500
AXPZ20 KNHC 092200
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE SEP 9 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2130 UTC.
..SPECIAL FEATURES
A TROPICAL WAVE LOCATED SOUTH OF THE SOUTHERN COAST OF GUATEMALA
IS PRODUCING A LARGE AREA OF DISORGANIZED SHOWERS AND
THUNDERSTORMS FROM 09N TO 16N BETWEEN 88W AND 103W. 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.
..TROPICAL WAVES
THE AXIS OF A TROPICAL WAVE IS ALONG 94W FROM 08N NORTHWARD INTO
SOUTHEASTERN MEXICO, MOVING TOWARD THE WEST AROUND 10 KT. PLEASE
SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION.
THE AXIS OF A TROPICAL WAVE IS ALONG ALONG 123.5W FROM 08N TO
18N, MOVING TOWARD THE WEST AROUND 15 KT. SCATTERED MODERATE TO
ISOLATED STRONG CONVECTION IS OBSERVED FROM 10N TO 14N BETWEEN
123W AND 131W.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH EXTENDS FROM 07N78W TO 16N122W TO 12N127W.
THE ITCZ CONTINUES FROM 12N127W TO BEYOND 09N140W. SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION IS NOTED FROM 09N TO 14N
BETWEEN 105W AND 114W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
SCATTERED MODERATE TO STRONG THUNDERSTORMS ARE OCCURRING OFF THE
WEST COAST OF MEXICO FROM SINALOA THROUGH GUERRERO, AND GUSTY
AND ERRATIC WINDS AND RAPIDLY BUILDING SEAS ARE LIKELY NEAR THIS
ACTIVITY. AN INCREASING PRESSURE GRADIENT BETWEEN A SURFACE
TROUGH ANALYZED OVER THE GULF OF CALIFORNIA AND A COLD FRONT
APPROACHING FROM THE NORTHWEST IS LEADING TO MODERATE TO FRESH NW
WINDS OFFSHORE OF BAJA CALIFORNIA, AS OBSERVED VIA SCATTEROMETER
SATELLITE DATA. RECENT ALTIMETER DATA SHOW 4 TO 6 FT SEAS IN
THIS REGION. ELSEWHERE, MODERATE NE WINDS AND MODERATE SEAS ARE
NOTED IN THE GULF OF TEHUANTEPEC. OTHERWISE, MODERATE OR WEAKER
WINDS PREVAIL OVER THE REMAINDER OF THE MEXICO OFFSHORE WATERS.
SEAS OF 4 TO 6 FT ARE NOTED OFFSHORE OF SOUTHERN MEXICO, WITH 1
TO 3 FT SEAS IN THE GULF OF CALIFORNIA.
FOR THE FORECAST, MODERATE TO FRESH NW WINDS WILL OCCUR OVER THE
BAJA CALIFORNIA WATERS THIS WEEK AS THE PRESSURE GRADIENT
PREVAILS BETWEEN A WEAKENING COLD FRONT APPROACHING THE REGION
FROM THE NORTHWEST AND A SURFACE TROUGH IN THE GULF OF
CALIFORNIA. LOCALLY STRONG WINDS WILL BE POSSIBLE IN THE
SEBASTIAN VIZCAINO BAY INTO EARLY WED. ELSEWHERE, OCCASIONALLY
FRESH NE WINDS WILL PULSE IN THE GULF OF TEHUANTEPEC THU INTO
THIS WEEKEND. LOOKING AHEAD, A TROPICAL WAVE LOCATED SOUTH OF THE
SOUTHERN COAST OF GUATEMALA IS PRODUCING A LARGE AREA OF
DISORGANIZED SHOWERS AND THUNDERSTORMS. 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...
