522
AXPZ20 KNHC 231550
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU OCT 23 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
1500 UTC.
..TROPICAL WAVES
A TROPICAL WAVE IS GRADUALLY EXITING CENTRAL AMERICA, AND IS
ALONG 91W, SOUTH OF 17N, MOVING WEST AT 10 TO 15 KT. SCATTERED
MODERATE CONVECTION IS NOTED FROM 10.5N TO 12.5N BETWEEN 86W AND
92W.
A TROPICAL WAVE, WITH AXIS ALONG 109W/110W FROM 08N TO 16N,
MOVING WEST AT 5 TO 10 KT. BROAD LOW PRESSURE HAS FORMED ALONG
THE WAVE NEAR 10.5N109.5W, AND AND IS BEING MONITORED AS INVEST
92E. THIS PATTERN IS PRODUCING DISORGANIZED SHOWERS AND
THUNDERSTORMS FROM 08N TO 16.5N BETWEEN 107W AND 115W.
ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR GRADUAL DEVELOPMENT
OF THIS SYSTEM, AND A TROPICAL DEPRESSION IS LIKELY TO FORM BY
THE END OF THE WEEKEND WHILE IT MOVES GENERALLY WESTWARD AT 10
KT. CURRENTLY THIS SYSTEM HAS A MEDIUM CHANCE OF TROPICAL CYCLONE
FORMATION THROUGH 48 HOURS, AND A HIGH CHANCE THROUGH 7 DAYS.
PLEASE REFER TO THE LATEST NHC TROPICAL WEATHER OUTLOOK AT
WWW.HURRICANES.GOV FOR MORE DETAILS.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH EXTENDS FROM 12N79W TO 07N94W TO 12.5N105W TO
LOW PRESSURE 1009 MB NEAR 10.5N109.5W TO 08.5N130W. THE ITCZ
CONTINUES FROM 08.5N130W TO 13.5N140W. SCATTERED MODERATE
ISOLATED STRONG CONVECTION IS NOTED FROM 05N TO 13.5N EAST OF
102W, FROM 08N TO 15.5N BETWEEN BETWEEN AND EAST OF 80W, FROM
10N TO 14N BETWEEN 108W AND 126W, AND FROM 11.5N TO 16N WEST OF
135W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
A RIDGE ACROSS THE EASTERN SLOPES OF THE SIERRA MADRE MOUNTAINS
OF MEXICO IS SUPPORTING FRESH TO STRONG GAP WINDS ACROSS THE GULF
OF TEHUANTEPEC, WITH ASSOCIATED ROUGH SEAS TO 9 FT. SATELLITE
SCATTEROMETER DATA FROM 0245 UTC SHOWED NEAR-GALE FORCE GAP
WINDS ACROSS THE GULF OF TEHUNATEPEC. FARTHER NORTH, WEAK RIDGING
PERSISTS FROM THE NORTHEAST PACIFIC TO JUST SOUTH OF BAJA
CALIFORNIA SUR. OVERNIGHT SATELLITE SCATTEROMETER DATA SHOWED
MODERATE TO FRESH WINDS OFFSHORE OF THE COAST OF BAJA CALIFORNIA
EAST OF THE HIGH PRESSURE, MAINLY NORTH OF CABO SAN LAZARO.
ALTIMETER DATA DURING THAT TIME ALSO INDICATED 8 TO 10 FT
COMBINED SEAS OFF BAJA CALIFORNIA, LIKELY IN NW SWELL. GENTLE
BREEZES AND SLIGHT TO MODERATE SEAS ARE NOTED ELSEWHERE.
