000
AXPZ20 KNHC 021607
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED OCT 02 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 
1545 UTC.

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

THE MONSOON TROUGH AXIS EXTENDS FROM NW COLOMBIA TO ACROSS THE 
GULF OF PANAMA NW TO 09N84W TO 13N100W TO AN EMBEDDED 1009 MB 
LOW PRES NEAR 15N107W...THEN SW TO 13N115W TO 12N125W TO 
10N130W...WHERE LATEST SCATTEROMETER DATA INDICATES A TRANSITION 
TO AN ITCZ AXIS WHICH CONTINUES TO BEYOND 09N140W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF THE 
ITCZ W OF 133W. 

...DISCUSSION...

AN UPPER LEVEL TROUGH IS PRESENT OVER THE FAR NW PORTION OF THE 
AREA WITH ITS AXIS EXTENDING FROM 32N129W SW TO A SMALL CYCLONIC 
CIRCULATION DIVING SSE AT 27N140W. AN UPPER LEVEL ANTICYCLONE 
IS OVER THE FAR EASTER PART OF THE AREA AT 18N105W WITH A RIDGE  
EXTENDING NNW TO ACROSS THE GULF OF CALIFORNIA...AND TO FAR 
SOUTHERN CALIFORNIA. ANOTHER RIDGE EXTENDS SW FROM THE 
ANTICYCLONE TO NEAR 20N128. THESE UPPER FEATURES ARE DRYING OUT 
THE MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE NW AND N OF A LINE 
FROM CABO CORRIENTES MEXICO TO 17N123W TO 12N130W TO 11N140W. 
 
UPPER LEVEL CYCLONIC FLOW IS NOTED S OF 11N W OF 110W WITH A 
RELATED CYCLONIC CIRCULATION MOVING SE NEAR 02N119W. AN AREA OF 
UPPER DIFFLUENCE N OF THE CYCLONIC FLOW AND SW OF THE UPPER 
RIDGE PREVIOUSLY DESCRIBED IS OVER THE MONSOON TROUGH AND ITCZ 
CONVECTION DESCRIBED ABOVE. AN INVERTED MID UPPER LEVEL TROUGH 
IS BETWEEN THE ANTICYCLONE AT 18N105W AND THE RIDGE TO ITS NW 
ROUGHLY EXTENDING FROM 23N115W TO 17N121W TO A SMALL CYCLONIC 
CIRCULATION AT 13N127W. SMALL CLUSTERS OF SCATTERED MODERATE 
CONVECTION ARE SEEN WITHIN ABOUT 210 NM SE OF THE TROUGH.

A 1009 MB LOW IS CENTERED NEAR 15N108W MOVING SLOWLY WNW. THIS 
LOW IS UNDER THE SOUTHERN PERIPHERY OF THE UPPER LEVEL 
ANTICYCLONE AT 18N105W....AND TO THE W OF UPPER LEVEL 
ANTICYCLONIC RIDGING THAT EXTENDS FROM THE NW CARIBBEAN SEA SW 
TO NEAR 13N100W. LATEST SATELLITE IMAGERY SHOW THAT THE CYCLONIC 
CIRCULATION WITH THIS LOW HAS BECOME MORE EVIDENT DURING THE 
LATE NIGHT AND EARLY MORNING HOURS. IN ADDITION... SCATTERED 
MODERATE CONVECTION IS WITHIN 150 NM OF THE LOW IN THE NE AND E 
QUADRANTS. GLOBAL MODELS FORECAST THIS LOW TO MOVE IN A GENERAL 
MORE WESTWARD DIRECTION OVER THE NEXT 24 TO 48 HOURS WITH NO 
SIGNIFICANT STRENGTHENING EXPECTED. 

ELSEWHERE AT THE SURFACE...A BROAD RIDGE ASSOCIATED WITH A 1028 
MB HIGH N OF THE AREA AT 38N140W COVERS THE DISCUSSION AREA N OF 
16N W OF 121W. LONG PERIOD NW SWELLS HAVE PROPAGATED S INTO THE 
NW PORTION OF THE DISCUSSION AREA WITH COMBINED SEA HEIGHTS OF 9-
11 FT TO THE N OF 26N BETWEEN 118W-126W...AND SEAS 8-10 FT 
ELSEWHERE N OF A LINE FROM 24N114W TO 09N120W TO 08N130W TO 
13N140W. THESE SWELLS WILL GRADUALLY SUBSIDE FROM NW TO SE 
BEGINNING ON THU WITH SEAS BELOW 8 FT ACROSS THE DISCUSSION AREA 
THROUGH SAT.  
 
$$
AGUIRRE