475
AXPZ20 KNHC 131605
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT SEP 13 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.
..TROPICAL WAVES
THE AXIS OF A TROPICAL WAVE IS ALONG 87W, FROM 01N NORTHWARD
THROUGH WESTERN NICARAGUA AND CENTRAL HONDURAS INTO THE WESTERN
CARIBBEAN SEA. THE WAVE IS MOVING WESTWARD AROUND 10 KT.
CONVECTION ASSOCIATED WITH THIS WAVE IS DESCRIBED IN THE
ITCZ/MONSOON TROUGH SECTION BELOW.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH AXIS EXTENDS FROM 09N78.5W TO 16N110W TO
BEYOND 13N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION
IS NOTED FROM 09N TO 24N BETWEEN 105W AND 112W. SCATTERED
MODERATE CONVECTION IS OCCURRING FROM 04N TO 10N EAST OF 87W,
FROM 05N TO 16N BETWEEN 91W AND 100W, FROM 13N TO 16N BETWEEN
118W AND 120W, AND FROM 09N TO 14N BETWEEN 127W AND 140W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
THE REMNANTS OF FORMER TROPICAL STORM MARIO ARE PRODUCING
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION OFF THE COAST OF
WEST-CENTRAL MEXICO NEAR SINALOA AND NAYARIT. MODERATE TO
LOCALLY FRESH NE TO SE WINDS ARE OCCURRING NORTH AND EAST OF THE
REMNANT TROUGH, AND RECENT ALTIMETER SATELLITE DATA SHOW 5 TO 7
FT SEAS IN THIS REGION. ELSEWHERE, MODERATE TO FRESH N TO NE
WINDS ARE NOTED IN THE GULF OF TEHUANTEPEC AS HIGH PRESSURE
BUILDS OVER EAST-CENTRAL MEXICO. OFFSHORE OF BAJA CALIFORNIA, THE
PRESSURE GRADIENT BETWEEN A SURFACE TROUGH IN THE GULF OF
CALIFORNIA AND HIGH PRESSURE TO THE WEST IS SUPPORTING MODERATE
TO FRESH NW WINDS AND 5 TO 7 FT SEAS. GENTLE TO MODERATE WINDS
AND 1 TO 3 FT SEAS PREVAIL IN THE GULF OF CALIFORNIA.
FOR THE FORECAST, MODERATE TO LOCALLY FRESH WINDS ARE EXPECTED
OFFSHORE OF WEST-CENTRAL MEXICO AND NEAR THE REVILLAGIGEDO
ISLANDS THIS WEEKEND AS THE REMNANTS OF FORMER TROPICAL STORM
MARIO SLOWLY DISSIPATE. ELSEWHERE, FRESH N TO NE WINDS WILL
PULSE IN THE GULF OF TEHUANTEPEC THIS MORNING, WITH FRESH TO
LOCALLY STRONG NE WINDS EXPECTED TONIGHT INTO EARLY SUN. MODERATE
TO OCCASIONALLY FRESH NE WINDS ARE EXPECTED THEREAFTER, WITH
WINDS INCREASING TO STRONG SPEEDS BY THE MIDDLE OF NEXT WEEK.
MODERATE TO FRESH NW WINDS OFFSHORE OF BAJA CALIFORNIA WILL
DIMINISH SLIGHTLY SUN INTO NEXT WEEK. LOOKING AHEAD, AN AREA OF
LOW PRESSURE COULD DEVELOP WELL OFFSHORE OF THE COAST OF SOUTHERN
OR SOUTHWESTERN MEXICO EARLY NEXT WEEK. ENVIRONMENTAL CONDITIONS
ARE EXPECTED TO BE CONDUCIVE FOR GRADUAL DEVELOPMENT THEREAFTER,
AS THE LOW TRACKS WESTWARD TO WEST-NORTHWESTWARD AROUND 10 TO 15
MPH. ANOTHER AREA OF LOW PRESSURE COULD DEVELOP SOUTH OF THE
BAJA CALIFORNIA PENINSULA OVER THE NEXT DAY OR TWO. ENVIRONMENTAL
CONDITIONS ARE EXPECTED TO BE CONDUCIVE FOR GRADUAL DEVELOPMENT
THEREAFTER, AS THE LOW TRACKS SLOWLY WESTWARD. BOTH OF THESE
SYSTEMS HAVE A LOW CHANCE OF TROPICAL DEVELOPMENT WITHIN THE NEXT
7 DAYS.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
MODERATE TO LOCALLY FRESH S WINDS ARE OCCURRING SOUTH OF THE
MONSOON TROUGH, WITH GENTLE TO LOCALLY MODERATE WINDS NOTED TO
THE NORTH. RECENT ALTIMETER SATELLITE DATA SHOW 5 TO 7 FT SEAS
PREVAIL OVER THE REGIONAL WATERS.
