000
AXPZ20 KNHC 250339
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN NOV 25 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

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

MONSOON TROUGH AXIS FROM 07N78W TO 08N82W TO 07N95W. ITCZ FROM 
08N100W TO 08N140W. NO SIGNIFICANT CONVECTION NOTED.
 
...DISCUSSION...

GULF OF TEHUANTEPEC...NORTHERLY GALE WINDS ARE CONTINUING 
DOWNWIND OF THE GULF OF TEHUANTEPEC. PEAKS WINDS AT SALINA CRUZ 
ON THE COAST OF THE GULF OF TEHUANTEPEC WERE APPROACHING GALE 
FORCE EARLIER. SCATTEROMETER DATA FROM 19 UTC INDICATED WINDS TO 
GALE FORCE. THE PRESSURE GRADIENT OVER THE AREA IS EXPECTED TO 
GRADUALLY WEAKEN OVER THE NEXT TWO DAYS AS THE HIGH PRES OVER 
THE BAY OF CAMPECHE DIMINISHES AND A SURFACE TROUGH S OF THE 
GULF OF TEHUANTEPEC MOVES WESTWARD. EXPECT THE WINDS TO DIMINISH 
BELOW GALE FORCE BY SUN AFTERNOON. ANOTHER COLD FRONT WILL PUSH 
INTO THE GULF OF MEXICO ON TUE...ALLOWING ANOTHER SURGE TO GALE 
FORCE AGAIN ON TUE NIGHT. 

GULF OF PAPAGAYO...LINGERING RIDGING FROM THE YUCATAN PENINSULA 
S TO NORTHERN NICARAGUA WILL KEEP THE PRESSURE GRADIENT TIGHT 
ENOUGH TO SUPPORT FRESH TO STRONG NE WINDS IN THE GULF OF 
PAPAGAYO THROUGH MON. SCATTEROMETER DATA INDICATED THE PLUME OF 
20 TO 25 KT REACHING AS FAR DOWNSTREAM AS 12N91W. THESE 
CONDITIONS WILL CONTINUE WITH LITTLE CHANGE THROUGH SUN AND 
BEGIN TO SHRINK IN AREA BY MON AS THE HIGH PRESSURE OVER CENTRAL 
AMERICA WEAKENS.

THE COMBINED FLOW FROM TEHUANTEPEC AND PAPAGAYO GAP WIND EVENTS 
ARE SUPPORTING THE DEVELOPMENT OF TROUGHING ALONG 98W FROM 04N 
TO 11N. THIS FEATURE IS EXPECTED TO STRENGTHEN AS IT PROGRESSES 
WESTWARD ALONG THE ITCZ TO 101W SUN MORNING AND NEAR 105W MON 
MORNING...ENHANCING THE FRESH TO STRONG TEHUANTEPEC FLOW...AND 
MIXING WITH EASTERLY SWELL GENERATED DOWNSTREAM FROM THE 
PAPAGAYO AREA.

W OF 110W...A 1024 MB HIGH PRES AREA REMAINS STATIONARY NEAR 
35N132W...WITH SURFACE RIDGE EXTENDING TO 20N113W. A PAIR OF 
ALTIMETER PASSES FROM EARLIER THIS MORNING ADDED CONFIDENCE TO 
WAVE MODEL CONSENSUS SHOWING SEAS OF 8 TO 11 FT IN MIXED FRESH 
NE AND LONGER PERIOD NW SWELL...IN AN AREA OF FRESH TRADES FROM 
ROUGHLY 06N TO 22N W OF 115W. WAVE MODELS ARE ALSO IN BETTER 
AGREEMENT SHOWING SEAS N OF 22N HAVE SUBSIDED BELOW 8 FT. 

LOOKING AHEAD...OPERATIONAL AND ENSEMBLE MODEL GUIDANCE 
CONTINUES BE IN DECENT AGREEMENT SHOWING A A COLD FRONT 
APPROACHING THE FAR NW PORTION OF THE DISCUSSION AREA LATE 
MON...REACHING FROM 32N135W TO 24N140W BY EARLY TUE. THIS WILL 
INCREASE THE SOUTHERLY FLOW TO 20-25 KT ACROSS THE WATERS N OF 
24N W OF 135W. LONG PERIOD NW SWELL OF 10 TO 15 FT WILL FOLLOW 
THE FRONT. THE WINDS SUBSIDE THROUGH MID WEEK AS THE MAIN 
SUPPORTING ENERGY ALOFT LIFTS NE. WW3 GUIDANCE SHOWS THE LEADING 
EDGE OF NW SWELL WITH SEAS 8 FT OR GREATER TO PUSH THROUGH THE 
AREA N OF 10N AND W OF 110W THROUGH LATE WEEK...REACHING THE 
NORTHERN COAST OF BAJA BY EARLY FRI. ECWAVE GUIDANCE IS MUCH 
SLOWER AND LIMITS THE 8 FT OR GREATER NW SWELL TO AN AREA N OF 
15N W OF 120W BY LATE THU...THEN DECAYING AFTERWARD. GIVEN THE 
LONGER FETCH AND DURATION OF THE NEXT SWELL EVENT...THE FORECAST 
FAVORS THE MORE AGGRESSIVE WW3 GUIDANCE. 

$$
CHRISTENSEN