243
AXPZ20 KNHC 231553
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN AUG 23 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1500 UTC.
..SPECIAL FEATURES
TROPICAL STORM ISELLE FORMS TODAY WELL OFFSHORE OF MEXICO. IT IS
CENTERED NEAR 15.3N 114.2W AT 23/1500 UTC, MOVING WEST-NORTHWEST
AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM
SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. NUMEROUS
MODERATE TO STRONG CONVECTION IS NOTED WITHIN 180 NM W SEMICIRCLE
AND 90 NM E SEMICIRCLE OF CENTER. A NORTHWESTWARD MOTION IS
EXPECTED THROUGH MONDAY, FOLLOWED BY A GRADUAL TURN BACK TOWARD
THE WEST- NORTHWEST ON TUESDAY. SOME STRENGTHENING IS FORECAST
DURING THE NEXT COUPLE OF DAYS, AND ISELLE COULD BECOME A
HURRICANE LATE MONDAY OR EARLY TUESDAY. THE OUTER PERIPHERY OF
ISELLE WILL BRING STRONG WINDS AND ROUGH SEAS TO THE
REVILLAGIGEDO ISLANDS TODAY. TROPICAL STORM CONDITIONS ARE
POSSIBLE TODAY, AND STORM CONDITIONS ARE EXPECTED TONIGHT.
PLEASE READ THE LATEST HIGH SEAS FORECAST ISSUED
BY THE NATIONAL HURRICANE CENTER AT WEBSITE -
HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIAHSFEP2.SHTML AND THE LATEST
ISELLE NHC FORECAST/ADVISORY AND PUBLIC ADVISORY AT
WWW.HURRICANES.GOV FOR MORE DETAILS.
CENTRAL EAST PACIFIC (EP91): DISORGANIZED SHOWERS AND THUNDERSTORMS
ARE PERSISTING WITH A BROAD AREA OF LOW PRESSURE LOCATED WELL TO
THE SOUTH-SOUTHWEST OF THE SOUTHERN TIP OF THE BAJA CALIFORNIA
PENINSULA. ENVIRONMENTAL CONDITIONS COULD SUPPORT THE DEVELOPMENT
OF A SHORT-LIVED TROPICAL DEPRESSION DURING THE NEXT DAY OR TWO
BEFORE IT INTERACTS OR MERGES WITH T.S. ISELLE. THIS SYSTEM HAS
A MEDIUM CHANCE FOR TROPICAL CYCLONE FORMATION THROUGH 48 HRS,
AND ALSO THROUGH 7 DAYS.
PLEASE REFER TO THE LATEST NHC TROPICAL WEATHER OUTLOOK AT
WEBSITE: HTTPS://WWW.NHC.NOAA.GOV/TEXT/MIATWOEP.SHTML FOR MORE
DETAILS ON THESE SYSTEMS.
..TROPICAL WAVES
A TROPICAL WAVE IS ALONG 86W/87W FROM 04N TO 20N MOVING WESTWARD
AT 15 KT. A CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION IS
NOTED FROM 10N TO 12N BETWEEN 80W AND 85W. THIS CONVECTIVE
ACTIVITY IS AFFECTING SOUTHERN NICARAGUA AND NORTHERN COSTA
RICA.
A TROPICAL WAVE IS ALONG 100W N OF 04N TO NEAR ACAPULCO, MEXICO,
MOVING WESTWARD AT 15 KT. SCATTERED MODERATE TO ISOLATED STRONG
CONVECTION IS OBSERVED FROM 10N TO 16N BETWEEN 96W AND 105W.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH EXTENDS FROM 09N84W TO 07N100W TO 15N110W TO
10N123W TO BEYOND 06N140W. ASIDE FROM THE CONVECTION RELATED TO
THE TROPICAL WAVES, INVEST AREA EP91 AND T.S. ISELLE DESCRIBED
ABOVE, SCATTERED MODERATE TO ISOLATED STRONG CONVECTION CAN BE
FOUND FROM 06N TO 13N BETWEEN 90W AND 97W, AND FROM 03N TO 10N W
OF 130W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION
ABOUT RECENTLY UPGRADED T.S. ISELLE AND INVEST AREA EP91.
A RIDGE CONTINUES TO DOMINATE THE OFFSHORE FORECAST WATERS OF
BAJA CALIFORNIA NORTE SUPPORTING GENTLE TO MODERATE NW WINDS AND
MODERATE SEAS. WINDS AND SEAS ASSOCIATED WITH THE OUTER PERIPHERY
OF T.S. ISELLE ARE REACHING THE REVILLAGIGEDO ISLANDS. GENTLE TO
MODERATE SE TO S WINDS ARE OCCURRING IN THE GULF OF CALIFORNIA
WITH SLIGHT TO MODERATE SEAS. THE HIGHEST SEAS ARE NEAR THE
ENTRANCE TO THE GULF. FRESH TO STRONG N GAP WINDS ARE ACROSS THE
GULF OF TEHUANTEPEC REGION AND DOWNWIND TO ABOUT 14N. SEAS ARE
UP TO 8 FT WITH THESE WINDS.
