS OF COLOMBIA. MAINLY MODERATE TO FRESH NNE WINDS FOLLOW THE  
FRONT, WITH LOCALLY STRONG WINDS BEING OBSERVED IN THE LEE SIDE OF  
SOUTHERN CUBA AND OFFSHORE NICARAGUA. SEAS ARE MODERATE TO 6 FT  
BEHIND THE FRONT. AHEAD OF THE FRONT, OVER THE EASTERN CARIBBEAN,  
WINDS ARE MODERATE OR WEAKER FROM THE SE AND SEAS ARE SLIGHT TO  
MODERATE.  
 
FOR THE FORECAST, FRESH TO LOCALLY STRONG N WINDS AND MODERATE TO  
ROUGH SEAS WILL CONTINUE BEHIND THE FRONT, WHICH IS FORECAST TO  
DISSIPATE TONIGHT. AFTERWARD, MODERATE TO LOCALLY STRONG NE WINDS  
WILL REMAIN IN THE WESTERN CARIBBEAN, INCLUDING THE LEE SIDE OF  
CUBA AND THE WINDWARD PASSAGE THROUGH EARLY SUN AS HIGH PRESSURE  
DEVELOPS ACROSS THE NORTHERN BAHAMAS IN THE WAKE OF THE FRONT. AS  
THE RIDGE SHIFTS SLIGHTLY EASTWARD, FRESH TO STRONG WINDS AND  
MODERATE TO ROUGH SEAS WILL DEVELOP OFFSHORE COLOMBIA SUN NIGHT  
AND PREVAIL THROUGH WED NIGHT.  
   
..ATLANTIC OCEAN  
 
 
REFER TO THE SPECIAL FEATURES SECTION FOR DETAILS ON LARGE  
NORTHERLY SWELL THAT IS IMPACTING THE FAR NORTHEAST WATERS OF THE  
DISCUSSION AREA.  
 
A COLD FRONT EXTENDS FROM SE OF BERMUDA NEAR 31N64W TO A 1010 MB  
LOW PRESSURE LOCATED NEAR 28N67W TO EASTERN CUBA INTO THE CENTRAL  
CARIBBEAN SEA. A PRE-FRONTAL TROUGH IS PARALLEL TO THE BOUNDARY  
FROM 23N66W ACROSS HISPANIOLA TO 17N74W. SCATTERED HEAVY SHOWERS  
ARE IN THE VICINITY OF THE FRONT BETWEEN 56W AND 75W. THE  
PRESSURE GRADIENT BETWEEN THE FRONT AND HIGH PRESSURE BUILDING  
TOWARD THE REGION FROM THE SE U.S. IS LEADING TO FRESH TO STRONG N  
WINDS AND ROUGH SEAS WEST OF THE FRONT TO ABOUT 77W. AHEAD OF THE  
FRONT TO 56W, WINDS ARE FRESH TO STRONG FROM THE SSW AND SEAS ARE  
ROUGH TO 11 FT.  
 
IN THE EAST ATLANTIC, A DISSIPATING STATIONARY FRONT LIES BETWEEN  
THE CANARY ISLANDS AND THE CAPE VERDE ISLAND. THE PRESSURE  
GRADIENT BETWEEN THE LOW PRESSURE SYSTEM ASSOCIATED WITH THIS  
FRONT AND A STRONG AND BROAD RIDGE ACROSS THE CENTRAL SUBTROPICAL  
ATLANTIC WATERS CONTINUES TO SUPPORT STRONG TO NEAR GALE-FORCE W  
TO NW WINDS OVER THE WATERS BETWEEN THE NW COAST OF AFRICA TO  
ABOUT 30W WHERE SEAS ARE VERU ROUGH IN THE RANGE OF 13 TO 20 FT.  
 
FOR THE FORECAST W OF 55W, FRESH TO STRONG WINDS AND ROUGH SEAS  
ON EITHER SIDE OF THE FRONT, AND MAINLY N OF 25N, WILL CONTINUE TO  
AFFECT THE OFFSHORE WATERS FROM WEST TO EAST THROUGH SUN AS THE  
FRONT MOVES EASTWARD AS A COLD FRONT. THIS SYSTEM IS FORECAST TO  
REACH FROM 31N63W TO HISPANIOLA BY SAT MORNING, AND FROM 31N57W TO  
PUERTO RICO BY SUN MORNING. LOOKING AHEAD, A NEW COLD FRONT IS  
FORECAST TO ENTER THE OFFSHORE WATERS OF NE FLORIDA MON NIGHT INTO  
TUE, FOLLOWED BY FRESH TO STRONG NE TO E WINDS AND ROUGH SEAS.  
THESE MARINE CONDITIONS ARE FORECAST TO AFFECT MOST OF THE WATERS  
N OF 27N THROUGH THE MIDDLE OF THE NEXT WEEK.  
 
 
RAMOS  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab TPC Page
Main Text Page