000
AXPZ20 KNHC 271510
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1605 UTC WED NOV 27 2013

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 
1345 UTC.

...SPECIAL FEATURES...

A STORM WARNING IS IN EFFECT FOR THE GULF OF TEHUANTEPEC. THE 
0548 UTC OSCAT PASS SHOWED 40-45 KT WINDS IN THE GULF...WELL 
PRIOR TO THE TIME OF PEAK NOCTURNAL DRAINAGE FLOW OFF THE LAND. 
THE COLD AND DRY AIR MASS ENCOUNTERED THAT FUNNELED THROUGH 
CHIVELA PASS SEA SURFACE TEMPERATURES NEAR 29 DEGREES CELSIUS AS 
IT MOVED OVER THE GULF WATERS. THE STRONG CONTRAST BETWEEN AIR 
AND SEA SURFACE TEMPERATURES PROMOTED MIXING OF STRONG WINDS 
ALOFT DOWN TO THE SURFACE. STORM CONDITIONS ARE EXPECTED TO 
PERSIST UNTIL AROUND SUNSET TONIGHT WHEN THEY WILL DIMINISH BACK 
TO GALE FORCE. GALE FORCE WINDS ARE THEN EXPECTED TO REMAIN AT 
GALE FORCE UNTIL LATE SAT NIGHT/EARLY SUN. THE PROLONGED PERIOD 
OF SUCH WINDS WILL RESULT IN AN IMPRESSIVE PLUME OF NE SWELL 
WHICH WILL MANAGE TO PROPAGATE S TO THE EQUATOR AND W TO 110W BY 
SUNRISE FRI. SIGNIFICANT WAVE HEIGHTS IN THE GULF WILL BUILD TO 
AS HIGH AS 22 FT BY LATE THIS AFTERNOON.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 07N100W TO 
09N115W TO 08N122W. THE ITCZ AXIS EXTENDS FROM 08N122W TO 
10N130W TO 07N140W. SCATTERED MODERATE WITH ISOLATED STRONG 
CONVECTION LIES WITHIN 75 NM S OF THE AXIS BETWEEN 115W AND 
117W. SCATTERED MODERATE CONVECTION LIES WITHIN 120 NM N OF 
THE AXIS W OF 132W.

...DISCUSSION...

A STRONG COLD FRONT HAS MOVED THROUGH THE NW PORTION OF THE 
FORECAST AREA AND LIES FROM 30N131W TO 26N140W. FRESH TO STRONG 
NW WINDS AND 10-15 FT NW SWELLS LIE BEHIND THE FRONT...WITH 
FRESH TO STRONG SW WINDS AND 8-10 FT SEAS N OF 28N WITHIN 120 NM 
E OF THE FRONT. NW SWELL WILL BUILD TO 18 FEET TODAY. SEAS WILL 
BEGIN TO SUBSIDE AND THE FRONT WILL WEAKEN TOMORROW...WITH WINDS 
20 KT OR LESS NEAR THE FRONT BY SUNRISE FRI. SEAS OF 8 FT OR 
GREATER WILL CONTINUE TO PROPAGATE TO THE SE SPREADING OVER THE 
REGION W OF A LINE FROM 30N116W TO 17N120W TO 08N140W BY THIS 
TIME FRI.

A SURFACE TROUGH EMBEDDED IN THE ITCZ EXTENDS FROM 14N126W TO 
07N132W. AN ASCAT PASS FROM 0726 UTC SHOWED STRONG NE WINDS ON 
THE NW SIDE OF THE TROUGH. THE PRESSURE GRADIENT BETWEEN THE 
TROUGH AND THE SUBTROPICAL RIDGE TO ITS N WILL WEAKEN OVER THE 
NEXT TWO DAYS AS THE COLD FRONT AND ITS SUPPORTING AREA OF LOW 
PRESSURE ERODE THE RIDGE FROM THE N. NE SWELL WILL CONTINUE TO 
KEEP SEAS W OF THE TROUGH IN THE 8-10 FT RANGE INTO THU WITH 
THESE SEAS MERGING WITH THE NW SWELL ASSOCIATED WITH THE COLD 
FRONT TO THE N BY FRI. 

GAP WINDS...FRESH TO STRONG N-NE WINDS ARE EXPECTED TO SURGE 
THROUGH BOTH THE GULF OF FONSECA AND THE GULF OF PAPAGAYO 
OVERNIGHT TONIGHT. THE GULF OF FONSECA EVENT WILL BE 
BRIEF...ONLY PERSISTING THROUGH SUNRISE ON THU. THE NE FLOW WILL 
CONTINUE TO SURGE THROUGH THE GULF OF PAPAGAYO THROUGH SUNRISE 
ON SUN...PEAKING AT 30 KT EARLY FRI. NE SWELL FROM THIS EVENT 
WILL MIX WITH LONG PERIOD S SWELL AS WELL AS N-NW SWELL FROM 
TEHUANTEPEC...RESULTING IN COMBINED SEAS UP TO 11 FT. 
 
$$
SCHAUER