918
AXNT20 KNHC 210406
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0615 UTC SAT DEC 21 2024
TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA, CENTRAL AMERICA
GULF OF MEXICO, 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
0355 UTC.
.MONSOON TROUGH/ITCZ
THE MONSOON TROUGH ENTERS THE ATLANTIC THROUGH THE COAST OF
SOUTHERN LIBERIA NEAR 05N08W AND CONTINUES WESTWARD TO 04N18W.
THE ITCZ STRETCHES FROM 04N18W TO 04N35W AND TO NE BRAZIL NEAR
03N51W. SCATTERED MODERATE CONVECTION IS OBSERVED FROM 03N TO 07N
AND BETWEEN 32W AND 39W.
..GULF OF MEXICO
A WEAK COLD FRONT EXTENDS ACROSS THE FLORIDA STRAITS TO JUST OFF
NORTHERN YUCATAN AND GENERALLY DRY CONDITIONS ARE FOUND ACROSS THE
NORTHERN AND EASTERN GULF WATERS AND THE BAY OF CAMPECHE. HOWEVER,
A FEW SHOWERS ARE SEEN IN THE WESTERN GULF, ALSO AFFECTING
TAMAULIPAS. A STRONG RIDGE OVER THE NORTHERN US EXTENDS INTO THE
GULF OF MEXICO, FORCING FRESH TO LOCALLY STRONG NORTHERLY WINDS IN
THE NORTHERN GULF WATERS, ESPECIALLY NORTH OF 27N. SEAS IN THESE
WATERS ARE 4-6 FT. ELSEWHERE, MODERATE TO LOCALLY FRESH NORTHERLY
WINDS AND MODERATE SEAS ARE PREVALENT.
FOR THE FORECAST, A COLD FRONT WILL ENTER THE NORTHERN GULF OF MEXICO
TONIGHT AND DRIFT SOUTHWARD THIS WEEKEND BEFORE DISSIPATING OVER
THE EASTERN BASIN ON SUN. FRESH TO LOCALLY STRONG N TO NE WINDS
WILL OCCUR ALONG AND BEHIND THE FRONT TONIGHT INTO EARLY SAT NORTH
OF 28N. OTHERWISE, MODERATE TO LOCALLY FRESH N TO NE WINDS WILL
PREVAIL OVER THE REMAINDER OF THE GULF TONIGHT THROUGH SAT IN THE
WAKE OF ANOTHER COLD FRONT IN THE FAR SOUTHEASTERN BASIN. HIGH
PRESSURE WILL BUILD OVER THE CENTRAL UNITED STATES THIS WEEKEND
AND DRIFT SLOWLY EASTWARD, AND RIDGING WILL EXTEND INTO THE GULF
OF MEXICO, RESULTING INTO MODERATE NE TO E WINDS THIS WEEKEND INTO
NEXT WEEK.
..CARIBBEAN SEA
A DISSIPATING FRONT EXTENDS FROM CENTRAL CUBA TO NE YUCATAN, BUT
NO SIGNIFICANT CONVECTION IS NOTED WITH THIS BOUNDARY. FARTHER
EAST, A SURFACE TROUGH AND DIVERGENCE ALOFT SUPPORT SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS IN THE NORTH-CENTRAL CARIBBEAN,
AFFECTING PORTIONS OF HISPANIOLA, PUERTO RICO AND THE US VIRGIN
ISLANDS. LOCALIZED HEAVY RAINFALL MAY OCCUR, RESULTING IN FLASH
FLOODING. SCATTERED SHOWERS ARE ALSO NOTED IN THE SW CARIBBEAN
WATERS, IMPACTING SE NICARAGUA, COSTA RICA AND PANAMA. ELSEWHERE,
GENERALLY DRY CONDITIONS ARE PRESENT.
THE PRESSURE GRADIENT HAS RELAXED SOME IN THE CARIBBEAN SEA,
ALLOWING FOR MODERATE TO LOCALLY FRESH NE-E WINDS AND MODERATE
SEAS. HOWEVER, DUE TO THE PRESENCE OF THE SURFACE TROUGH, WEAKER
WINDS ARE NOTED IN THE NORTH-CENTRAL CARIBBEAN WATERS.
FOR THE FORECAST, MODERATE TO LOCALLY FRESH NE WINDS WILL OCCUR ACROSS
THE WESTERN HALF OF THE CARIBBEAN THROUGH SUN AS A SERIES OF
WEAKENING COLD FRONTS DRIFT SOUTHWARD AND DISSIPATE THIS WEEKEND.
