613  
AXPZ20 KNHC 180131  
TWDEP  
 
TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL  
0405 UTC TUE AUG 18 2026  
 
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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH  
0100 UTC.  
   
..SPECIAL FEATURES  
 
GULF OF TEHUANTEPEC GALE WARNING: A VERY TIGHT LOCAL PRESSURE  
GRADIENT IS PRESENT OVER THE GULF OF TEHUANTEPEC AREA IN THE  
WAKE OF A DEPARTING TROPICAL WAVE WITH A TIGHT RIDGE OF HIGH  
PRESSURE NOSING DOWN EASTERN TO SOUTHEASTERN MEXICO, AS WELL AS A  
SURFACE TROUGH TO THE NORTHEAST OVER THE WESTERN YUCATAN  
PENINSULA. THIS PRESSURE IS LIKELY SUPPORTING MINIMAL GALE-FORCE  
NORTHERLY GAP WINDS IN THE GULF OF TEHUANTEPEC, WITH SEAS IN THE  
PROCESS OF BUILDING TO 8 TO 10 FT. WINDS ARE FORECAST TO DIMINISH  
BELOW GALE-FORCE TO FRESH TO STRONG BY EARLY TUE. PLEASE, REFER  
TO THE LATEST NWS HIGH SEAS FORECAST AVAILABLE AT WEBSITE:  
HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFEP2.SHTML FOR MORE DETAILS.  
   
..TROPICAL WAVES  
 
THE AXIS OF A TROPICAL WAVE IS NEAR 78W FROM 03N NEAR THE BORDER  
OF ECUADOR AND COLOMBIA NORTHWARD TO ACROSS EASTERN PANAMA NEAR  
THE BORDER WITH COLOMBIA, AND CONTINUING INTO THE CARIBBEAN SEA  
TO NEAR WESTERN JAMAICA, MOVING WESTWARD AT AROUND 10 KT.  
SCATTERED TO NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION IS  
NOTED FROM 02N TO 12N BETWEEN 77W AND 93W.  
 
THE AXIS OF A TROPICAL WAVE IS NEAR 98W FROM JUST WESTERN  
OFFSHORE OAXACA SOUTHWARD TO NEAR THE EQUATOR, MOVING SLOWLY  
WESTWARD AT AROUND 5 KT. SCATTERED MODERATE ISOLATED STRONG  
CONVECTION IS NOTED FROM 06N TO 13N BETWEEN 96W AND 103W. AN AREA  
OF LOW PRESSURE IS FORECAST TO FORM SEVERAL HUNDRED NAUTICAL  
MILES SOUTH OF THE COAST OF SOUTHERN MEXICO AROUND THE END OF THE  
WEEK. GRADUAL DEVELOPMENT OF THIS SYSTEM IS LIKELY THEREAFTER,  
AND A TROPICAL DEPRESSION IS EXPECTED TO FORM THIS WEEKEND WHILE  
THE SYSTEM MOVES WEST- NORTHWESTWARD, REMAINING WELL OFFSHORE OF  
MEXICO.  
 
THE AXIS OF A TROPICAL WAVE IS NEAR 126W FROM 01N TO 17N, MOVING  
WESTWARD AT AROUND 10 KT. SCATTERED MODERATE ISOLATED STRONG  
CONVECTION IS NOTED FROM 06N TO 14N BETWEEN 114W AND 136W. A  
BROAD AREA OF LOW PRESSURE IS EXPECTED TO FORM WELL TO THE EAST-  
SOUTHEAST OF THE HAWAIIAN ISLANDS DURING THE LATTER PART OF THIS  
WEEK. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR GRADUAL  
DEVELOPMENT OF THIS SYSTEM, AND A TROPICAL DEPRESSION COULD FORM  
TOWARDS THE END OF THE WEEK OR OVER THE WEEKEND WHILE THE SYSTEM  
MOVES GENERALLY WESTWARD ACROSS THE WESTERN PORTION OF THE EAST  
PACIFIC AND INTO THE CENTRAL PACIFIC.  
   
