542
AXNT20 KNHC 131720
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1815 UTC SAT DEC 13 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
1700 UTC.
..SPECIAL FEATURES
WEST ATLANTIC GALE WARNING: GALE FORCE WINDS ARE FORECAST TO
BEGIN AT 15/0000 UTC, LASTING THROUGH 15/1200 UTC, NORTHWEST OF A
COLD FRONT THAT WILL MOVE ACROSS THE WESTERN ATLANTIC WATERS.
SEAS WILL RANGE FROM 12-14 FT. 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 GALE WARNING: METEOFRANCE HAS ISSUED A GALE
WARNING FOR THE MADEIRA AND CANARIAS MARINE ZONES. FOR MADEIRA,
THE WARNING IS VALID THROUGH 13/2100 UTC, AND FOR CANARIAS, THE
WARNING IS VALID THROUGH 14/0000 UTC. PLEASE READ THE LATEST HIGH SEAS
FORECAST ISSUED BY METEOFRANCE AT:
HTTPS://WWMIWS.WMO.INT/INDEX.PHP/METAREAS/AFFICHE/2 FOR MORE
INFORMATION.
EAST ATLANTIC SIGNIFICANT SWELL EVENT: CONTINUING STRONG TO NEAR-
GALE FORCE NORTH WINDS IN THE LEE OF A DISSIPATED FRONTAL BOUNDARY
HAS BUILT A SIGNIFICANT AREA OF LARGE, LONG PERIOD N SWELL IN THE
EASTERN ATLANTIC OCEAN. SEAS 12 FT OR GREATER ARE NORTH OF 15N AND
EAST OF 35W, WITH PEAK SEAS TO 22 FT NEAR THE CANARY ISLANDS. THE
SWELL DIRECTION IS N WITH 15-19 SEC PERIODS. PEAK SEAS ARE
FORECAST TO DIMINISH TONIGHT, SUBSIDING BELOW 12 FT BY EARLY
MONDAY MORNING. PLEASE READ THE LATEST HIGH SEAS FORECAST ISSUED
BY METEOFRANCE AT: HTTPS://WWMIWS.WMO.INT/INDEX.PHP/METAREAS/AFFICHE/2
FOR MORE INFORMATION.
..MONSOON TROUGH/ITCZ
THE MONSOON TROUGH ENTERS THE ATLANTIC THROUGH 08N13W AND EXTENDS
TO 05N19W. THE ITCZ CONTINUES FROM 05N19W TO 01N50W. SCATTERED
MODERATE CONVECTION IS FROM 03N TO 11N EAST OF 28W.
GULF OF AMERICA...
SCATTERED MODERATE CONVECTION, ASSOCIATED WITH A SURFACE TROUGH,
IS FROM 25N TO 29N BETWEEN 94W AND 96W IN THE NW GULF WATERS.
1024 MB HIGH PRESSURE CENTERED OVER N FLORIDA PROVIDES FOR GENTLE
TO MODERATE E TO SE WINDS ACROSS THE GULF, WITH 2-4 FT SEAS.
LOCALLY FRESH WINDS ARE EVIDENT ON A RECENT SATELLITE
SCATTEROMETER PASS IN THE STRAITS OF FLORIDA. A FEW SHOWERS AND
TSTORMS ARE ALSO EVIDENT IN THE STRAITS ON SATELLITE IMAGERY.
FOR THE FORECAST, WEAK HIGH PRESSURE LOCATED OVER NORTH FLORIDA
AND THE ADJACENT ATLANTIC WILL SLIDE NORTHEASTWARD AND INTO THE NW
ATLANTIC THROUGH TONIGHT TO PRODUCE MODERATE TO OCCASIONALLY
FRESH E TO SE WINDS ACROSS THE S AND W GULF. OTHERWISE, MODERATE
OR WEAKER WINDS AND SLIGHT SEAS ARE EXPECTED OVER THE REMAINDER OF
THE BASIN THROUGH SAT. THE NEXT COLD FRONT IS EXPECTED TO ENTER
THE NORTHERN GULF ON SUN MORNING, BRINGING STRONG N TO NE WINDS
AND BUILDING SEAS BEHIND THE FRONT. THE FRONT IS EXPECTED TO REACH
THE SOUTH-CENTRAL GULF ALONG 24N BY MON MORNING, AND MOVE SOUTH
OF THE BASIN MON NIGHT.
CARIBBEAN SEA...
