136
AXNT20 KNHC 170511
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0615 UTC THU SEP 17 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
0500 UTC.
..TROPICAL WAVES
THE AXIS OF AN EASTERN ATLANTIC TROPICAL WAVE IS NEAR 27W, SOUTH
OF 16N, MOVING WESTWARD AT 10-15 KT. SCATTERED MODERATE
CONVECTION IS NOTED FROM 05N TO 16N BETWEEN 25W AND 34W.
THE AXIS OF AN EASTERN CARIBBEAN TROPICAL WAVE IS NEAR 66W, SOUTH
OF 22N, MOVING WESTWARD AT 10 TO 15 KT. SCATTERED MODERATE
CONVECTION IS NOTED FROM 13N TO 23N BETWEEN 59W AND 67W.
..MONSOON TROUGH/ITCZ
THE MONSOON TROUGH ENTERS THE ATLANTIC NEAR 18N16W TO 09N37W. THE
ITCZ EXTENDS FROM 09N37W TO 08N57W. ASIDE FROM CONVECTION NOTED
IN THE TROPICAL WAVES SECTION ABOVE, SCATTERED MODERATE
CONVECTION IS NOTED WITHIN 90 NM N OF THE ITCZ BETWEEN 44W AND
55W.
..GULF OF AMERICA
FRESH TO STRONG WINDS, AND MODERATE SEAS, PREVAIL IN THE NE GULF
AS A PRESSURE GRADIENT RELATED TO HIGH PRESSURE OVER THE EASTERN
U.S. THAT STRETCHES A RIDGE SW TO THE SE US. ELSEWHERE, MODERATE
OR WEAKER WINDS, AND SLIGHT SEAS, ARE NOTED.
FOR THE FORECAST, FRESH TO STRONG NE TO E WINDS AND MODERATE TO
ROUGH SEAS WILL SPREAD WESTWARD OVER THE NORTHERN GULF WATERS
THROUGH LATE THU NIGHT BEFORE IMPROVING FRI INTO SAT, LEADING TO
MODERATE OR WEAKER WINDS AND SLIGHT TO MODERATE SEAS DURING THE
WEEKEND. MEANWHILE, A RATHER BROAD MID TO UPPER-LEVEL TROUGH WILL
MOVE TOWARDS FLORIDA FROM THE WESTERN ATLANTIC THU THROUGH FRI AS
IT TRANSITIONS INTO A LOW PRESSURE. THIS FEATURE WILL LEAD TO
INCREASING SHOWER AND THUNDERSTORM ACTIVITY OVER THE EASTERN AND
CENTRAL GULF WATERS.
..CARIBBEAN SEA
THE PRESSURE GRADIENT BETWEEN RIDGING NORTH OF THE AREA ALONG
WITH LOWER PRESSURE OVER COLOMBIA-VENEZUELA IS SUPPORTING FRESH TO
NEAR-GALE TRADES OVER THE S CENTRAL CARIBBEAN. MODERATE TO ROUGH
SEAS ARE OVER THESE WATERS. MODERATE TO FRESH WINDS, AND MODERATE
SEAS, ARE ELSEWHERE EAST OF 80W. W OF 80W, GENTLE TO MODERATE
WINDS, AND SLIGHT TO MODERATE SEAS, PREVAIL.
FOR THE FORECAST, FRESH TO NEAR GALE-FORCE TRADES ALONG WITH
MODERATE TO ROUGH SEAS WILL PREVAIL OVER MOST OF THE CENTRAL
CARIBBEAN THROUGH THE END OF THE WEEK. OTHERWISE, MODERATE TO
FRESH TRADES AND MODERATE SEAS WILL CONTINUE ACROSS THE EASTERN
CARIBBEAN THROUGH THE WEEKEND WHILE WINDS DIMINISH AND SEAS
SUBSIDE ELSEWHERE AS THE PRESSURES GRADIENT RELAXES. A TROPICAL
WAVE CURRENTLY IN THE EASTERN CARIBBEAN WILL REACH THE WESTERN
CARIBBEAN DURING THE UPCOMING WEEKEND. SCATTERED SHOWERS AND
THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF THE WAVE.
..ATLANTIC OCEAN
A STATIONARY FRONT EXTENDS FROM NEAR BERMUDA WEST-SOUTHWESTWARD TO
THE N BAHAMAS. FRESH TO STRONG WINDS, AND MODERATE TO ROUGH SEAS,
PREVAIL N OF THE FRONT. LIGHT TO GENTLE WINDS, AND SLIGHT SEAS,
ARE SE OF THE FRONT N OF 22N AND W OF 55W. FRESH TO STRONG WINDS,
AND MODERATE SEAS, ARE NOTED NEAR THE CANARY ISLANDS. ELSEWHERE,
GENTLE TO MODERATE WINDS AND MODERATE SEAS PREVAIL.
FOR THE FORECAST WEST OF 55W, FRESH NORTHEAST WINDS AND MODERATE
SEAS WILL PREVAIL W OF THE FRONT THROUGH THU. CONDITIONS WILL
IMPROVE LATE THU INTO FRI AS HIGH PRESSURE BECOMES THE DOMINANT
FEATURE ACROSS THE BASIN INTO THE WEEKEND. MEANWHILE, A BROAD MID
TO UPPER-LEVEL TROUGH LOCATED JUST EAST OF THE SOUTHEASTERN
BAHAMAS IN COMBINATION WITH A VERY MOIST AND UNSTABLE ENVIRONMENT
WILL CONTINUE TO SUPPORT SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS OVER MOST OF THE FORECAST WATERS THROUGH THE NEXT
FEW DAYS AS THE TROUGH GRADUALLY TRANSITIONS TO A LOW PRESSURE
THAT WILL BE MOVING IN A WEST TO NORTHWEST DIRECTION.
ERA
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