630  
AXPZ20 KNHC 172200 CCA  
TWDEP  
 
TROPICAL WEATHER DISCUSSION...CORRECTED  
NWS NATIONAL HURRICANE CENTER MIAMI FL  
1605 UTC THU SEP 17 2026  
 
CORRECTED SPECIAL FEATURES SECTION  
 
TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM  
03.4S TO 30N, EAST OF 120W INCLUDING THE GULF OF CALIFORNIA, AND  
FROM THE EQUATOR TO 30N, BETWEEN 120W AND 140W. THE FOLLOWING  
INFORMATION IS BASED ON SATELLITE IMAGERY, WEATHER OBSERVATIONS,  
RADAR, AND METEOROLOGICAL ANALYSIS.  
 
BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH  
1545 UTC.  
   
..SPECIAL FEATURES  
CORRECTED  
 
GULF OF TEHUANTEPEC GALE WARNING: THE PRESSURE GRADIENT BETWEEN HIGH  
PRESSURE OVER SOUTHERN MEXICO AND THE EASTERN NORTH PACIFIC  
MONSOON TROUGH WILL SUPPORT STRONG TO NEAR-GALE FORCE N TO NE GAP  
WINDS ACROSS THE GULF OF TEHUANTEPEC INTO FRI. WINDS EARLIER  
THIS MORNING WERE AT GALE-FORCE, BUT HAVE RECENTLY DIMINISHED TO  
JUST BELOW GALE-FORCE. WINDS MAY AGAIN REACH MINIMAL GALE FORCE  
BRIEFLY TONIGHT ALONG WITH SEAS OF 7 TO 9 FT. WINDS WILL CONTINUE  
TO PULSE IN THE GULF AT FRESH TO STRONG SPEEDS THROUGH SAT  
MORNING, WITH SEAS LOWERING TO A PEAK OF AROUND 6 FT. PLEASE READ  
THE LATEST HIGH SEAS FORECAST ISSUED BY THE NATIONAL HURRICANE  
CENTER AT WEBSITE: HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFEP2.SHTML  
FOR MORE DETAILS.  
   
..TROPICAL WAVES  
 
A TROPICAL WAVE HAS IS ITS AXIS ALONG 97W FROM 05N NORTHWARD  
TO EXTREME SOUTHERN MEXICO. IT IS MOVING WESTWARD AT AROUND 10  
TO 15 KT. NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION IS  
FROM 09N TO 13N BETWEEN 90W AND 98W. AN AREA OF LOW PRESSURE  
COULD FORM IN ASSOCIATION TO THIS WAVE WELL OFFSHORE OF  
SOUTHWESTERN MEXICO WITHIN THE NEXT FEW DAYS. ENVIRONMENTAL  
CONDITIONS APPEAR CONDUCIVE FOR SOME GRADUAL DEVELOPMENT, AND  
A TROPICAL DEPRESSION IS LIKELY TO FORM LATE THIS WEEKEND OR  
EARLY NEXT WEEK WHILE IT GRADUALLY MOVES NORTHWESTWARD TURNING  
NORTHWARD OFF THE COAST OF SOUTHWESTERN MEXICO.  
 
THE AXIS OF A TROPICAL WAVE IS NEAR 115W FROM 06N TO 18N, MOVING  
WESTWARD AT 10 TO 15 KT. NUMEROUS MODERATE TO STRONG CONVECTION  
IS SEEN FROM 07N TO 11N BETWEEN 111W-119W, AND FROM 12.5N TO  
16N BETWEEN 114W AND 17W. ENVIRONMENTAL CONDITIONS APPEAR  
CONDUCIVE FOR GRADUAL DEVELOPMENT OF THIS SYSTEM, AND A TROPICAL  
DEPRESSION IS LIKELY TO FORM THIS WEEKEND OR EARLY NEXT WEEK AS  
IT MOVES WESTWARD ACROSS THE WESTERN PART OF THE EAST PACIFIC.  
   
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH  
 
THE MONSOON TROUGH AXIS EXTENDS FROM ALONG THE COAST OF NORTHWEST  
COLOMBIA WEST-SOUTHWEST TO ACROSS CENTRAL COSTA RICA, THEN TO  
10N85W TO 07N102W TO 10N110W AND TO 13N121W. SCATTERED MODERATE  
TO ISOLATED STRONG CONVECTION IS FROM 02N TO 07N BETWEEN 79W-95W.  
SCATTERED MODERATE CONVECTION IS WITHIN 120 NM NORTH OF THE  
TROUGH BETWEEN 103W-107W, AND FROM 07N TO 12N BETWEEN 117W-121W.  
   
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO  
 
PLEASE SEE SPECIAL FEATURES SECTION ABOVE FOR DETAILS ON A GALE  
WARNING FOR THE GULF OF TEHUANTEPEC.  
 
AN OVERNIGHT SCATTEROMETER SATELLITE DATA PASS GENERALLY INDICATED  
MOSTLY GENTLE TO MODERATE NORTHWEST WINDS ACROSS THE CENTRAL AND  
SOUTHERN SECTIONS OF THE GULF OF CALIFORNIA. SEAS ARE 2 TO 4 FT  
IN THE GULF, EXCEPT FOR SLIGHTLY HIGHER SEAS OF 3 TO 5 FT AT  
THE ENTRANCE DUE TO LONG-PERIOD SOUTHWEST SWELL.  
 