RECENT SATELLITE SCATTEROMETER DATA INDICATES PULSING STRONG TO
NEAR-GALE FORCE WINDS IN THE SOUTH-CENTRAL CARIBBEAN OFF THE COAST
OF COLOMBIA. SEAS ARE 7-9 FT IN THIS REGION. ELSEWHERE, IN THE
CENTRAL CARIBBEAN, FRESH TO STRONG WINDS AND 5-7 FT SEAS PREVAIL.
FRESH NE WINDS ARE ALSO NOTED IN THE WINDWARD PASSAGE. THESE
WINDS ARE THE RESULTS OF STRONG HIGH PRESSURE OVER THE SUBTROPICAL
ATLANTIC AND LOWER PRESSURE OVER SOUTH AMERICA. A SURFACE TROUGH,
THE REMNANTS OF THE LAST FRONTAL BOUNDARY, PERSISTS IN THE NW
CARIBBEAN WATERS. SCATTERED SHOWERS AND TSTORMS ARE IN THESE
WATERS. NE WINDS ARE GENTLE TO MODERATE, WITH 3-5 FT SEAS. IN THE
E CARIBBEAN, MODERATE TO FRESH TRADES AND 5-7 FT SEAS PREVAIL.
FOR THE FORECAST, FRESH TO STRONG WINDS AND MODERATE TO ROUGH
SEAS ARE EXPECTED OVER THE CENTRAL CARIBBEAN THROUGH SUN MORNING
DUE TO THE PRESSURE GRADIENT BETWEEN THE COLOMBIAN LOW AND A
MODEST WESTERN ATLANTIC RIDGE. WINDS WILL PULSE TO NEAR GALE-FORCE
AT NIGHT OFFSHORE OF NORTHERN COLOMBIA. ELSEWHERE, FRESH TO
LOCALLY STRONG TRADE WINDS AND ROUGH SEAS IN LARGE E SWELL WILL
PREVAIL OVER THE 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 MON, ACCOMPANIED BY
INCREASING WINDS AND BUILDING SEAS BEHIND THE FRONT. THIS FRONT IS
EXPECTED TO REACH FROM CENTRAL CUBA TO N BELIZE TUE EVENING, THEN
WILL BEGIN TO STALL AND WEAKEN THROUGH WED.
ATLANTIC OCEAN...
PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION ON
GALE WARNINGS FOR THE WESTERN AND EASTERN ATLANTIC OCEAN, AND A
SIGNIFICANT SWELL EVENT IN THE EASTERN ATLANTIC.
STRONG 1032 MB HIGH PRESSURE CENTERED NEAR 32N32W CONTINUES TO
BUILD ACROSS THE EASTERN AND CENTRAL TROPICAL ATLANTIC, AND
SUPPORT N WINDS TO GALE FORCE NEAR THE CANARY ISLANDS, WHERE A
GALE WARNING REMAINS IN EFFECT. STRONG TO NEAR-GALE FORCE N WINDS
BECOME FRESH TO STRONG NE WINDS SOUTH OF 25N TO THE ITCZ. THESE
WEATHER CONDITIONS HAVE BUILT A LARGE AREA OF SWELL WITH SEAS IN
EXCESS OF 8 FT OVER THE ENTIRE ATLANTIC OCEAN EAST OF 60W. WEST OF
40W, THE SWELL DIRECTION IS PRIMARILY E WITH 12-13 SEC PERIODS.
EAST OF 40W, THE SWELL DIRECTION IS N WITH 15-19 SEC PERIODS.
DESCRIPTIONS OF AREAS WITH HIGHER SEAS ASSOCIATED WITH THE
SIGNIFICANT SWELL EVENT ARE FOUND IN SPECIAL FEATURES. ELSEWHERE,
4-7 FT SEAS AND MODERATE OR WEAKER WINDS PREVAIL.
FOR THE FORECAST, THE STATIONARY FRONT IS FORECAST TO LIFT
NORTHWARD AND DISSIPATE. THE NEXT STRONG COLD FRONT IS SLATED TO
MOVE OFF THE COAST OF THE SOUTHEASTERN UNITED STATES ON SUN, WITH
STRONG TO GALE-FORCE WINDS AND QUICKLY BUILDING SEAS EXPECTED
BEHIND THE FRONT THROUGH MON MORNING. THE FRONT IS FORECAST TO
REACH FROM JUST E OF BERMUDA TO THE CENTRAL BAHAMAS BY MON
MORNING, THEN WEAKEN CONSIDERABLY AS IT REACHES FROM 30N55W TO THE
SE BAHAMAS AND CENTRAL CUBA TUE MORNING. LARGE N SWELL WILL BUILD
IN ACROSS THE REGIONAL WATERS BEHIND THE FRONT SUN NIGHT THROUGH
TUE MORNING BEFORE SUBSIDING.
MAHONEY
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