000
AXPZ20 KNHC 271524
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC MON OCT 27 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 1008 MB LOW IS CENTERED NEAR 09N96W AND IS ACCOMPANIED BY 
SCATTERED MODERATE AND ISOLATED STRONG CONVECTION WITHIN 180 NM 
OF THE CENTER.  AN OVERNIGHT SCATTEROMETER PASS INDICATED PEAK 
WINDS OF ABOUT 20 KT...PRIMARILY WITHIN THE SOUTHERN SEMICIRCLE. 
THE LOW REMAINS EMBEDDED ALONG THE MONSOON TROUGH CURRENTLY.  AN 
UPPER-LEVEL RIDGE IS NORTHEAST OF THE SURFACE LOW...INDUCING 
SOME SOUTHEASTERLY WINDS ALOFT AND SOME MODERATE VERTICAL SHEAR. 
GLOBAL MODELS DO SUGGEST DEVELOPMENT OF THE SYSTEM AS A TROPICAL 
CYCLONE WITH MOST DEVELOPMENT OCCURRING AFTER TWO TO THREE DAYS. 
THE LOW HAS A 40 PERCENT...MODERATE...CHANCE OF FORMATION WITHIN 
48 HOURS AND AN 80 PERCENT...HIGH...CHANCE OF FORMATION WITHIN 
FIVE DAYS. MOVEMENT OF THE SYSTEM SHOULD BE SLOWLY OFF TO THE 
WEST-NORTHWEST FOR THE NEXT COUPLE OF DAYS...REMAINING OFFSHORE 
FOR THE SHORT-TERM. AN EARLIER ALTIMETER DATA INDICATES SEAS ARE 
IN THE 8 TO 9 FT RANGE NEAR THE LOW...PRIMARILY DUE TO LONGER 
PERIOD SW SWELL.
                    
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
MONSOON TROUGH AXIS EXTENDS FROM 09N79W TO 1008 MB LOW PRES NEAR 
09N96W TO 1011 MB LOW PRES NEAR 08N114W TO 09N130W. ITCZ AXIS 
EXTENDS FROM 09N130W TO 08N138W. SCATTERED MODERATE ISOLATED 
STRONG CONVECTION EXISTS BETWEEN 93W AND 100W WITHIN 120 NM OF 
AXIS.  SCATTERED MODERATE CONVECTION EXISTS BETWEEN 105W AND 
115W WITHIN 60 NM OF AXIS.
 
...DISCUSSION...                                                

A MODERATE 1022 MB HIGH IS CENTERED JUST NORTH OF OUR AREA NEAR 
34N133W.  THE RESULTING PRESSURE GRADIENT ON THE EQUATORWARD 
SIDE OF THE HIGH IS PRODUCING STRONG BREEZE NE TRADEWINDS FROM 
15N TO 18N BETWEEN 132W AND 136W.  ELSEWHERE THE TRADES ARE 
MODERATE TO FRESH BREEZE CONDITIONS.  AN EARLIER COLD FRONT 
NORTH OF THE AREA HAD INDUCED A SIGNIFICANT NORTHWESTERLY SWELL 
EVENT.  SEAS 8 TO 11 FT COVER MUCH OF OUR AREA THIS 
MORNING...THOUGH THESE SHOULD GRADUALLY DIMINISH AND DROP BELOW 
8 FT IN ABOUT TWO DAYS.  THE NEXT LONG-PERIOD SWELL EVENT SHOULD 
REACH THE NORTHWESTERN PORTION OF OUR AREA ON FRIDAY.

GULF OF TEHUANTEPEC...A STRONG BREEZE GAP WIND EVENT IS ONGOING 
IN THE GULF OF TEHUANTEPEC.  AN EARLIER SCATTEROMETER PASS 
INDICATED WINDS OF UP TO 30 KT...THOUGH THESE HAVE LIKELY 
DIMINISHED TO 25 KT THIS MORNING.  AN EARLIER ALTIMETER PASS 
INDICATED 8 TO 10 FT WAVE HEIGHT...THOUGH THIS IS LIKELY DOWN TO 
ABOUT 8 FT THIS MORNING.  FORCING OF THE EVENT IS LIKELY TO 
FURTHER DIMINISH AND DROP TO 20 KT BY THIS EVENING.  HOWEVER 
...A STRONG COLD FRONT ANTICIPATED TO PUSH ACROSS THE GULF OF 
MEXICO LATE IN THE WEEK SHOULD KICK OFF A NEW AND VIGOROUS 
TEHUANTEPECER ON FRIDAY.  THIS EVENT MAY REACH GALE FORCE ON 
SATURDAY AND SUNDAY.  

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