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH  
 
THE MONSOON TROUGH EXTENDS FROM 1009 MB LOW PRESSURE NEAR THE  
BORDER OF NW VENEZUELA AND NORTHERN COLOMBIA AT 09N72W TO ALONG  
NORTHERN PANAMA TO ACROSS COSTA RICA AND INTO THE PACIFIC NEAR  
09N84W TO 06.5N108W. THE ITCZ EXTENDS FROM 06.5N108W TO  
08.5N122W, THEN RESUMES WEST OF A TROPICAL WAVE FROM 09N129W TO  
BEYOND 08N140W. OTHER THAN THE CONVECTION DESCRIBED ABOVE WITH  
THREE TROPICAL WAVES, SCATTERED MODERATE ISOLATED STRONG IS NOTED  
FROM 00N TO 02.5N BETWEEN 129W AND 138W.  
   
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO  
 
SEE THE SPECIAL FEATURES SECTION ABOVE FOR DETAILS ON A GALE  
WARNING IN EFFECT IN THE GULF OF TEHUANTEPEC FOR THE OVERNIGHT  
HOURS. AN AREA OF 7 TO 9 FT SEAS IS FOUND JUST SOUTHWEST OF THE  
GULF OF TEHUANTEPEC, A COMBINATION OF EARLIER FRESH TO STRONG  
WINDS TO THE EAST NEAR THE GULF OF PAPAGAYO, THE GULF OF  
TEHUANTEPEC WINDS, AND BACKGROUND SW SWELL.  
 
SEE TROPICAL WAVES SECTION ABOVE FOR INFORMATION ON A TROPICAL  
WAVE THAT HAS A POTENTIAL FOR TROPICAL DEVELOPMENT OFFSHORE  
MEXICO AT THE END OF THIS WEEK.  
 
SEAS ARE 4 TO 6 FT ACROSS THE REMAINDER OF THE OFFSHORE WATERS,  
EXCEPT 1 TO 3 FT IN THE GULF OF CALIFORNIA. MODERATE TO FRESH  
NW-N WINDS ARE FOUND OFFSHORE BAJA CALIFORNIA FROM PUNTA EUGENIA  
NORTHWARD, LOCALLY STRONG NEAR PUNTA EUGENIA. WINDS ARE MODERATE  
OR WEAKER ACROSS THE REMAINDER OF THE OFFSHORE WATERS, EXCEPT  
DEVELOPING FRESH TO STRONG WINDS ALONG THE COAST BETWEEN CABO  
CORRIENTES AND THE ENTRANCE TO THE GULF OF CALIFORNIA WHERE A  
STRONG THUNDERSTORM COMPLEX IS IN THE PROCESS OF MOVING SLIGHTLY  
OFFSHORE INTO THE GULF OF CALIFORNIA AND ADJACENT AREAS.  
SCATTERED THUNDERSTORMS ARE NOTED FROM 19N TO 27N BETWEEN MEXICO  
AND 109.5W.  
 
FOR THE FORECAST, THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE  
OVER THE GULF OF AMERICA AND RELATIVELY LOWER PRESSURE SOUTH OF  
MEXICO WILL CONTINUE TO INDUCE PULSES OF STRONG NORTH WINDS OVER  
THE GULF OF TEHUANTEPEC THROUGH WED NIGHT, TO MINIMAL GALE-FORCE  
OVERNIGHT TONIGHT INTO EARLY TUE, WITH MODERATE TO FRESH PULSES  
STARTING THU. SEAS WILL OCCASIONALLY BUILD TO ROUGH WITH THE  
FRESH TO STRONG OR STRONGER WINDS. A SURGE OF STRONG SE WINDS  
WILL MOVE FROM NORTH OF CABO CORRIENTES INTO THE SOUTHERN  
AND CENTRAL GULF OF CALIFORNIA TONIGHT INTO EARLY TUE,  
ASSOCIATED WITH A COMPLEX OF CONVECTION. WINDS AND SEAS MAY BUILD  
ACROSS THE OUTER OFFSHORE WATERS OF SOUTHWESTERN MEXICO BY THE  
END OF THE WEEK INTO THE UPCOMING WEEKEND IN ASSOCIATION WITH A  
POSSIBLY DEVELOPING AREA OF LOW PRESSURE BEYOND THE OFFSHORE  
WATERS.  
 
