826
AXPZ20 KNHC 172206
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU SEP 17 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2145 UTC.
..SPECIAL FEATURES
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.
THE AXIS OF A TROPICAL WAVE IS NEAR 115.5W FROM 07N TO 18N,
WITH LOW PRESSURE OF 1009 MB NEAR 12N115.5W. IT IS MOVING
WESTWARD AT ABOUT 10 KT. SATELLITE IMAGERY REVEALS SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION BETWEEN THE WAVE AND
118W, AND ALSO FROM 11N TO 14N BETWEEN 111W AND 116W. ENVIRONMENTAL
CONDITIONS APPEAR CONDUCIVE FOR ADDITIONAL DEVELOPMENT, 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. PLEASE REFER TO THE LATEST NHC TROPICAL WEATHER OUTLOOK
AT WEBSITE: WWW.HURRICANES.GOV FOR MORE DETAILS.
..TROPICAL WAVES
A TROPICAL WAVE HAS IS ITS AXIS ALONG 99W FROM 05N NORTHWARD TO
EXTREME SOUTHERN MEXICO NEAR ACAPULCO. IT IS MOVING WESTWARD AT
AROUND 10 TO 15 KT. NUMEROUS MODERATE TO ISOLATED STRONG
CONVECTION IS SEEN FROM 08N TO 13N BETWEEN 94W AND 100W. 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 GRADUAL
DEVELOPMENT, AND A TROPICAL DEPRESSION IS LIKELY TO FORM LATE
THIS WEEKEND OR EARLY NEXT WEEK WHILE IT GRADUALLY MOVES
NORTHWESTWARD AND THEN NORTHWARD OFF THE COAST OF SOUTHWESTERN
MEXICO.
THE AXIS OF A TROPICAL WAVE IS NEAR 115.5W FROM 07N TO 18N,
MOVING WESTWARD AT 10 TO 15 KT. SEE THE SPECIAL FEATURES SECTION
ABOVE FOR RELATED INFORMATION.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH AXIS EXTENDS FROM ALONG THE COAST OF NORTHWEST
COLOMBIA WEST-SOUTHWEST TO ACROSS THE COSTA RICA/PANAMANIAN
BORDER, THEN TO 09N84W TO 07N1OOW TO 09N110W TO LOW PRESSURE,
INVEST EP98, NEAR 12N115.5W 1009 MB AND TO 12N124W. NUMEROUS
MODERATE TO ISOLATED STRONG CONVECITON IS FROM 08N TO 13N BETWEEN
100W-106W, AND FROM 06N TO 09N BETWEEN 118W-124W. SCATTERED
MODERATE CONVECTION IS WITHIN 120 NM SOUTH OF THE TROUGH BETWEEN
91W-95W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
PLEASE SEE SPECIAL FEATURES SECTION ABOVE FOR DETAILS ON A GALE
WARNING FOR THE GULF OF TEHUANTEPEC.
MOSTLY GENTLE TO MODERATE NORTHWEST WINDS ACROSS THE CENTRAL AND
SOUTHERN SECTIONS OF THE GULF OF CALIFORNIA WHILE LIGHT AND
VARIABLE WINDS ARE OVER THE NORTHERN PORTION OF THE GULF. 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 FOR THE GULF OF TEHUANTEPEC.
GENTLE TO MODERATE BREEZES AND MODERATE SEAS WILL PERSIST INTO
THE WEEKEND OVER THE REGIONAL MEXICAN WATERS. THE EXCEPTION IS
ALONG AND OFFSHORE THE NORTHERN AND CENTRAL PORTIONS OF BAJA
CALIFORNIA, WHERE NORTHWEST WINDS WILL PULSE AT FRESH TO LOCALLY
STRONG SPEEDS INTO SAT NIGHT. SEAS OF 4 TO 7 FT ARE EXPECTED
OVER THESE WATERS THROUGH THE WEEKEND. MEANWHILE, A TROPICAL WAVE
LOCATED TO THE SOUTHEAST OF OF ACAPULCO, MEXICO IS PRODUCING
DISORGANIZED SHOWERS AND THUNDERSTORMS OVER THE OUTER OFFSHORE
WATERS OF THE STATES OF GUERRERO AND OAXACA. LOOKING AHEAD,
ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR GRADUAL
DEVELOPMENT, AND A TROPICAL DEPRESSION IS LIKELY TO FORM LATE
THIS WEEKEND OR EARLY NEXT WEEK WHILE IT MOVES GRADUALLY
NORTHWESTWARD AND THEN NORTHWARD OFF THE COAST OF SOUTHWESTERN
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 1006 MB REMNANT LOW OF TROPICAL DEPRESSION FIFTEEN-E IS
LOCATED NEAR 15N133W. A 1912Z 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 LATEST SCATTEROMETER SATELLITE ALTIMETER DATA.
SATELLITE IMAGERY SHOWS NUMEROUS ISOLATED STRONG CONVECTION FROM
14N TO 18N BETWEEN 129W AND 136W. SCATTERED MODERATE TO ISOLATED
STRONG CONVECTION IS PRESENT FROM 02N TOM 07N BETWEEN 125W AND
132W AND FROM 14N TO 20N BETWEEN 120W AND 129W.
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 115.5W, AND A
TROPICAL DEPRESSION IS LIKELY TO FORM THIS WEEKEND OR EARLY NEXT
WEEK AS IT MOVES WESTWARD ACROSS THE WESTERN PART OF THE EASTERN
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 THAT IS NEAR 99W.
AGUIRRE
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