000
AXPZ20 KNHC 281510
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC TUE OCT 28 2014

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.                       

...SPECIAL FEATURES...                                           
A 1007 MB LOW IS CENTERED NEAR 11N97W AND IS ACCOMPANIED BY 
SCATTERED MODERATE CONVECTION WITHIN 180 NM OF THE CENTER... 
MAINLY WITHIN THE EASTERN SEMICIRCLE.  THE LOW REMAINS EMBEDDED 
ALONG THE MONSOON TROUGH CURRENTLY IN AN AREA OF HIGH LOW-LEVEL 
MOISTURE CONTENT. AN UPPER-LEVEL RIDGE IS JUST NORTHEAST OF THE 
SURFACE LOW...INDUCING WEAK SOUTHEASTERLY WINDS ALOFT AND LOW 
VERTICAL SHEAR. GLOBAL MODELS DO SUGGEST DEVELOPMENT OF THE 
SYSTEM AS A TROPICAL CYCLONE WITH MOST OF THE SPINUP OCCURRING 
AFTER A DAY OR TWO. THE LOW HAS NEAR 100 PERCENT...HIGH... 
CHANCE OF FORMATION WITHIN 48 HOURS. MOVEMENT OF THE SYSTEM 
SHOULD BE SLOWLY OFF TO THE WEST-NORTHWEST FOR THE NEXT COUPLE 
OF DAYS...REMAINING OFFSHORE FOR THE SHORT-TERM. WINDS ARE 
CAPPED AT 30 KT AND SEAS ARE CAPPED AT 15 FT IN THE GRIDDED AND 
HIGH SEAS FORECAST.  HOWEVER...ONCE TROPICAL CYCLONE ADVISORIES 
COMMENCE...BOTH WINDS AND SEAS WILL HAVE TO BE CONSIDERABLY 
BUMPED UP.
                    
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
THE MONSOON TROUGH AXIS EXTENDS FROM 10N86W TO A 1007 MB LOW 
PRESSURE NEAR 11N97W TO 10N109W.  ITCZ AXIS EXTENDS FROM 10N109W 
TO 1011 MB LOW PRESSURE NEAR 11N117W TO 09N140W. SCATTERED 
MODERATE CONVECTION EXISTS WITHIN 60 NM OF AXIS BETWEEN 93W AND 
98W...AND WITHIN 180 NM OF AXIS BETWEEN 112W AND 123W.  
SCATTERED MODERATE ISOLATED STRONG CONVECTIONS EXISTS WITHIN 240 
NM OF AXIS W OF 128W.
 
...DISCUSSION...                                                
A MODERATE 1022 MB HIGH IS CENTERED JUST NORTH OF OUR AREA NEAR 
32N131W.  THE RESULTING PRESSURE GRADIENT ON THE EQUATORWARD 
SIDE OF THE HIGH IS RELATIVELY WEAK IN PRODUCING NO STRONG 
BREEZE OR STRONGER WINDS. AN EARLIER COLD FRONT NORTH OF THE 
AREA HAD INDUCED A SIGNIFICANT NORTHWESTERLY SWELL EVENT.  
HOWEVER...NOW THE SEAS HAVE DROPPED TO 8 TO 9 FT OVER JUST WEST 
OF BAJA CALIFORNIA AND THE WEST CENTRAL PORTION OF OUR AREA.  
THESE SHOULD FURTHER DIMINISH AND DROP BELOW 8 FT IN LESS THAN A 
DAY.  

A COLD FRONT WILL REACH OUR NORTHWESTERN CORNER THURSDAY 
MORNING.  THOUGH THE WINDS WILL REMAIN AT FRESH BREEZE OR WEAKER 
CONDITIONS AS THE FRONT COMES THROUGH...A MODERATE 12-14 SECOND 
LONG-PERIOD SWELL EVENT OF 8-12 FT WAVE HEIGHTS SHOULD BEGIN 
PUSHING THROUGH THE NORTHWESTERN PORTION OF OUR AREA ON FRIDAY.

GULF OF TEHUANTEPEC...A COLD FRONT ANTICIPATED TO MOVE ACROSS 
THE GULF OF MEXICO LATE IN THE WEEK SHOULD KICK OFF A NEW AND 
VIGOROUS TEHUANTEPECER ON FRIDAY.  WHILE THE BUILDING HIGH 
PRESSURE IN THE SOUTHWESTERN GULF OF MEXICO MAY CAUSE SOME 
SPORADIC WEAK GAP WINDS IN THE GULF OF TEHUANTEPEC ON THURSDAY
...A STRONGER AND MORE CONTINUOUS EVENT IS EXPECTED BEGINNING ON 
LATE FRIDAY THROUGH SUNDAY. THE GLOBAL MODELS CURRENTLY ARE 
CALLING FOR EITHER NEAR GALE OR GALE CONDITIONS AT ITS PEAK.  
THE EVENT SHOULD FADE BY MONDAY. 

FOR THE GRIDDED FORECAST...A BLEND OF THE GFS AND ECMWF MODELS 
ALONG WITH THE PREVIOUS PREDICTION WERE USED FOR THE WINDS AND 
THE GFS-BASED WAVEWATCH MODEL ALONG WITH THE PREVIOUS PREDICTION 
WERE USED FOR THE WAVES.

$$ 
LANDSEA