000
AXPZ20 KNHC 080955
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1005 UTC WED MAY 08 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH AXIS EXTENDS FROM 04N77W TO 09N102W TO 08N110W TO
09N125W THEN AS ITCZ TO 09BN120W TO 07N128W TO BEYOND 07N140W.
SCATTERED MODERATE CONVECTION WITHIN 150 NM S OF AXIS FROM 92W 
TO 94W AND WITHIN 150 NM N OF AXIS FROM 113W TO 118W. 

...DISCUSSION...
UPPER LEVEL ANTICYCLONE AT 12N110W ANCHORS BROAD STEADY RIDGE.
ABUNDANT TROPICAL MOISTURE HEADS NE ON WESTERN PERIPHERY OF RIDGE
ON 90 KT JETSTREAM REACHING BAJA CALIFORNIA TODAY.  SHARP 
UPSTREAM TROUGH FROM 32N128W TO 17N140W DRIES AIR MASS WITHIN 5
DEGREES OF AXIS.  SECOND UPPER LEVEL TROUGH DIGS SW FROM EL
SALVADOR TO 00N92W BRINGS DRY AIR MASS TO TROPICAL LATITUDES.
AREA OF DIVERGENCE ALOFT W OF TROUGH AXIS HAS LITTLE MOISTURE
TO DEVELOP CONVECTION ALONG MONSOON TROUGH...EXCEPT SCATTERED
TSTMS FROM 92W-94W.      

...ELSEWHERE AT LOWER LEVELS...  
WEAK HIGH PRES CENTER AT 25N122W WITH SURFACE RIDGE EXTEND W-SW
TO BEYOND 24N140W.  PRES GRADIENT REMAINS WEAK ACROSS MOST OF 
BASIN WITH GENTLE TO MODERATE WINDS PREVAILING ACROSS REGION...
EXCEPT IN LOWER LATITUDES N OF ITCZ WHERE FRESH NE TRADES MAY
PREVAIL.  SEAS REMAIN BELOW 8 FT ACROSS ENTIRE DOMAIN. 
 
...OUTLOOK...
SURFACE RIDGE STRENGTHENS THROUGH SAT EXPANDING REGION OF FRESH
NE TRADES N OF ITCZ W OF 120W.  RIDGE ABLE TO DEFLECT INCOMING 
COLD FRONT NE THU...BUT FRESH SOUTHERLY BREEZE MAY ENCROACH INTO
NW CORNER OF BASIN.  LITTLE CHANGE ELSEWHERE.  
  
$$
WALLY BARNES