818  
AXNT20 KNHC 171015  
TWDAT  
 
TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL  
1215 UTC THU JUL 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH  
1000 UTC.  
   
..TROPICAL WAVES  
 
A FAR EASTERN ATLANTIC TROPICAL WAVE IS ALONG 27W, FROM 09N TO  
22N, MOVING WESTWARD AT 10-15 KT. WIDELY SCATTERED SHOWERS ARE  
SEEN FROM 07.5N TO 12N BETWEEN 22W AND 28W.  
 
AN EASTERN CARIBBEAN TROPICAL WAVE IS ALONG 66W-67W, SOUTH OF  
20N, MOVING WESTWARD AT 20 KT. SCATTERED MODERATE CONVECTION IS  
NORTH OF PUERTO RICO AND HISPANIOLA TO 21.5N BETWEEN 64.5W AND  
72W, AND ALSO BEHIND THE WAVE FROM 12N TO 16N BETWEEN 63W AND 67W.  
 
A WESTERN CARIBBEAN TROPICAL WAVE IS ALONG 79W-80W, SOUTH OF 20N,  
MOVING WESTWARD AT 20 KT. SCATTERED MODERATE TO STRONG CONVECTION  
IS OCCURRING ACROSS SOUTHERN PORTIONS OF THE WAVE NEAR THE MONSOON  
TROUGH ACROSS WESTERN PANAMAS AND IN THE EASTERN PACIFIC ALONG AND  
OFFSHORE OF COLOMBIA.  
   
..MONSOON TROUGH/ITCZ  
 
 
THE MONSOON TROUGH ENTERS THE ATLANTIC NEAR THE BORDER OF SENEGAL  
AND GUINEA-BISSAU ALONG 16.5W AND CONTINUES WEST SOUTHWESTWARD TO  
09N41W. THE ITCZ EXTENDS FROM 09N41W TO THE COAST OF FRENCH GUIANA  
NEAR 05.5N53W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS  
OBSERVED WITHIN 120 NM OF THE COAST OF AFRICA FROM 06N TO 11N, AND  
FROM 01.5N TO 11N BETWEEN 30W AND 58W.  
   
..GULF OF AMERICA  
 
OVERNIGHT SATELLITE SCATTEROMETER DATA INDICATED THAT THE  
DISTURBANCE (AL93) THAT THE NATIONAL HURRICANE CENTER HAS BEEN  
TRACKING OVER THE NORTHEAST AND NORTH-CENTRAL GULF WATERS REMAINS  
QUITE DISORGANIZED, WITH AN ELONGATED TROUGH EXTENDING NORTH TO  
SOUTH, CURRENTLY FROM MOBILE BAY TO 28N89W. PEAK WINDS DETECTED  
WERE 25 KT OR LESS. IN ADDITION, THE ASSOCIATED SHOWER AND  
THUNDERSTORM ACTIVITY REMAINS DISPLACED WELL WEST OF THE TROUGH,  
WITH SCATTERED TO LOCALLY NUMEROUS MODERATE TO STRONG CONVECTION  
NOTED NORTH OF 27.5N BETWEEN COASTAL MISSISSIPPI AND THE  
LOUISIANA-TEXAS BORDER. WHILE SOME ADDITIONAL DEVELOPMENT OF THIS  
SYSTEM REMAINS POSSIBLE OVER THE NEXT 12-24 HOURS, ITS CURRENT  
STRUCTURE SUGGESTS ITS CHANCES OF DEVELOPING INTO A TROPICAL  
DEPRESSION BEFORE IT REACHES THE LOUISIANA COAST LATER TODAY ARE  
DECREASING. THE DISTURBANCE HAS A LOW CHANCE OF TROPICAL  
DEVELOPMENT OVER THE NEXT 48 HOURS AND ALSO IN THE NEXT 7 DAYS.  
 
WEAK HIGH PRESSURE PERSISTS OVER THE NW GULF, AND IS SUPPORTING A  
WEAK PRESSURE GRADIENT ACROSS THE BASIN. THIS PATTERN IS  
SUPPORTING MODERATE TO LOCALLY FRESH SOUTHERLY WINDS IN THE NE  
AND NW GULF WATERS. SEAS IN THESE WATERS ARE 3-4 FT. MODERATE TO  
LOCALLY FRESH EASTERLY WINDS AND SLIGHT TO MODERATE SEAS ARE FOUND  
IN THE BAY OF CAMPECHE. ELSEWHERE, MODERATE OR WEAKER WINDS AND  
SLIGHT SEAS PREVAIL. SCATTERED MODERATE CONVECTION COVERS MUCH OF  
THE SOUTHEAST GULF THIS MORNING, SUPPORTED BY BROAD MIDDLE TO  
UPPER LEVEL LOW PRESSURE ACROSS THE NORTHERN BAHAMAS AND SOUTH  
FLORIDA.  
 
