400  
AXNT20 KNHC 171053  
TWDAT  
 
TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL  
1215 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH  
1030 UTC.  
   
..TROPICAL WAVES  
 
A TROPICAL WAVE AXIS IS NEAR 30W, FROM 03N TO 17N, MOVING WESTWARD  
AT 10-15 KT. SCATTERED MODERATE CONVECTION IS NOTED FROM 05N TO  
16N BETWEEN 26W AND 38W.  
 
A TROPICAL IS IN THE E CARIBBEAN WITH AXIS NEAR 67W, SOUTH OF  
22N, MOVING WESTWARD AT 10 TO 15 KT. SCATTERED MODERATE CONVECTION  
IS NOTED FROM 14N TO 24N BETWEEN 56W AND 70W.  
   
..MONSOON TROUGH/ITCZ  
 
THE MONSOON TROUGH ENTERS THE ATLANTIC NEAR 17N16W TO 09N37W. THE  
ITCZ EXTENDS FROM 09N37W TO 09N56W. ASIDE FROM CONVECTION NOTED  
IN THE TROPICAL WAVES SECTION ABOVE, SCATTERED MODERATE CONVECTION  
IS NOTED FROM 05N TO 11N BETWEEN 10W AND 21W, AND FROM 06N TO 11N  
BETWEEN 44W AND 54W.  
   
..GULF OF AMERICA  
 
THE GRADIENT RELATED TO HIGH PRESSURE OVER THE SE U.S. THAT  
STRETCHES A RIDGE SW TO THE GULF IS SUSTAINING FRESH NE TO E WINDS  
AND MODERATE SEAS OVER THE NE AND NORTH-CENTRAL GULF. ELSEWHERE,  
MODERATE OR WEAKER WINDS, AND SLIGHT SEAS, ARE NOTED.  
 
FOR THE FORECAST, FRESH WINDS AND MODERATE SEAS WILL SPREAD  
WESTWARD TO THE NW GULF WATERS TODAY BEFORE IMPROVING FRI INTO  
SAT. A BROAD UPPER-LEVEL LOW WILL MOVE TOWARDS FLORIDA FROM THE  
WESTERN ATLANTIC TODAY THROUGH FRI. 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, THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE  
OVER THE WESTERN ATLANTIC AND RELATIVELY LOWER PRESSURE IN NW  
COLOMBIA WILL GENERALLY MAINTAIN FRESH TO LOCALLY NEAR GALE-FORCE  
TRADES ALONG WITH MODERATE TO LOCALLY ROUGH SEAS 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 MOVING ACROSS THE MONA PASSAGE WILL REACH  
THE WESTERN CARIBBEAN OVER THE 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 NE WINDS AND MODERATE 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 NE WINDS, AND MODERATE SEAS, ARE  
NOTED NEAR THE CANARY ISLANDS, EXTENDING SW TO NEAR 38W.  
ELSEWHERE, GENTLE TO MODERATE WINDS AND MODERATE SEAS PREVAIL.  
 
FOR THE FORECAST WEST OF 55W, A TIGHT PRESSURE GRADIENT BETWEEN  
HIGH PRESSURE OVER THE SOUTHEASTERN U.S. AND THE STATIONARY FRONT  
WILL MAINTAIN MOSTLY FRESH NORTHEAST WINDS AND MODERATE SEAS W OF  
THE FRONT THROUGH TODAY. CONDITIONS WILL IMPROVE LATE TODAY INTO  
FRI AS HIGH PRESSURE BECOMES THE DOMINANT FEATURE ACROSS THE BASIN  
INTO THE WEEKEND. A BROAD UPPER-LEVEL LOW LOCATED JUST EAST OF  
THE NORTHERN 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 THE  
NEXT FEW DAYS AS IT MOVES IN A WEST TO NORTHWEST DIRECTION.  
 
 
RAMOS  
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