000
AXPZ20 KNHC 301605
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN DEC 30 2012

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 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.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM 08N77W TO 08N101W. THE ITCZ 
EXTENDS FROM 08N101W TO 09N121W TO 06N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION FROM 05N TO 07N E OF 90W. SCATTERED 
MODERATE TO STRONG CONVECTION FROM 11N TO 15N BETWEEN 11W AND 
120W. 

...DISCUSSION...

A SURFACE RIDGE EXTENDS SE ACROSS THE AREA FROM 32N140W TO 
22N109W. A COLD FRONT IS WEAKENING AS IT MOVES ACROSS THE 
NORTHERN BAJA PENINSULA. EXPECT THE FRONT TO CONTINUE TO WEAKEN 
AS IT MOVES ACROSS THE GULF OF CALIFORNIA TONIGHT. ANTICYCLONIC 
10-15 KT WINDS ARE OBSERVED ACROSS THE SUB-TROPICS...EXCEPT FOR 
A SMALL AREA OF NW 15-20 KT WINDS IN THE WAKE OF THE FRONT NEAR 
29N124W. SEAS ARE 7-12 FT IN MIXING N...NE...AND NW SWELL. THE 
NE TRADES S OF THE SURFACE RIDGE FROM 08-22N BETWEEN 127-140W 
CONTINUE AT 20-25 KT WITH SEAS 9-12 FT IN MIXED NE AND NW SWELL. 
ELSEWHERE W OF LINE FROM 26N115W TO 15N115W TO 07N140W SURFACE 
WINDS ARE N TO NE AT 10-20 KT WITH SEAS 8-10 FT PRIMARILY DUE TO 
MIXING LONG PERIOD NE AND NW SWELL.

A SURFACE HIGH WILL SHIFT S INTO THE AREA NEAR 30N130W LATE MON 
MAINTAINING THE NE TRADES IN THE AREA FROM 08-20N W OF 130W WITH 
SEAS 9-12 FT IN MIXED NE AND NW SWELL. LARGE LONG PERIOD NW 
SWELL WILL PROPAGATE INTO THE FAR NW PACIFIC WATERS TONIGHT 
DRIVING SEAS UP TO 13 FT. THESE NW SWELLS WILL CONTINUE EASTWARD 
BUT GRADUALLY SUBSIDE WITH SEAS OF 7-10 FT REACHING THE NORTHERN 
BAJA PENINSULA LATE TUE NIGHT...AND REACHING THE SOUTHERN BAJA 
PENINSULA LATE WED NIGHT. A COLD FRONT WILL ENTER THE WATERS 
NEAR 30N140W TUE NIGHT ACCOMPANIED BY A 20-25 KT SW-NW WIND 
SHIFT WITH SOUTHERLY GALE WINDS PRECEDING THE FRONT OVER THE 
WATERS N OF 31N.
 
GULF OF TEHUANTEPEC...THE WESTERN PORTION OF A SWATH OF RECENT 
HIGH RESOLUTION ASCAT WINDS DETECT N-NW 35 KT WINDS OVER THE 
EASTERN WATERS OF THE GULF OF TEHUANTEPEC. EXPECT STRONG N FLOW 
W OF RECENT ASCAT SWATH...THUS GALE FORCE WARNING IS IN EFFECT 
CONTINUING THROUGH SUNRISE MON...WITH THE NORTHERLY WINDS 
DIMINISHING BELOW 20 KT LATE MON. 

GULF OF PAPAGAYO...NE-E 15-25 KT SURGES ARE EXPECTED TO CONTINUE 
AND GRADUALLY SPREAD AS FAR W AS 94W BY TONIGHT WHERE THE 
ASSOCIATED NE SWELLS WILL THEN MIX WITH SW CROSS EQUATORIAL 
SWELL AS WELL AS N SWELL PROPAGATING S FROM THE STRONG 
TEHUANTEPEC EVENT.

GULF OF CALIFORNIA...LIGHT AND VARIABLE WINDS INDICATED EXCEPT A 
15-20 KT SW-W-NW WIND SHIFT IS EXPECTED OVER THE NORTHERN WATERS 
AS THE WEAKENING COLD FRONT PASSES TODAY-TONIGHT. NW WINDS AT 
10-15 KT EXPECTED MOST WATERS BY MON NIGHT AND INCREASING TO 
20-25 KT ACROSS THE GULF WATERS N OF 25N LATE TUE.    

$$
MUNDELL