280
AXPZ20 KNHC 190920
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT SEP 19 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0920 UTC.
..SPECIAL FEATURES
WESTERN EAST PACIFIC: LOW PRESSURE, INVEST EP98, IS CENTERED NEAR
12N119W WITH A PRESSURE OF 1009 MB. THIS FEATURE IS PART OF A
RATHER BROAD AREA OF CYCLONIC CIRCULATION. SATELLITE IMAGERY
EXHIBITS SCATTERED MODERATE TO ISOLATED STRONG CONVECTION FROM
04N TO 17N BETWEEN 118W AND 135W. ENVIRONMENTAL CONDITIONS ARE
CONDUCIVE FOR DEVELOPMENT, AND A TROPICAL DEPRESSION IS EXPECTED
TO FORM THIS WEEKEND AS IT MOVES WESTWARD TO WEST-NORTHWESTWARD
AT 10 TO 15 KT ACROSS THE WESTERN EAST PACIFIC. THE LOW HAS A
HIGH CHANCE OF TROPICAL CYCLONE FORMATION THROUGH THE NEXT 48
HOURS AND THE NEXT 7 DAYS.
SOUTH OF SOUTHWESTERN MEXICO: A TROPICAL WAVE, INVEST EP99, HAS ITS
AXIS EXTENDING FROM NEAR 18N108W TO 04N107W, WITH LOW PRESSURE
OF 1009 MB, NEAR 09N106W. THIS FEATURE IS PART OF A BROAD AREA
LOW PRESSURE THAT IS LOCATED ABOUT 700 NAUTICAL MILES SOUTH-
SOUTHWEST OF THE SOUTHWESTERN COAST OF MEXICO. SATELLITE IMAGERY
DEPICTS SCATTERED MODERATE ISOLATED STRONG CONVECTION FROM 05N
TO 15N BETWEEN 99W AND 112W. ENVIRONMENTAL CONDITIONS ARE
CONDUCIVE FOR DEVELOPMENT, AND A TROPICAL DEPRESSION IS EXPECTED
TO FORM LATE THIS WEEKEND OR EARLY NEXT WEEK WHILE IT MOVES
GENERALLY NORTHWARD OFF THE COAST OF SOUTHWESTERN MEXICO. THIS
SYSTEM HAS A HIGH CHANCE OF TROPICAL CYCLONE FORMATION THROUGH
THE NEXT 48 HOURS AND A HIGH CHANCE OF DEVELOPMENT WITHIN THE
NEXT 7 DAYS.
PLEASE REFER TO THE LATEST NHC TROPICAL WEATHER OUTLOOK AT
WEBSITE: WWW.HURRICANES.GOV FOR MORE DETAILS ON THESE INVESTS.
..TROPICAL WAVES
A TROPICAL WAVE IN THE WESTERN CARIBBEAN SEA WITH AXIS NEAR 82W
EXTENDS SOUTHWARD ACROSS W PANAMA AND ITS OFFSHORE WATERS. IT IS
MOVING WESTWARD NEAR 15 KT. NUMEROUS MODERATE TO ISOLATED STRONG
CONVECTION IS FROM 05N TO 10N BETWEEN 80W AND 89W.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 09N106W TO
12N120W TO 15N136W. SCATTERED MODERATE TO ISOLATED STRONG
CONVECTION IS FROM 03N TO 16N BETWEEN 90W AND 100W, AND FROM 07N
TO 20N BETWEEN 130W AND 138W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
THE PRESSURE GRADIENT BETWEEN A RIDGE OVER EASTERN MEXICO AND
THE EASTERN EXTENSION OF THE PACIFIC MONSOON IS SUPPORTING FRESH
N GAP WINDS ACROSS THE GULF OF TEHUANTEPEC. SEAS WITH THESE WINDS
ARE 5 TO 6 FT. SCATTERED SHOWERS ARE OVER THE OFFSHORE WATERS
BETWEEN OAXACA AND GUERRERO DUE TO INVEST EP99 AND THE MONSOON
SOUTH OF THE REGION. THE GRADIENT RELATED TO HIGH PRESSURE WEST
OF THE BAJA CALIFORNIA OFFSHORES AND LOW PRESSURE ALONG WESTERN
MEXICO IS SUPPORTING FRESH TO LOCALLY STRONG NW WINDS N OF CABO
SAN LAZARO. MODERATE OR WEAKER WINDS ARE ELSEWHERE ALONG WITH
MODERATE SEAS, EXCEPT FOR SLIGHT SEAS IN THE GULF OF CALIFORNIA.
