000
AXPZ20 KNHC 122102
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC SUN MAY 12 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.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 08N92W TO 09N100W 
WHERE LOW LEVEL WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS 
TO 10N113W TO 08N124W TO BEYOND 08N140W. NUMEROUS MODERATE TO 
SCATTERED STRONG CONVECTION WAS NOTED FROM 07N TO 12N BETWEEN 
89W AND 94W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS 
NOTED WITHIN 90 NM N OF AXIS BETWEEN 106W AND 112W. SCATTERED 
MODERATE CONVECTION WAS NOTED WITHIN 90 NM N OF AXIS BETWEEN 
112W AND 122W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 
120 NM N OF AXIS W OF 132W. 

...DISCUSSION... 

A 1025 MB HIGH PRESSURE CENTER IS LOCATED NEAR 32N128W WITH 
RIDGE EXTENDING SE TO NEAR 19N108W. THE PRESSURE GRADIENT 
BETWEEN THE AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE 
VICINITY OF THE ITCZ IS MAINTAINING MODERATE TO FRESH TRADES N 
OF THE ITCZ TO NEAR 20N AND W OF 115W AS DEPICTED BY THE LATEST 
SCATTEROMETER PASSES. THESE WINDS ARE PRODUCING ENOUGH 
CONVERGENCE INTO THE ITCZ TO PRODUCE ACTIVE CONVECTION ALONG THE 
ITCZ AS MENTIONED IN THE SECTION ABOVE. THE LARGE AREA OF FRESH 
WINDS IS RESULTING IN SEAS TO 9 FT FROM 08N TO 15N W OF 130W AS 
CONFIRMED BY RECENT ALTIMETER PASS.

A DISSIPATING STATIONARY FRONT IS IN THE FAR NW PART OF THE 
FORECAST AREA. UPPER SUPPORT FOR THIS FEATURE HAS LIFTED 
OUT...AND THE BOUNDARY WILL DISSIPATE OVER THE NEXT 24 HOURS. 
HIGH PRES BEHIND THE DYING FRONT WILL BUILD E AND MERGE WITH THE 
HIGH PRES NEAR 128W. THIS WILL MAINTAIN THE AREA OF MODERATE TO 
FRESH TRADES AND SEAS TO 8 FT MENTIONED ABOVE. 

LATEST SATELLITE OBSERVATIONS ALONG WITH SATELLITE HOVMOLLERS 
INDICATES THE CARIBBEAN WAVE/TROUGH IS IN THE EASTERN PACIFIC 
ROUGHLY ALONG 92W WITH ASSOCIATED SURFACE LOW PRESSURE NEAR 
08.5N92W EMBEDDED WITHIN THE MONSOON TROUGH. THE WAVE/TROUGH AND 
ASSOCIATED LOW ARE EXPECTED TO DRIFT WESTWARD ACROSS THE 
TROPICAL E PACIFIC THROUGH MID WEEK. IN ADDITION TO ENHANCED 
CONVECTION ASSOCIATED WITH THIS FEATURE...GAP WINDS THROUGH THE 
GULF OF PAPAGAYO WILL REACH 25 KT EACH MORNING WITH SEAS 
REACHING 8 FT WITHIN AND DOWNWIND OF THE GULF OF PAPAGAYO. AS 
THE WAVE/TROUGH CONTINUES TO SHIFT WESTWARD...GAP WINDS TO 30 KT 
WILL BE INDUCED THROUGH THE GULF OF TEHUNATEPEC BY MON MORNING. 
 
$$
AL