000
AXPZ20 KNHC 110258
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                          
0405 UTC THU APR 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
MONSOON TROUGH AXIS EXTENDS FROM 08N79W TO 07N75W 07N98W. ITCZ 
AXIS EXTENDS FROM 07N98W TO 07N110W 09N120W 06N128W 05N140W. 
SCATTERED MODERATE CONVECTION EXISTS FROM 02N TO 08N BETWEEN 82W 
AND 97W...AND ALSO FROM 04N TO 10N BETWEEN 116W AND 134W. 

...DISCUSSION...                                             

WATER VAPOR IMAGERY SHOWS AN UPPER TROUGH THAT EXTENDS FROM THE 
CENTRAL PORTION OF THE U.S. SW ACROSS N MEXICO SW TO SOUTHERN 
BAJA CALIFORNIA AND TO NEAR 18N114W. THE TROUGH MARKS A REGION 
WHERE A STRONG POLAR JET MERGES WITH A RATHER POTENT SUBTROPICAL 
JET STREAM BRANCH THAT ENTERS THE DISCUSSION AREA AT 
21N140W...AND CONTINUES E AND ESE TO ACROSS THE BASE OF THE THE 
TROUGH AND THEN NE TO ACROSS CENTRAL MEXICO TO ACROSS THE NW 
GULF OF MEXICO AND TO THE CENTRAL U.S. THE CYCLONIC CIRCULATION 
AND TROUGH IS FORECAST TO LIFT NEWD THROUGH THU NIGHT. A 
MID/UPPER TROUGH SHIFTING EWD IS JUST TO THE SE OF THE 
AFOREMENTIONED TROUGH ALONG A POSN FROM NEAR 18N111W TO 14N105W 
TO 07N104W. DIFFLUENCE FLOW ALOFT ACROSS THE SOUTHERN PORTION OF 
THE TROUGH IS HELPING TO SUSTAIN SMALL CLUSTERS OF TSTMS WITHIN 
45 NM EITHER SIDE OF LINE FROM 11N109W TO 11N114W.

A NEARLY STATIONARY ANTICYCLONE OF 1032 MB CENTERED N OF THE 
AREA NEAR 35N137W EXTENDS A BROAD RIDGE ACROSS THE SUBTROPICS W 
OF ABOUT 112W. PRES GRADIENT ALONG THE COAST OF S CALIFORNIA 
CONTINUES TO RELAX AS A SURFACE LOW IN E MEXICO SHIFTS FURTHER 
EASTWARD. AN ASCAT PASS FROM WED AFTERNOON HIGHLIGHTED FRESH TO 
STRONG NE TRADES S OF THE SUBTROPICAL HIGH FROM ABOUT 14N TO 29N 
W OF 128W. A WEAK SURFACE TROUGH IS ANALYZED FROM 10N122W TO 
06N123W IS MOVING W ABOUT 17 KT. THIS TROUGH IS SLIGHTLY 
ENHANCING CONVECTION ALONG AND NEAR THE ITCZ. GLOBAL MODEL 
GUIDANCE INDICATES THE NEAR EQUATORIAL CONVERGENCE ZONE WILL 
WEAKEN IN THE NORTHERN HEMISPHERE OVER THE NEXT COUPLE OF DAYS 
WITH THE ITCZ AXIS SHIFTING S OF THE EQUATOR. THIS WILL CONTINUE 
TO WEAKEN THE TRADES ACROSS THE DISCUSSION AREA AS THE 1032 MB   
WEAKENS SOME. A TIGHT PRES GRADIENT ASSOCIATED WITH THE ABOVE 
MENTIONED RIDGE IS INDUCING A SWATH OF NE 20-25 KT WINDS WITH 
SEAS TO 9 FT BETWEEN A LINE FROM 30N122W TO 21N129W TO 09127W TO 
08N140W AND A LINE FROM 30N133W TO 26N140W. THIS GRADIENT WILL
SLACKEN ENOUGH BY FRI TO ALLOW FOR THIS WINDS TO EXIST MAINLY
OVER THE N CENTRAL PORTION OF THE AREA BUT WITH DIRECTION FROM 
THE NW-N WITH SEAS OF 8-10 FT THAT MARK THE LEADING EDGE OF A 
NEW NW SWELL TRAIN. WINDS ELSEWHERE SE OF THE AFOREMENTIONED 
LINES ARE EXPECTED TO BE IN THE RANGE OF 10-15 KT. 

$$
AGUIRRE