000
AXPZ20 KNHC 150907
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI NOV 15 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...SPECIAL FEATURE...                                          
GALE FORCE WINDS CONTINUE ACROSS THE GULF OF TEHUANTEPEC BUT ARE 
DECREASING IN AREAL EXTENT. WINDS OVER THE GULF OF MEXICO WILL 
VEER TODAY. THIS WILL DECREASE WINDS FUNNELING THROUGH THE 
CHIVELA PASS INTO THE GULF OF TEHUANTEPEC. AS A RESULT...WINDS 
WILL DIMINISH BELOW GALE FORCE OVER THE GULF OF TEHUANTEPEC 
EARLY THIS MORNING THEN RAPIDLY DIMINISH BELOW 25 KT BY THIS 
EVENING. NE SWELLS WITH COMBINED SEAS OF 8 FT AND ABOVE 
GENERATED FROM THIS GAP WIND EVENT ARE CURRENTLY REACHING AS FAR 
WEST AS 110W...WITH MAX SEAS IN THE 14 FT RANGE NEAR THE GULF OF 
TEHUANTEPEC. WITH WINDS RAPIDLY DIMINISHING...SEAS WILL SUBSIDE 
RAPIDLY TODAY...AND ARE EXPECTED TO SUBSIDE BELOW 8 FT BY THIS 
EVENING.

LOW PRES 1007 MB WAS CENTERED NEAR 13.5N 109.0W. MODELS AGREE ON 
THE TRACK OF THE LOW...BUT DIFFER WIDELY ON ITS INTENSITY. THE 
ECMWF AND UKMET DEPICT A MUCH BROADER AND WEAKER CIRCULATION 
WHILE THE GFS IS PRODUCING A SIGNIFICANTLY STRONGER CIRCULATION. 
THERE ARE COMPETING INFLUENCES ON THE LOW WITH REGARDS TO 
TROPICAL CYCLOGENESIS. STRONG SW SHEAR IS AFFECTING THE LOW 
WHICH IS A NEGATIVE INFLUENCE FOR TROPICAL CYCLOGENESIS...BUT 
THE LOW IS MOVING OVER WATERS WITH WARM OCEANIC HEAT CONTENT AND 
IN AN ENVIRONMENT WITH ABUNDANT TROPICAL MOISTURE. THE CURRENT 
NHC FORECAST GIVES THE SYSTEM A MEDIUM CHANCE TO DEVELOP INTO A 
TROPICAL CYCLONE WITHIN THE NEXT 48 HOURS.
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
THE MONSOON TROUGH EXTENDS FROM 10N86W TO 08.5N93W TO LOW PRES 
NEAR 13N109W TO 08N130W WHERE LOW LEVEL WINDS SUGGEST A 
TRANSITION TO ITCZ WHICH EXTENDS TO BEYOND 07N140W. SCATTERED 
MODERATE CONVECTION WAS NOTED WITHIN 90 NM N OF TROUGH BETWEEN 
93W AND 98W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS 
NOTED WITHIN 150 NM N OF TROUGH BETWEEN 104W AND 107W. SCATTERED 
MODERATE CONVECTION WAS NOTED ELSEWHERE WITHIN 300 NM N OF 
TROUGH BETWEEN 102W AND 110W. 
 
...DISCUSSION... 
STRONG HIGH PRESSURE OF 1033 MB IS CENTERED NW OF THE AREA NEAR 
42N145W WITH ASSOCIATED RIDGE EXTENDING SE TO NEAR 22N118W. THE 
PRESSURE GRADIENT BETWEEN THE AREA OF HIGH PRESSURE AND LOWER 
PRESSURE WITHIN THE MONSOON TROUGH AND IN THE VICINITY OF THE 
ITCZ IS MAINTAINING FRESH TRADES OVER THE WESTERN PART OF THE 
AREA N OF THE ITCZ/MONSOON TROUGH AND W OF 130W. NW SWELLS ARE 
MOVING THROUGH THE AREA WITH SEAS 8 FT OR ABOVE COVERING THE 
AREA W OF A LINE FROM 30N120W TO 16N130W TO 08N131W...EXCEPT N 
OF 28N W OF 133W. THE HIGH PRESSURE CENTER WILL WEAKEN OVER THE 
NEXT COUPLE OF DAYS. THIS WILL LOOSEN THE PRESSURE GRADIENT AND 
DECREASE THE RESULTANT WINDS AND SEAS OVER THE FORECAST AREA. BY 
EARLY SUN MORNING...TRADES ARE EXPECTED TO DIMINISH TO 20 KT OR 
LESS WITH SEAS SUBSIDING TO BELOW 8 FT OVER THE WESTERN PART OF 
THE FORECAST AREA. 

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AL