000
AXPZ20 KNHC 101556
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED SEP 10 2025
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
1530 UTC.
..SPECIAL FEATURES
SOUTH OF SOUTHERN AND SOUTHWESTERN MEXICO (EP95):
A TROPICAL WAVE LOCATED A COUPLE HUNDRED MILES OFFSHORE OF THE
COAST OF SOUTHERN MEXICO ALONG 96W IS PRODUCING A LARGE AREA OF
DISORGANIZED SHOWERS AND THUNDERSTORMS, FROM 09N TO 16N BETWEEN
90W AND 104W. ENVIRONMENTAL CONDITIONS ARE FAVORABLE FOR
DEVELOPMENT OF THIS SYSTEM, AND A TROPICAL DEPRESSION IS LIKELY
TO FORM BY LATE THIS WEEK AS IT MOVES WEST-NORTHWESTWARD,
ROUGHLY PARALLEL TO BUT OFFSHORE OF THE MEXICAN COAST. THERE IS A
MEDIUM CHANCE OF TROPICAL FORMATION WITHIN THE NEXT 48 HOURS,
AND A HIGH CHANCE WITHIN THE NEXT 7 DAYS. PLEASE REFER TO THE
LATEST NHC TROPICAL WEATHER OUTLOOK AT WWW.HURRICANES.GOV FOR
MORE DETAILS.
..TROPICAL WAVES
THE AXIS OF A TROPICAL WAVE IS ALONG 96W, EP95, FROM 08N
NORTHWARD INTO SOUTHEASTERN MEXICO, MOVING TOWARD THE WEST AROUND
5 KT. PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE
INFORMATION.
THE AXIS OF A TROPICAL WAVE HAS BEEN REPOSITIONED, AND IS ALONG
128.5W FROM 06N TO 17N. SCATTERED MODERATE CONVECTION IS
OCCURRING FROM 09N TO 17N BETWEEN 120W AND 132W.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH AXIS EXTENDS FROM 10.5N86W TO 14N102W TO A
1011 MB LOW NEAR 13N128.5W TO 10N134W. THE ITCZ CONTINUES FROM
10N134W TO BEYOND 09.5N140W. SCATTERED MODERATE CONVECTION IS
OCCURRING FROM 04N TO 13N EAST OF 89W AND FROM 10N TO 15N BETWEEN
105N AND 116W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
NUMEROUS STRONG THUNDERSTORMS ARE OCCURRING OFFSHORE OF WEST-
CENTRAL MEXICO FROM SINALOA TO JALISCO, AND GUSTY WINDS AND
RAPIDLY BUILDING SEAS ARE LIKELY NEAR THIS ACTIVITY. A COLD FRONT
EXTENDS FROM THE CALIFORNIA AND ARIZONA BORDER SOUTHWESTWARD
THROUGH BAJA CALIFORNIA NORTE TO 24N130W, AND A SURFACE TROUGH
HAS BEEN ANALYZED ALONG THE BAJA PENINSULA TO 21N109W. THE
PRESSURE GRADIENT BETWEEN THESE FEATURES IS SUPPORTING MODERATE
TO FRESH NW WINDS AND MODERATE SEAS OVER THE BAJA CALIFORNIA
WATERS. ELSEWHERE, MODERATE TO FRESH NE TO SE WINDS AND MODERATE
SEAS ARE NOTED OFFSHORE OF SOUTHERN MEXICO NEAR A TROPICAL WAVE
ALONG 96W. MODERATE OR WEAKER WINDS ARE FOUND OVER THE REMAINDER
OF THE MEXICO WATERS. SEAS OF 4 TO 6 FT ARE NOTED OFFSHORE OF
SOUTHWESTERN MEXICO, WITH 1 TO 2 FT SEAS FOUND IN THE GULF OF
CALIFORNIA.
FOR THE FORECAST, MODERATE TO OCCASIONALLY FRESH NW WINDS ARE
EXPECTED OVER THE BAJA CALIFORNIA WATERS INTO THIS WEEKEND AS A
COLD FRONT DISSIPATES OVER THE REGION AND A MODERATE PRESSURE
GRADIENT DEVELOPS BETWEEN TROUGHING OVER THE GULF OF CALIFORNIA
AND BUILDING HIGH PRESSURE IN THE EASTERN PACIFIC. ELSEWHERE,
FRESH TO STRONG N TO NE GAP WINDS ARE EXPECTED IN THE GULF OF
TEHUANTEPEC THU THROUGH THIS WEEKEND. LOOKING AHEAD, A TROPICAL
WAVE LOCATED A COUPLE HUNDRED MILES OFFSHORE OF THE COAST OF
SOUTHERN MEXICO WILL MOVE WESTWARD THIS WEEK, AND INCREASING
WINDS AND BUILDING SEAS ARE EXPECTED NEAR THIS WAVE.