FOR THE FORECAST, AL93 IS FORECAST TO CONTINUE MOVING WESTWARD  
ACROSS NORTHERN PORTIONS OF THE GULF TODAY, REACHING SE LOUISIANA  
LATE TODAY. IF THIS SYSTEM MOVES FAR ENOUGH OFFSHORE, ENVIRONMENTAL  
CONDITIONS OVER THE GULF APPEAR GENERALLY FAVORABLE FOR  
ADDITIONAL DEVELOPMENT, AND A TROPICAL DEPRESSION COULD FORM OVER  
THE NEXT DAY OR TWO BEFORE THE SYSTEM MOVES FULLY INLAND BY FRI.  
REGARDLESS OF DEVELOPMENT, HEAVY SHOWERS AND THUNDERSTORMS ARE  
EXPECTED OVER THE NORTH- CENTRAL GULF THROUGH FRI, WITH ERRATIC  
GUSTY WINDS AND ROUGH SEAS POSSIBLE NEAR CONVECTION. ATLANTIC HIGH  
PRESSURE WILL SHIFT WESTWARD INTO THE NE GULF OVER THE WEEKEND.  
   
..CARIBBEAN SEA  
 
PLEASE SEE THE TROPICAL WAVE SECTION FOR MORE INFORMATION OF THE  
TROPICAL WAVES MOVING ACROSS THE BASIN.  
 
SCATTERED SHOWERS AND A FEW MILD THUNDERSTORMS DOT THE WATERS  
NORTH OF 17.5N SOUTH OF HISPANIOLA TO EASTERN JAMAICA AND THE  
WINDWARD PASSAGE, AS WELL AS NORTH OF 20N ACROSS THE WATERS OF  
WESTERN CUBA. DRIER CONDITIONS ARE PREVALENT ELSEWHERE, EXCEPT FOR  
SCATTERED SHOWERS ACROSS THE SOUTHEAST CARIBBEAN TRAILING THE  
TROPICAL WAVE THERE. THE TIGHT PRESSURE GRADIENT BETWEEN THE  
SUBTROPICAL RIDGE EXTENDING FROM NEAR BERMUDA TO NORTHERN FLORIDA  
AND GEORGIA, AND LOWER PRESSURES IN NW COLOMBIA RESULT IN STRONG  
TO NEAR GALE-FORCE EASTERLY WINDS IN THE SOUTH- CENTRAL  
CARIBBEAN. THIS WAS CONFIRMED BY OVERNIGHT SATELLITE SCATTEROMETER  
DATA. THESE WINDS ARE SUPPORTING ROUGH SEAS TO NEAR 11 FT OFF THE  
COAST OF COLOMBIA. FRESH TO LOCALLY STRONG EASTERLY BREEZES AND  
MODERATE SEAS ARE OCCURRING IN THE NORTH-CENTRAL CARIBBEAN,  
INCLUDING THE WINDWARD PASSAGE. MODERATE TO LOCALLY FRESH EASTERLY  
WINDS AND MODERATE SEAS ARE FOUND IN THE EASTERN CARIBBEAN AND  
GULF OF HONDURAS. IN THE REMAINDER OF THE BASIN, MODERATE OR  
WEAKER WINDS AND SLIGHT TO MODERATE SEAS PREVAIL.  
 
FOR THE FORECAST, FRESH TO STRONG TRADE WINDS AND ROUGH SEAS  
ACROSS THE SOUTH-CENTRAL CARIBBEAN WILL EXPAND ACROSS MOST OF THE  
CENTRAL AND INTO THE WEST-CENTRAL BASIN, INCLUDING THROUGH THE  
WINDWARD PASSAGE, TODAY THROUGH SAT MORNING, AS CENTRAL ATLANTIC  
HIGH PRESSURE ALONG 31N-32N GRADUALLY SHIFTS WESTWARD TO NEAR 75W.  
STRONG TO NEAR GALE-FORCE WINDS ARE EXPECTED OFFSHORE OF NORTHERN  
COLOMBIA AND IN THE GULF OF VENEZUELA EACH NIGHT AND EARLY  
MORNING INTO SAT. SCATTERED SHOWERS WILL MOVE WESTWARD THROUGH THE  
COASTAL WATERS OF THE GREATER ANTILLES THROUGH FRI, ASSOCIATED  
WITH THE PASSING TROPICAL WAVES. WINDS AND SEAS WILL DIMINISH  
SLIGHTLY SAT INTO EARLY NEXT WEEK AS HIGH PRESSURE WEAKENS NORTH  
OF THE AREA. ELSEWHERE, PULSING MODERATE TO FRESH E TO NE WINDS  
ARE EXPECTED IN THE GULF OF HONDURAS EACH AFTERNOON AND EVENING  
INTO THIS WEEKEND. MODERATE TO FRESH TRADE WINDS AND MODERATE SEAS  
WILL CONTINUE IN THE EASTERN BASIN INTO NEXT WEEK.  
   