FOR THE FORECAST, THE RIDGE ACROSS THE EASTERN SLOPES OF THE SIERRA
MADRE MOUNTAINS WILL CONTINUE TO SUPPORT STRONG GAP WINDS ACROSS
THE TEHUANTEPEC REGION THROUGH FRI MORNING. FRESH TO STRONG
NORTHERLY WINDS, REACHING NEAR 30 KT, AND MODERATE TO ROUGH SEAS
TO NEAR 9 FT, ARE EXPECTED WITH THIS EVENT DURING THE OVERNIGHT
AND EARLY MORNING HOURS THROUGH MIDDAY FRI. LOOKING AHEAD,
ANOTHER ROUND OF FRESH NORTHERLY GAP WINDS WILL PULSE ACROSS THE
GULF OF TEHUANTEPEC STARTING LATE SUN. ADDITIONAL PULSES OF NW
SWELL WILL CONTINUE TO PROPAGATE ACROSS THE OFFSHORE WATERS OF
BAJA CALIFORNIA THROUGH THE FORECAST PERIOD, SUPPORTING MODERATE
TO ROUGH SEAS INTO FRI, AND THEN AGAIN LATE OVER THE WEEKEND.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
OVERNIGHT SATELLITE SCATTEROMETER DATA SHOWED MODERATE E TO SE
GAP WINDS EXITING THE PAPAGAYO REGION, BEHIND A TROPICAL WAVE
MOVING INTO THE SE MEXICO WATERS. LIGHT TO GENTLE WINDS ARE
ELSEWHERE NORTH OF THE MONSOON TROUGH, ALONG ABOUT 09N, WITH
GENTLE TO MODERATE SW TO W WINDS TO THE SOUTH OF IT. SEAS ARE 4
TO 5 FT, PRIMARILY IN SW SWELL, EXCEPT IN THE LEE OF THE
GALAPAGOS ISLANDS WHERE SLIGHT SEAS PREVAIL. SCATTERED SHOWERS
AND A FEW THUNDERSTORMS ARE ABOUT THE MONSOON TROUGH OFFSHORE OF
COST RICA, AND ALONG THE COAST OF COSTA RICA AND WESTERN PANAMA
TO THE CENTRAL COLOMBIAN COAST.
FOR THE FORECAST, LITTLE CHANGE IN THE WEATHER PATTERN IS
FORECAST, WITH MODERATE S TO SW WINDS AND MODERATE SEAS EXPECTED
SOUTH OF THE MONSOON TROUGH THROUGH EARLY NEXT WEEK. ONSHORE
WESTERLY WIND FLOW IS EXPECTED TO DEVELOP N OF 10N ON SUN AND
CONTINUE INTO EARLY NEXT WEEK, IN RESPONSE TO TROPICAL STORM
MELISSA MOVING SLOWLY ACROSS THE WESTERN CARIBBEAN.
..REMAINDER OF THE AREA
A WEAK RIDGE COVERS THE FORECAST WATERS NORTH OF 15N AND WEST OF
115W, CENTERED ON A 1023 MB HIGH NEAR 35N133W. UNDER THE
INFLUENCE OF THIS SYSTEM, MAINLY LIGHT TO GENTLE WINDS ARE NOTED
NORTH OF 20N AND WEST OF 120W. NW SWELL OF 7 TO 9 FT IS NOTED
NORTH OF 15N BETWEEN 110W AND 130W. SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ARE ACTIVE NEAR A TROUGH ALONG 141W FROM
11N TO 16N AND W OF 135W. THE GRADIENT BETWEEN THIS FEATURE AND
THE RIDGE TO THE NORTH IS SUPPORTING FRESH TO LOCALLY STRONG
WINDS AND SEAS TO 9 FT FROM 13N TO 18N WEST OF 134W. ANOTHER
ROUND OF LARGE NW SWELL IS JUST TO THE NW OF THE LOCAL WATERS,
AND WILL FOLLOW A COLD FRONT EXPECTED TO MOVE ACROSS THE WATERS
NORTH OF 20N THROUGH THE EARLY PART OF NEXT WEEK.
FOR THE FORECAST, THE MAIN FORECAST ISSUE REMAINS THE DEVELOPMENT
AND TRACK OF INVEST 92E BETWEEN 110W AND 130W FROM 10N TO 15N
THROUGH MID WEEK. IN ADDITION, THE GRADIENT BETWEEN THE LOW
PRESSURE AND THE SUBTROPICAL RIDGE TO THE NORTH WILL SUPPORT
FRESH NE WINDS AND 6 TO 7 FT NORTH OF 20N THROUGH THE WEEK. LARGE
NW SWELL WILL ENTER THE NW WATERS LATER THIS MORNING AND
PROPAGATE ACROSS THE REGIONAL WATERS THROUGH THE WEEKEND.
STRIPLING
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