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,  
AND WITHIN 750 NM OF ECUADOR...  
 
SEE TROPICAL WAVES SECTION ABOVE FOR INFORMATION ON A TROPICAL  
WAVE PRODUCING HEAVY RAINFALL OVER PORTIONS OF COLOMBIA, PANAMA  
AND AREAS NORTHWESTWARD, WITH HEAVY THUNDERSTORMS ALSO OVER THE  
ADJACENT OFFSHORE WATERS AS DESCRIBED ABOVE.  
 
DEVELOPING OFFSHORE EASTERLY FRESH TO STRONG WINDS ARE IN THE  
IMMEDIATE GULF OF PAPAGAYO. WINDS ARE MODERATE OR WEAKER ELSEWHERE  
NORTH OF THE MONSOON TROUGH, AND MODERATE TO FRESH SOUTH OF THE  
MONSOON TROUGH. SEAS ARE 4 TO 7 FT IN LONG-PERIOD SW SWELL,  
EXCEPT 7 TO 9 FT SOUTHWEST OF THE GALAPAGOS ISLANDS.  
 
FOR THE FORECAST, THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE  
OVER THE WESTERN CARIBBEAN AND RELATIVELY LOWER PRESSURE OVER  
CENTRAL AMERICA WILL LEAD TO PULSING STRONG TO NEAR GALE-FROCE  
NORTHEAST TO EAST GAP WINDS OVER THE PAPAGAYO REGION, WITH  
RESULTANT ROUGH SEAS. MODERATE TO FRESH ASSOCIATED WINDS WILL  
EXTEND WELL DOWNWIND ACROSS THE OUTER OFFSHORE WATERS OF EL  
SALVADOR AND GUATEMALA AT TIMES. MODERATE TO FRESH SOUTHERLY  
WINDS WILL PULSE SOUTH OF THE MONSOON TROUGH THROUGH TONIGHT.  
LARGE SOUTHERLY SWELL WILL IMPACT WATERS MAINLY FROM ECUADOR TO  
THE GALAPAGOS ISLANDS THROUGH WED NIGHT, LARGEST EXPECTED THROUGH  
TUE NIGHT.  
   
..REMAINDER OF THE AREA  
 
SEE TROPICAL WAVES SECTION ABOVE FOR INFORMATION ON TWO TROPICAL  
WAVES THAT HAVE POTENTIAL FOR TROPICAL DEVELOPMENT LATER THIS  
WEEK.  
 
MODERATE TO FRESH E WINDS ARE NOTED FROM 09N TO 20N BETWEEN 121W  
AND 136W ASSOCIATED WITH THE TROPICAL WAVE AT 126W, WITH SIMILAR  
WINDS FROM 20N TO 28N BETWEEN 129W AND 138W. MODERATE TO FRESH  
WINDS AND ROUGH SEAS ARE ALSO FOUND SOUTH OF THE MONSOON TROUGH  
BETWEEN 90W AND 126W. WINDS ARE MODERATE OR WEAKER ACROSS THE  
REMAINDER OF THE OPEN WATERS, EXCEPT LOCALLY FRESH NEAR THE  
EASTERN TROPICAL WAVE AT 98W WITH LOCALLY ROUGH SEAS. SEAS ARE 4  
TO 7 FT ACROSS THE REMAINDER OF THE OPEN WATERS. FOR THE  
FORECAST, REGARDLESS OF TROPICAL DEVELOPMENT, THE TROPICAL WAVES  
DESCRIBED IN THE ABOVE SECTION WILL BRING SOME INCREASING WINDS  
AND SEAS TO AREA WATERS. AWAY FROM THESE WAVES, LITTLE CHANGE IS  
EXPECTED IN MARINE WEATHER THROUGH THE WEEK.  
 
 
LEWITSKY  
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