360
AXPZ20 KNHC 180248
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU DEC 18 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0230 UTC.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH
THE MONSOON TROUGH EXTENDS FROM 09N85W TO 09N95W. THE ITCZ
CONTINUES FROM 09N95W TO BEYOND 07N140W. SCATTERED MODERATE
CONVECTION IS NOTED FROM 06N TO 12N BETWEEN 92W AND 116W.
..OFFSHORE WATERS WITHIN 250 NM OF MEXICO
A 1025 MB HIGH CENTER IS ANALYZED JUST N OF THE AREA NEAR
33N130W WITH THE ASSOCIATED RIDGE EXTENDING TO NEAR THE
REVILLAGIGEDO ISLANDS. THE RELATED PRESSURE GRADIENT IS ALLOWING
FOR GENTLE TO MODERATE NORTHWEST TO NORTH WINDS AND SLIGHT TO
MODERATE SEAS OVER THE MEXICAN OFFSHORE WATERS INCLUDING THE GULF
OF CALIFORNIA. IN THE FAR OUTER BAJA CALIFORNIA NORTE WATERS AND
BEYOND, FRESH NW WINDS AND ROUGH SEAS ARE PRESENT DUE TO A TIGHT
PRESSURE GRADIENT MAINLY N OF THE AREA WITH A HIGH PRESSURE
INLAND OF THE SAN FRANCISCO BAY AREA AND TROUGHING JUST TO THE S
OVER THE CHANNEL ISLANDS.
FOR THE FORECAST, MODERATE TO FRESH WINDS WILL PULSE NEAR CABO
CORRIENTES THROUGH TONIGHT, THEN AGAIN THIS WEEKEND. SIMILAR
WINDS WILL BE WELL OFFSHORE BAJA CALIFORNIA NORTE THROUGH THE END
OF THE WEEK, ALONG WITH ROUGH SEAS DUE TO A TIGHT PRESSURE
GRADIENT MAINLY N OF THE THE AREA. FRESH TO STRONG GAP WINDS AND
ASSOCIATED ROUGH SEAS MAY DEVELOP IN THE GULF OF TEHUANTEPEC FRI
THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK AS THE
PRESSURE GRADIENT TIGHTENS IN THE AREA. MODERATE OR WEAKER WINDS
AND SLIGHT TO MODERATE SEAS ARE FORECAST ELSEWHERE FOR THE NEXT
SEVERAL DAYS.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
FRESH NE WINDS PREVAIL IN THE GULF OF PAPAGAYO EXTENDING DOWNWIND
TO NEAR 09N92.5W WITH AS HIGH PRESSURE OVER NORTHERN CENTRAL
AMERICA AND LOWER PRESSURES ALONG THE MONSOON TROUGH OVER
SOUTHERN COSTA RICA AND PANAMA. LIGHT TO GENTLE WINDS AND
MODERATE SEAS ARE ELSEWHERE N OF 06N. S OF 06N, GENTLE TO
MODERATE SOUTHERLY WINDS AND MODERATE SEAS PREVAIL PER EARLIER
ASCAT SCATTEROMETER DATA, EXCEPT SLIGHT SEAS NEARSHORE COLOMBIA,
EASTERN PANAMA, AND SOUTHERN COSTA RICA PER AN ALTIMETER PASS.
ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE
PRESENT OFFSHORE COLOMBIA NORTHWARD PER CONVENTIONAL SATELLITE
IMAGERY.
FOR THE FORECAST, HIGH PRESSURE OVER INTERIOR NORTHERN CENTRAL
AMERICA AND LOWER PRESSURES NEAR THE MONSOON TROUGH WILL SUPPORT
PULSING MODERATE TO FRESH EASTERLY TRADE WINDS AND MODERATE SEAS
ACROSS THE GULF OF PAPAGAYO THROUGH FRI WHILE EXTENDING WELL
DOWNWIND TO THE FAR OUTER OFFSHORE WATERS OF EL SALVADOR AND
GUATEMALA, THEN INCREASING TO FRESH TO STRONG IN THE GULF OF
PAPAGAYO FRI AFTERNOON THROUGH THE UPCOMING WEEKEND AND INTO
EARLY NEXT WEEK AS THE GRADIENT TIGHTENS. MODERATE TO FRESH
NORTHERLY WINDS WILL PULSE AT TIMES IN THE GULF OF PANAMA THROUGH
THE NEXT SEVERAL DAYS. GENTLE TO MODERATE WINDS AND SLIGHT TO
MODERATE SEAS WILL PREVAIL ELSEWHERE.
..REMAINDER OF THE AREA
A 1025 MB HIGH CENTER IS ANALYZED JUST N OF THE AREA NEAR
33N130W WITH THE ASSOCIATED RIDGE EXTENDING TO NEAR THE
REVILLAGIGEDO ISLANDS. THE PRESSURE GRADIENT BETWEEN THE HIGH AND
RELATIVELY LOWER PRESSURES NEAR THE ITCZ/MONSOON TROUGH IS
BRINGING MODERATE TO FRESH TRADE WINDS FROM 08N TO 22N AND W OF
120W WHERE SEAS ARE 6-9 FT PER MULTIPLE EARLIER ALTIMETER PASSES.
A TIGHT PRESSURE GRADIENT OVER SOUTHERN CALIFORNIA AND OFFSHORE
SUPPORTS FRESH TO STRONG WINDS AND LOCALLY ROUGH SEAS EXTENDING
OVER OUR WATERS N OF 2118W AND 126.5N. GENTLE TO MODERATE WINDS
AND MAINLY MODERATE SEAS PREVAIL ACROSS THE REMAINDER OF THE OPEN
WATERS, INCLUDING S OF THE MONSOON TROUGH AND ITCZ.
FOR THE FORECAST, HIGH PRESSURE WILL CONTINUE OVER THE NORTHERN
WATERS TONIGHT LEADING TO FRESH EASTERLY WINDS AND ROUGH SEAS
OVER MUCH OF THE TRADEWIND BELT WEST OF 125W. A TIGHT PRESSURE
GRADIENT WILL PERSIST OVER AND OFFSHORE SOUTHERN CALIFORNIA
LEADING TO FRESH TO LOCALLY STRONG WINDS AND ROUGH SEAS IN THE
N-CENTRAL WATERS THROUGH THE REMAINDER OF THE WORK WEEK. MARINE
CONDITIONS SHOULD IMPROVE OVERALL DURING THE UPCOMING WEEKEND AS
THE PRESSURE GRADIENT SLACKENS DUE TO A COLD FRONT APPROACHING
30N140W. THAT FRONT MAY MOVE SE INTO THE NW AND N-CENTRAL WATERS
EARLY NEXT WEEK WITH THE POTENTIAL FOR FRESH TO STRONG NE WINDS
AND ROUGH SEAS BEHIND IT.
ERA
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