FOR THE FORECAST, WINDS WILL PULSE TO FRESH TO STRONG SPEEDS IN
THE GULF OF TEHUANTEPEC BECOMING MODERATE N TO NE WINDS THIS
AFTERNOON. FRESH TO STRONG NW WINDS OFFSHORE BAJA CALIFORNIA WILL
DIMINISH THIS AFTERNOON. NORTHWEST WINDS OVER THESE WATERS ARE
EXPECTED TO BRIEFLY REACH FRESH SPEEDS AGAIN MON NIGHT INTO TUE.
OTHERWISE, THE ENVIRONMENTAL CONDITIONS OF INVEST EP99, NEAR
09N106W, ARE CONDUCIVE FOR DEVELOPMENT AND A TROPICAL DEPRESSION
IS EXPECTED TO FORM LATE THIS WEEKEND OR EARLY NEXT WEEK WHILE
IT MOVES GENERALLY NORTHWARD OFF THE COAST OF SOUTHWESTERN
MEXICO. REGARDLESS OF DEVELOPMENT, THIS SYSTEM IS FORECAST TO
BRING FRESH TO NEAR GALE-FORCE WINDS AND MODERATE TO ROUGH SEAS
TO THE MICHOACAN AND JALISCO OFFSHORES TONIGHT INTO WED NIGHT.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
MODERATE NE TO E WINDS ARE ACROSS THE GULF OF PAPAGAYO EXTENDING
DOWNSTREAM TO NEAR 88W. MODERATE OR WEAKER WINDS PREVAIL
ELSEWHERE, EXCEPT FOR STRONG WINDS LIKELY ONGOING ACROSS THE W
PANAMA AND COSTA RICA OFFSHORES DUE TO STRONG CONVECTIVE ACTIVITY
ASSOCIATED WITH A TROPICAL WAVE. SEAS OVER THE OFFSHORE WATERS
ARE SLIGHT TO MODERATE IN LONG-PERIOD SOUTHWEST SWELL.
FOR THE FORECAST, MODERATE TO FRESH NE TO E WINDS WILL PULSE IN
PAPAGAYO THROUGH EARLY SUN. MODERATE WINDS AND SEAS WILL PREVAIL
ELSEWHERE.
..REMAINDER OF THE AREA
THE REMNANT 1008 MB LOW OF FORMER TROPICAL DEPRESSION FIFTEEN-E
IS LOCATED NEAR 16N138W. A TIGHT GRADIENT BETWEEN THE LOW AND
HIGH PRESSURE OF 1026 MB TO ITS NORTH IS BRINGING FRESH TO
STRONG NORTHEAST TO EAST WINDS OVER THE WATERS FROM 16N TO 26N
WEST OF 121W. SEAS ARE 6 TO 9 FT WITHIN THIS AREA OF WINDS.
SATELLITE IMAGERY SHOWS SCATTERED MODERATE ISOLATED STRONG
CONVECTION FROM 07N TO 20N BETWEEN 130W AND 138W. ELSEWHERE,
WINDS ARE MODERATE OR WEAKER FOR THE MOST PART AND SEAS ARE OF
MODERATE STATE, EXCEPT FOR MODERATE TO FRESH WINDS IN THE
VICINITY OF INVEST EP99.
FOR THE FORECAST, SEE THE SPECIAL FEATURES SECTION. OTHERWISE,
ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR SOME DEVELOPMENT
OF FORMER TD 15-E NEXT WEEK AS IT MOVES WESTWARD TO WEST-
SOUTHWESTWARD, AND A TROPICAL DEPRESSION COULD FORM WELL TO THE
SOUTH OR SOUTHEAST OF THE HAWAIIAN ISLANDS BY THE MIDDLE TO
LATTER PART OF NEXT WEEK.
RAMOS
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