RECENT SCATTEROMETER DATA SHOW MODERATE TO FRESH E WINDS AND 5
TO 7 FT SEAS ARE OCCURRING OFFSHORE OF GUATEMALA AND EL SALVADOR
IN THE WAKE OF A TROPICAL WAVE ANALYZED ALONG 94W. GENTLE WINDS
AND 4 TO 6 FT SEAS ARE NOTED ELSEWHERE NORTH OF THE MONSOON
TROUGH. TO THE SOUTH, MODERATE SE TO SW WINDS AND 5 TO 7 FT SEAS
IN MIXED S AND SW SWELL PREVAIL.
FOR THE FORECAST, MODERATE TO FRESH SE TO S WINDS AND MODERATE
SEAS WILL OCCUR OVER THE WATERS OFFSHORE OF EL SALVADOR AND
GUATEMALA THROUGH WED MORNING IN THE WAKE OF A TROPICAL WAVE
MOVING WESTWARD OFFSHORE OF SOUTHERN MEXICO. ELSEWHERE, MODERATE
TO LOCALLY FRESH SE TO SW WINDS AND MODERATE SEAS IN SW SWELL
WILL OCCUR SOUTH OF THE MONSOON TROUGH THIS WEEK. MODERATE NE GAP
WINDS WILL PULSE IN THE GULF OF PAPAGAYO BY LATE WEEK. LOOKING
AHEAD, A LONG-PERIOD SW SWELL WILL LEAD TO ROUGH SEAS OVER THE
SOUTH AMERICA WATERS THIS WEEKEND.
..REMAINDER OF THE AREA
MODERATE TO LOCALLY FRESH N TO NE WINDS ARE OCCURRING NEAR AND
TO THE WEST OF A TROPICAL WAVE ANALYZED ALONG 123.5W. FARTHER
NORTH, A COLD FRONT EXTENDS FROM 30N123W TO 28N130W TO 28N140W,
AND LOCALLY MODERATE N WINDS ARE OCCURRING IN THE WAKE OF THE
FRONT, AS OBSERVED VIA SCATTEROMETER DATA. ELSEWHERE NORTH OF THE
MONSOON TROUGH, THE PRESSURE GRADIENT BETWEEN THE AFOREMENTIONED
COLD FRONT AND THE MONSOON TROUGH AND ITCZ IS LEADING TO
MODERATE TO LOCALLY FRESH E TO NE WINDS. RECENT ALTIMETER
SATELLITE DATA SHOW 4 TO 7 FT SEAS IN THIS REGION. SOUTH OF THE
MONSOON TROUGH AND ITCZ, MODERATE TO FRESH SE TO SW WINDS
PREVAIL. LOCALLY ROUGH SEAS ARE NOTED FROM 05N TO 10N BETWEEN
100W AND 112W, WITH GENERALLY MODERATE SEAS NOTED ELSEWHERE SOUTH
OF 10N.
FOR THE FORECAST, A TROPICAL WAVE ANALYZED ALONG 123.5W WILL
PROGRESS TOWARD THE WEST THIS WEEK, LEADING TO MODERATE TO FRESH
NE TO SE WINDS AND BUILDING SEAS SURROUNDING THE WAVE. FARTHER
NORTH, THE AFOREMENTIONED COLD FRONT WILL GRADUALLY DECAY OVER
THE NORTHERN WATERS THROUGH MIDWEEK. THE INCREASING PRESSURE
GRADIENT BETWEEN THIS FRONT, 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 LATE THIS WEEK. SOUTH OF THE MONSOON
TROUGH AND ITCZ, MODERATE TO OCCASIONALLY FRESH SE TO SW WINDS
WILL PREVAIL. LOCALLY ROUGH SEAS FROM 05N TO 10N BETWEEN 100W AND
112W WILL SLOWLY SUBSIDE THROUGH WED MORNING. LOOKING AHEAD, A
LONG-PERIOD SW SWELL WILL LEAD TO ROUGH SEAS OVER THE EQUATORIAL
WATERS BY THIS WEEKEND.
ADAMS
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