FOR THE FORECAST, A LONG-PERIOD SOUTHERN HEMISPHERE SWELL WILL
MOVE THROUGH THE CENTRAL AND SOUTH AMERICAN WATERS THIS WEEKEND,
LEADING TO ROUGH SEAS OFFSHORE OF ECUADOR BY THIS EVENING, AND
OFFSHORE OF COLOMBIA THROUGH COSTA RICA SUN INTO EARLY NEXT WEEK.
SEAS WILL SLOWLY SUBSIDE REGION-WIDE MON INTO TUE, THOUGH
ADDITIONAL ROUGH SEAS WILL BE POSSIBLE BETWEEN THE GALAPAGOS
ISLANDS AND ECUADOR AROUND MIDWEEK. OTHERWISE, MODERATE TO
OCCASIONALLY FRESH S TO SW WINDS WILL PREVAIL SOUTH OF THE
MONSOON TROUGH THROUGH NEXT WEEK. LOOKING AHEAD, OCCASIONAL
MODERATE TO FRESH NE GAP WINDS WILL BE POSSIBLE IN THE GULF OF
PAPAGAYO BY THE MIDDLE OF NEXT WEEK.
..REMAINDER OF THE AREA
RIDGING DOMINATES THE EASTERN PACIFIC WATERS NORTH OF THE
MONSOON TROUGH, WITH GENTLE TO LOCALLY MODERATE N TO NE WINDS
FOUND NORTH OF 25N AND WEST OF 125W. A MODERATE PRESSURE GRADIENT
BETWEEN THIS RIDGE AND THE MONSOON TROUGH IS SUPPORTING MODERATE
TO LOCALLY FRESH NE WINDS FARTHER SOUTH AND TO THE WEST OF 120W.
RECENT ALTIMETER DATA SHOW 5 TO 7 FT SEAS IN THIS REGION, WITH
LOCALLY ROUGH SEAS OCCURRING NEAR CONVECTION ALONG THE MONSOON
TROUGH. ELSEWHERE, A LONG-PERIOD SOUTHERN HEMISPHERE SWELL IS
SUPPORTING ROUGH SEAS SOUTH OF THE EQUATOR. MODERATE TO LOCALLY
FRESH S TO SE WINDS AND 5 TO 7 FT SEAS PREVAIL ELSEWHERE SOUTH OF
THE MONSOON TROUGH.
FOR THE FORECAST, A LONG-PERIOD SOUTHERN HEMISPHERE SWELL WILL
PROPAGATE NORTHWARD THIS WEEKEND, SUPPORTING ROUGH SEAS SOUTH OF
05N BETWEEN 90W AND 120W BY TONIGHT, AND SOUTH OF 15N ON SUN.
ROUGH SEAS WILL DIMINISH SOUTH OF 05N EARLY NEXT WEEK, WITH ROUGH
SEAS PERSISTING FARTHER NORTH THROUGH THE MIDDLE OF NEXT WEEK.
ELSEWHERE, FRESH TO LOCALLY STRONG WINDS ARE EXPECTED WITHIN 120
NM ON BOTH SIDES OF THE MONSOON TROUGH AND ITCZ GENERALLY BETWEEN
105W AND 130W SUN THROUGH EARLY NEXT WEEK. OTHERWISE, MODERATE TO
LOCALLY FRESH WINDS ARE EXPECTED ELSEWHERE IN THE TRADE WIND
WATERS THROUGH NEXT WEEK.
ADAMS
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