FOR THE FORECAST, PLEASE SEE THE SPECIAL FEATURES SECTION FOR  
INFORMATION ABOUT THE GALE WARNING IN THE GULF OF TEHUANTEPEC.  
GENTLE TO MODERATE BREEZES AND MODERATE SEAS WILL PERSIST  
ELSEWHERE THROUGH THE END OF THE WEEK. MEANWHILE, A TROPICAL  
WAVE IS PRODUCING DISORGANIZED SHOWERS AND THUNDERSTORMS SOUTH OF  
ACAPULCO. LOOKING AHEAD, ENVIRONMENTAL CONDITIONS APPEAR  
CONDUCIVE FOR GRADUAL DEVELOPMENT, AND THERE IS A HIGH CHANCE A  
TROPICAL DEPRESSION MAY FORM LATE THIS WEEKEND OR EARLY NEXT  
WEEK WHILE IT MOVES NORTH-NORTHWESTWARD OR NORTHWARD AT 5 TO 10  
KT OFF SOUTHWEST MEXICO.  
 
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,  
AND WITHIN 750 NM OF ECUADOR...  
 
FRESH TO STRONG EASTERLY WINDS, AND MODERATE TO ROUGH SEAS,  
PREVAIL ACROSS THE GULF OF PAPAGAYO REGION, EXTENDING DOWNSTREAM  
TO NEAR 92W. MODERATE TO FRESH EAST WINDS EXTEND DOWNSTREAM FROM  
THE GULF OF PAPAGAYO TO THE OUTER OFFSHORE WATERS OF EL SALVADOR  
AND GUATEMALA.  
 
FOR THE FORECAST, THE PRESSURE GRADIENT BETWEEN A RIDGE NORTH  
OF THE AREA AND THE EASTERN NORTH PACIFIC MONSOON TROUGH WILL  
SUPPORT PULSING FRESH TO OCCASIONALLY STRONG EASTERLY WINDS AND  
MODERATE TO ROUGH SEAS ACROSS THE PAPAGAYO REGION TODAY, THEN  
PULSING TO MODERATE TO FRESH THEREAFTER. MODERATE WINDS AND SEAS  
WILL PREVAIL ELSEWHERE.  
   
..REMAINDER OF THE AREA  
 
THE 1005 MB REMNANT LOW OF TROPICAL DEPRESSION FIFTEEN-E IS  
LOCATED NEAR 15N132W. AN OVERNIGHT 0641Z SCATTEROMETER SATELLITE  
DATA PASS SHOWS FRESH TO STRONG NORTHEAST WINDS OVER THE WATERS  
TO THE NORTHWEST OF THE LOW PRESSURE NEAR 26N. SEAS ARE 7 TO 10  
FT WITH THESE WINDS PER OVERNIGHT SCATTEROMETER SATELLITE  
ALTIMETER DATA. SATELLITE IMAGERY SHOWS NUMEROUS STRONG  
CONVECTION FROM 14N TO 17N BETWEEN 129W AND 135W. SCATTERED  
MODERATE TO ISOLATED STRONG CONVECTION IS PRESENT FROM 06N  
TOM 09N BETWEEN 130W AND 135W, AND FROM 13N TO 18N BETWEEN  
123W AND 128W. SCATTERED MODERATE CONVECTION IS WITHIN  
30 NM OF A LINE FROM 06N TO 09N BETWEEN 130W AND 135W. FRESH TO  
STRONG WINDS, AND ROUGH SEAS, SUPPORTED BY THE PRESSURE GRADIENT  
BETWEEN THE AREA OF LOW PRESSURE AND THE SUBTROPICAL RIDGE NORTH  
OF THE AREA, COVER THE WATERS FROM 15N TO 25N WEST OF 125W. GENTLE  
TO MODERATE WINDS AND 4 TO 6 FT COMBINED SEAS IN MIXED SWELL ARE  
NOTED ELSEWHERE.  
 
FOR THE FORECAST, ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR  
GRADUAL DEVELOPMENT OF THE TROPICAL WAVE ALONG 115W, AND A  
TROPICAL DEPRESSION IS LIKELY TO FORM THIS WEEKEND OR EARLY NEXT  
WEEK AS IT MOVES WESTWARD ACROSS THE WESTERN PART OF THE EAST  
PACIFIC. FARTHER WEST, A BROAD AREA OF FRESH TO STRONG NORTHEAST  
TO EAST WINDS AND MODERATE TO ROUGH SEAS IN NORTH SWELL WILL  
PERSIST THROUGH THE REMAINDER OF THE WEEK FROM 15N TO 25N WEST OF  
125W. ALSO, AS DESCRIBED IN THE TROPICAL WAVE SECTION ABOVE,  
THERE IS SOME POTENTIAL FOR TROPICAL CYCLONE DEVELOPMENT  
ASSOCIATED WITH A TROPICAL WAVE NEAR 97W.  
 
 
AGUIRRE  
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