000
AXPZ20 KNHC 112155
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI OCT 11 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...SPECIAL FEATURES...
LOW PRES 1009 MB EMBEDDED IN MONSOON TROUGH AT 14N106W HAS 
MODERATE TO FRESH WINDS ON ITS WESTERN SEMICIRCLE.  SYSTEM IS A
TOSS UP BETWEEN A FAVORABLE LOWER LEVEL CONDITIONS...WARM SST 
AND PLENTY OF TROPICAL MOISTURE WITH GOOD MECHANICAL UPLIFT...
AND UPPER LEVEL ANTICYCLONE WHICH PUMPS AN INCREASING SOUTHEAST
SHEAR OVER IT.  CONVECTION REMAINS DISORGANIZED...BUT ABUNDANT. 
MODEL GUIDANCE HAVE DIVERGENT SOLUTIONS WITH STATISTICAL ONES 
BUILDING A SHORT-LIVED TROPICAL STORM...BUT DYNAMICAL MODELS 
HOLDING A STEP SHY OF IT.  THERE IS A MEDIUM CHANCE OF TROPICAL
CYCLONE DEVELOPMENT DURING THE NEXT 48 HOURS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
MONSOON TROUGH EXTENDS FROM 10N85W TO 09N93W TO 1009 MB LOW PRES
AT 14N106W TO 14N114W TO 11N124W THEN RESUMES FROM REMNANT 1010
MB LOW PRES NARDA AT 16N131W TO 11N135W TO BEYOND 09N140W.
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WITHIN 240 NM
OF AXIS FROM 90W TO 120W AND 240 NM S OF AXIS E OF 85W.

...DISCUSSION...
UPPER LEVEL TROUGH CUTS DEEP INTO BASIN FROM 32N120W TO 15N128W
WITH VERY DRY AND STABLE SUBSIDING AIR MASS W OF AXIS.  STUBBORN
MID-UPPER LEVEL DOWNSTREAM RIDGE OVER CENTRAL MEXICO BLOCKS ANY
FURTHER EASTWARD MOVEMENT OF TROUGH AND IS IN TURN SQUEEZED ON
ITS WESTERN PERIPHERY INCREASING SOUTHERLY WINDS INCLUDING S-SE 
WINDS OVER SURFACE LOW PRES 1009 MB AT 14N106W.  THIS INCREASED 
SHEAR OVER LOW PRES HINDERS...OR MAY EVEN PREVENT ITS POSSIBLE
DEVELOPMENT INTO A TROPICAL CYCLONE.  ON THE OTHER HAND...RIDGE
ALSO ALLOWS ABUNDANT TROPICAL MOISTURE TO MOVE INTO E PAC ALONG
MONSOON TROUGH E OF 120W. 

UPPER LEVEL SHORTWAVE ROTATING AROUND TROUGH AT 32N INCREASES
NW WINDS N OF 32N AND ALLOWS MODERATE N-NW SWELL TRAIN TO MOVE S
AS FAR AS TO REACH 14N W OF 130W DURING THE WEEKEND.  

...ELSEWHERE AT THE LOWER LEVELS...
FARTHER W...REMNANT LOW PRES 1010 MB OF NARDA PERSISTS AT 16N131W
WITH A DEFINITELY WELL DEFINED CYCLONIC CIRCULATION...BUT TOTAL 
ABSENCE OF CONVECTION WITHIN 200 NM OF ITS CENTER.  STILL...THE
SYSTEM IS ABLE TO TIGHTEN PRES GRADIENT ENOUGH TO PROMPT FRESH
NE BREEZE ON ITS NW QUADRANT THROUGH FORECAST PERIOD.  
 
$$
WALLY BARNES