ENVIRONMENTAL CONDITIONS ARE FAVORABLE FOR DEVELOPMENT OF THIS
SYSTEM, AND A TROPICAL DEPRESSION IS LIKELY TO FORM BY LATE THIS
WEEK AS IT MOVES WEST-NORTHWESTWARD, ROUGHLY PARALLEL TO BUT
OFFSHORE OF THE MEXICAN COAST. THERE IS A MEDIUM CHANCE OF
TROPICAL DEVELOPMENT WITHIN THE NEXT 48 HOURS, AND A HIGH CHANCE
WITHIN THE NEXT 7 DAYS.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
MODERATE TO LOCALLY FRESH SE TO SW WINDS AND 5 TO 7 FT SEAS ARE
OCCURRING OFFSHORE OF GUATEMALA IN THE WAKE OF A TROPICAL WAVE
ALONG 96W. SOUTH OF THE MONSOON TROUGH, MODERATE TO LOCALLY FRESH
SE TO SW WINDS ARE NOTED. SEAS OF 4 TO 6 FT ARE NOTED OVER THE
CENTRAL AND SOUTH AMERICAN WATERS, WITH SEAS TO 7 FT OCCURRING
SOUTH OF THE GALAPAGOS ISLANDS.
FOR THE FORECAST, MODERATE TO OCCASIONALLY FRESH SE TO SW WINDS
WILL OCCUR OVER THE GUATEMALA WATERS INTO EARLY THU AS A TROPICAL
WAVE LOCATED ALONG 96W MOVES WESTWARD. ELSEWHERE, MODERATE NE TO
E GAP WINDS WILL PULSE IN THE GULF OF PAPAGAYO THU INTO FRI.
MODERATE TO OCCASIONALLY FRESH SE TO SW WINDS WILL PREVAIL SOUTH
OF THE MONSOON TROUGH THROUGH THIS WEEKEND. LOOKING AHEAD, A
LONG-PERIOD SOUTHERN HEMISPHERE SWELL WILL MOVE THROUGH THE
REGIONAL WATERS THIS WEEKEND, LEADING TO ROUGH SEAS OFFSHORE OF
SOUTH AMERICA THIS WEEKEND, AND OVER THE CENTRAL AMERICA WATERS
BY EARLY NEXT WEEK.
..REMAINDER OF THE AREA
A TROPICAL WAVE AXIS HAS BEEN ANALYZED ALONG 128.5W, AND
MODERATE TO FRESH NE TO E WINDS AND MODERATE SEAS ARE NOTED NEAR
THIS WAVE. ELSEWHERE, A COLD FRONT EXTENDS FROM THE CALIFORNIA
AND ARIZONA BORDER SOUTHWESTWARD THROUGH BAJA CALIFORNIA NORTE TO
24N130W, AND RIDGING IS BUILDING IN THE WAKE OF THIS FRONT. THE
PRESSURE GRADIENT BETWEEN ALL OF THESE FEATURES IS SUPPORTING
MODERATE TO FRESH NE WINDS AND 5 TO 7 FT SEAS NORTH OF THE
MONSOON TROUGH AND ITCZ TO 25N, GENERALLY WEST OF 120W. MODERATE
OR WEAKER WINDS AND 4 TO 5 FT SEAS PREVAIL FARTHER NORTH. SOUTH
OF THE MONSOON TROUGH AND ITCZ, MODERATE TO FRESH S TO SE WINDS
ARE NOTED. RECENT ALTIMETER SATELLITE DATA SHOW 5 TO 7 FT SEAS
PREVAIL OVER THE SOUTHERN WATERS, WITH LOCALLY ROUGH SEAS NOTED
AROUND 10N BETWEEN 105W AND 110W.
FOR THE FORECAST, FRESH NE TO SE WINDS AND BUILDING SEAS ARE
EXPECTED AS A TROPICAL WAVE CURRENTLY ALONG 128.5W MOVES WESTWARD
THIS WEEK. FARTHER NORTH, THE COLD FRONT WILL GRADUALLY DISSIPATE
BY LATE WEEK, AND HIGH PRESSURE WILL BUILD OVER THE EASTERN
PACIFIC. AN INCREASING PRESSURE GRADIENT BETWEEN THIS HIGH, THE
TROPICAL WAVE AND THE MONSOON TROUGH AND ITCZ WILL LEAD TO FRESH
NE WINDS AND ROUGH SEAS FROM 15N TO 20N WEST OF 130W TONIGHT
THROUGH FRI. SOUTH OF THE MONSOON TROUGH AND ITCZ, MODERATE TO
FRESH SE TO SW WINDS ARE EXPECTED THROUGH THIS WEEKEND. ROUGH
SEAS ALONG 10N WILL SLOWLY SUBSIDE THROUGH THU MORNING. LOOKING
AHEAD, A LONG-PERIOD SOUTHERN HEMISPHERE SWELL WILL PROMOTE ROUGH
SEAS OVER THE EQUATORIAL WATERS BY THIS WEEKEND, WITH ROUGH SEAS
EXPANDING FARTHER NORTH EARLY NEXT WEEK.
ADAMS
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