ELSEWHERE, MODERATE TO LOCALLY FRESH TRADES WILL PREVAIL OVER THE
CENTRAL AND EASTERN CARIBBEAN. SLIGHT TO MODERATE SEAS WILL
DOMINATE THE BASIN THIS WEEKEND. LOOKING AHEAD, HIGH PRESSURE WILL
BUILD OVER THE EASTERN UNITED STATES AND WESTERN ATLANTIC EARLY
NEXT WEEK IN THE WAKE OF MULTIPLE COLD FRONTS MOVING OFF THE EAST
COAST. A STRENGTHENING PRESSURE GRADIENT BETWEEN THESE FEATURES
WILL LEAD TO FRESH TO LOCALLY STRONG NE TO E WINDS ACROSS MUCH OF
THE CARIBBEAN MON THROUGH WED, PARTICULARLY THROUGH THE WINDWARD
PASSAGE.
..ATLANTIC OCEAN
A COLD FRONT EXTENDS FROM A LOW PRESSURE SYSTEM OFF NEW ENGLAND TO
THE NW BAHAMAS AND THE FLORIDA STRAITS. ANOTHER FRONTAL BOUNDARY
IS ANALYZED AHEAD, EXTENDING FROM NEAR 31N71W TO THE CENTRAL
BAHAMAS AND CENTRAL CUBA. A RECENT SCATTEROMETER SATELLITE PASS
ALSO DEPICT A SURFACE TROUGH EXTENDING FROM 30N70W TO A 1013 MB
LOW PRESSURE JUST NORTH OF THE TURKS AND CAICOS ISLANDS AND
CONTINUING TO HAITI. DIVERGENCE ALOFT IS SUSTAINING SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS EAST OF THE SURFACE TOUGH TO
60W. FRESH TO STRONG W-NW WINDS AND SEAS OF 6-9 FT ARE OCCURRING
BEHIND THE FRONTAL BOUNDARIES AND NORTH OF THE BAHAMAS. MEANWHILE,
FRESH TO LOCALLY STRONG SE-S WINDS ARE NOTED BETWEEN 55W AND 68W.
SEAS IN THE AREA DESCRIBED ARE ALSO 6-9 FT AND CONFIRMED BY AN
ALTIMETER PASS FROM A FEW HOURS AGO. ELSEWHERE IN THE SW NORTH
ATLANTIC (WEST OF 55W), MODERATE OR WEAKER WINDS AND MODERATE SEAS
ARE PREVALENT.
FARTHER EAST, A 1009 MB LOW PRESSURE SYSTEM CENTERED NEAR 32N43W
EXTENDS A STATIONARY FRONT SOUTHWARD FROM A TRIPLE POINT AXIS NEAR
31N38W TO 18N49W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION
IS FOUND AHEAD OF THE FRONTAL BOUNDARY TO 30W AND NORTH OF 23W.
THE PRESSURE GRADIENT BETWEEN A 1042 MB RIDGE JUST NORTH OF THE
AZORES AND THE AFOREMENTIONED LOW, FRONT AND LOWER PRESSURES IN
THE DEEP TROPICS RESULT IN FRESH TO NEAR GALE-FORCE NE-E WINDS
EAST OF THE FRONT AND NORTH OF 18N. SEAS IN THESE WATERS ARE
MODERATE TO ROUGH, PEAKING NEAR 10 FT OFF MOROCCO AND 31N37W.
MARINERS ARE ADVISED THAT GALE-FORCE WINDS ARE LIKELY OCCURRING IN
ASSOCIATION WITH THE STRONGEST CONVECTION BASED ON SATELLITE-DERIVED
WIND DATA. MODERATE OR WEAKER WINDS AND MODERATE SEAS ARE
PREVALENT ELSEWHERE.
FOR THE FORECAST W OF 55W, A SERIES OF COLD FRONTS MOVING OFF THE
SOUTHEASTERN COAST OF THE UNITED STATES WILL PROGRESS SLOWLY
EASTWARD THIS WEEKEND INTO EARLY NEXT WEEK. FRESH TO STRONG NW
WINDS WILL OCCUR BEHIND THESE FRONTS NORTH OF 27.5N THROUGH SAT
MORNING, WITH THE STRONGEST WINDS OCCURRING NORTH OF 29.5N AND
WEST OF 72W. ROUGH SEAS ASSOCIATED WITH THESE FRONTS WILL SPREAD
SOUTH AND EAST, WITH SEAS IN EXCESS OF 8 FT OCCURRING NORTH OF
27N. FARTHER EAST, RIDGING WILL DRIFT EASTWARD, AND FRESH S TO SE
WINDS WILL OCCUR THROUGH SAT MORNING ALONG THE PERIPHERY OF THE
RIDGE, GENERALLY NORTH OF 20N AND EAST OF 65W. SOUTH OF 20N,
MODERATE TO AT TIMES FRESH TRADES WILL PREVAIL INTO THE MIDDLE OF
NEXT WEEK. LOOKING AHEAD, WIDESPREAD FRESH TO LOCALLY STRONG NE
WINDS AND ROUGH SEAS WILL REDEVELOP NORTH OF 20N SUN NIGHT THROUGH
EARLY NEXT WEEK AS STRONG HIGH PRESSURE BUILDS ACROSS THE WESTERN
ATLANTIC AND INTO THE LOCAL REGION, BEHIND A WEAKENING COLD
FRONT.
DELGADO
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