FOR THE FORECAST, TROPICAL STORM ISELLE WILL MOVE TO 16.5N
115.6W THIS EVENING, 17.9N 117.2W MON MORNING, STRENGTHEN TO A
HURRICANE NEAR 19.3N 118.7W MON EVENING, 20.5N 120.3W TUE
MORNING, WEAKEN TO A TROPICAL STORM NEAR 21.4N 121.9W TUE
EVENING, AND 22.0N 123.6W WED MORNING. ISELLE WILL CHANGE LITTLE
IN INTENSITY AS IT MOVES TO NEAR 23.0N 127.2W EARLY THU. FRESH
NORTHERLY GAP WINDS WILL CONTINUE TO PULSE TO STRONG SPEEDS OVER
THE GULF OF TEHUANTEPEC DURING THE OVERNIGHT INTO THE EARLY
MORNING HOURS THROUGH THE NEXT SEVERAL DAYS, WITH SEAS OCCASIONALLY
BUILDING TO 8 FT. A RIDGE WILL CONTINUE TO DOMINATE THE OFFSHORE
FORECAST WATERS OF BAJA CALIFORNIA NORTE TODAY, SUPPORTING
MAINLY GENTLE TO MODERATE WINDS. SOUTHERLY WIND FLOW WILL BECOME
FRESH TO LOCALLY STRONG OVER THE NORTH AND CENTRAL PARTS OF THE
GULF OF CALIFORNIA TODAY.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
FRESH TO STRONG NE TO E GAP WINDS CONTINUE ACROSS THE PAPAGAYO
REGION AND DOWNWIND TO NEAR 91W, WHERE SEAS ARE 6 TO 8 FT.
MODERATE OR WEAKER WINDS ARE FOUND ELSEWHERE, WITH MODERATE SEAS
IN S SWELL.
FOR THE FORECAST, HIGH PRESSURE WILL PERSIST OVER THE EASTERN GULF
OF AMERICA AND NORTHWESTERN CARIBBEAN INTO EARLY NEXT WEEK, LEADING
TO FRESH NE TO E GAP WINDS PULSING TO STRONG SPEEDS OVER THE PAPAGAYO
REGION EACH EVENING AND NIGHT. MODERATE TO FRESH WINDS EXTENDING
WELL DOWNWIND OF PAPAGAYO WILL IMPACT THE OUTER WATERS OFFSHORE
OF EL SALVADOR AND GUATEMALA THROUGH THE MIDDLE OF THE WEEK. SOUTH
OF THE MONSOON TROUGH, GENTLE TO LOCALLY MODERATE WINDS WILL PERSIST
THROUGH WED NIGHT. MAINLY MODERATE SEAS WILL PREVAIL AWAY FROM THE
GULF OF PAPAGAYO THROUGH THE FORECAST PERIOD.
..REMAINDER OF THE AREA
PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION ABOUT
RECENTLY UPGRADED T.S. ISELLE AND THE INVEST AREA EP91.
HIGH PRESSURE OF 1024 MB LOCATED NEAR 42N133W EXTENDS A RIDGE
SOUTHEASTWARD INTO THE NORTHERN FORECAST WATERS TO OFFSHORE OF
BAJA CALIFORNIA NORTE, SUPPORTING MODERATE TO LOCALLY FRESH NE TO
E WINDS FROM 10N TO 26N W OF 130W. MODERATE OR WEAKER WINDS AND
MODERATE SEAS IN MIXED SWELL PREVAIL ELSEWHERE.
FOR THE FORECAST, ANOTHER AREA OF LOW PRESSURE IS EXPECTED TO
DEVELOP WELL SOUTH OF THE SOUTHERN TIP OF THE BAJA CALIFORNIA
PENINSULA DURING THE MIDDLE PORTION OF THIS WEEK. SOME SLOW
DEVELOPMENT IS EXPECTED THEREAFTER, AND A TROPICAL DEPRESSION
COULD FORM BY THE END OF THE WEEK WHILE THE SYSTEM MOVES
GENERALLY WEST-NORTHWESTWARD. THIS SYSTEM HAS A MEDIUM CHANCE
FOR TROPICAL CYCLONE FORMATION THROUGH 7 DAYS.
GR
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