..ATLANTIC OCEAN  
 
PLEASE SEE THE TROPICAL WAVE SECTION FOR MORE INFORMATION OF THE  
TROPICAL WAVES MOVING ACROSS THE BASIN.  
 
AN UPPER LEVEL LOW CENTERED OFF THE NW BAHAMAS IS INTERACTING WITH  
LOW LEVEL MOISTURE SHEARING NW AND AWAY FROM THE WESTERN CARIBBEAN  
TROPICAL WAVE, RESULTING IN SCATTERED SHOWERS AND ISOLATED  
THUNDERSTORMS AFFECTING THE NW BAHAMAS AND ADJACENT ATLANTIC  
WATERS AND INTO THE SOUTHEAST FLORIDA COASTAL WATERS. SIMILAR  
SHOWER AND THUNDERSTORM ACTIVITY IS ACROSS THE ATLANTIC WATERS OF  
HISPANIOLA AND PUERTO RICO, OCCURRING ACROSS NORTHERN PORTIONS OF  
THE EASTERN CARIBBEAN TROPICAL WAVE. FARTHER NORTHEAST, ANOTHER  
UPPER LEVEL LOW SITUATED EAST OF BERMUDA SUPPORTS A SCATTERED  
SHOWERS NORTH OF 28N AND BETWEEN 53W AND 64W. THE REMAINDER OF  
THE SW NORTH ATLANTIC, WEST OF 55W, IS DOMINATED BY A SUBTROPICAL  
RIDGE EXTENDING FROM A 1024 MB HIGH JUST EAST OF BERMUDA.  
SATELLITE SCATTEROMETER DATA DEPICTS FRESH TO LOCALLY STRONG  
EASTERLY WINDS BETWEEN THE SE BAHAMAS AND THE OFFSHORE WATERS  
NORTH OF PUERTO RICO, INCLUDING THE ENTRANCE OF THE WINDWARD  
PASSAGE. SEAS IN THESE WATERS ARE 5-8 FT. MODERATE TO FRESH  
EASTERLY WINDS AND MODERATE SEAS ARE FOUND SOUTH OF 25N AND WEST  
OF 50W.  
 
IN THE NORTH-CENTRAL ATLANTIC, A DISSIPATING COLD FRONT EXTENDS  
FROM 31N31W TO 21N54W. A FEW SHOWERS ARE ALONG THE BOUNDARY.  
MODERATE TO LOCALLY FRESH NE-E WINDS AND MODERATE SEAS ARE  
OCCURRING NORTH OF THIS DISSIPATING BOUNDARY. IN THE FAR NE  
ATLANTIC, FRESH TO STRONG N WINDS AND SEAS OF 5-8 FT ARE PRESENT  
NORTH OF 29N AND EAST OF 15W. IN THE REST OF THE BASIN, MODERATE  
OR WEAKER WINDS AND MODERATE SEAS ARE PREVALENT.  
 
FOR THE FORECAST WEST OF 55W, MODERATE TO LOCALLY FRESH E TO SE  
WINDS ARE EXPECTED NORTH OF THE GREATER ANTILLES TO 26N AND OFF  
THE COAST OF FLORIDA WEST OF 76W TODAY AS HIGH PRESSURE IN THE  
CENTRAL ATLANTIC ALONG 31N-32N BUILDS WESTWARD INTO FLORIDA, IN  
THE WAKE OF WESTWARD MOVING LOW PRESSURE OVER THE NE GULF OF  
AMERICA. SCATTERED SQUALLS AND THUNDERSTORMS WILL MOVE THROUGH THE  
NORTHERN BAHAMAS AND SOUTHEAST FLORIDA COASTAL WATERS THIS MORNING  
AND INTO THE CENTRAL FLORIDA NEAR AND OFFSHORE WATERS THIS  
AFTERNOON AND EVENING, ASSOCIATED WITH A TROPICAL WAVE PASSING  
SOUTH OF THE AREA. FRESH WINDS WILL PULSE TO STRONG EACH EVENING  
AND NIGHT OFF THE COAST OF NORTHERN HISPANIOLA INTO EARLY SAT.  
WINDS WILL DIMINISH OFF THE COAST OF FLORIDA BY EARLY FRI, AND  
NORTH OF THE GREATER ANTILLES AND THE BAHAMAS BY SAT MORNING AS  
HIGH PRESSURE SHIFTS TO NEAR 29N75W AND WEAKENS. SOUTH OF 20N,  
MODERATE TO OCCASIONALLY FRESH TRADE WINDS AND MODERATE SEAS WILL  
PREVAIL THROUGH THIS WEEKEND.  
 
 
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