000
AXPZ20 KNHC 022150
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU JUN 2 2011

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 
2145 UTC.
 
...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM 10N85W TO 10N110W TO 08N119W. 
A LOW LEVEL TROUGH EXTENDS FROM 09N99W TO 14N99W WITH SEVERAL 
CYCLONIC SWIRLS NOTED ALONG THE TROUGH AXIS. THE INTERTROPICAL 
CONVERGENCE ZONE EXTENDS FROM 08N119W TO 05N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION IS NOTED FROM 03N TO 16N TO 
THE E OF 104W. SCATTERED MODERATE CONVECTION IS DISSIPATING 
WITHIN 120 NM N OF THE ITCZ AXIS BETWEEN 110W AND 115W.

...DISCUSSION...
AN UPPER TROUGH ALONG THE WESTERN CONUS CONTINUES S INTO THE 
DISCUSSION AREA FROM 32N123W TO 16N130W. AN UPPER ANTICYCLONE IS 
CENTERED AT 16N124W WITH A RIDGE EXTENDING NE TO A SHARP CREST 
AT 25N107W. A BAND OF UPPER MOISTURE PRECEDES THE UPPER TROUGH 
OVER THE BAJA CALIFORNIA PENINSULA AND NORTHERN OLD MEXICO... 
FANNING OUT OVER MOST OF THE S CENTRAL CONUS. A SECOND BAND OF 
UPPER MOISTURE IS ROTATING E THROUGH THE UPPER TROUGH AND IS 
ALREADY MOVING ACROSS SOUTHERN CALIFORNIA. UPPER MOISTURE IS 
SPREADING E OVER THE DISCUSSION AREA FROM 17N TO 25N W OF 135W.

AN UPPER RIDGE EXTENDS E OVER THE TROPICS S OF 10N W OF 135W. 
ASSOCIATED UPPER DIFFLUENCE IS ENHANCING CONVECTION ALONG THE 
ITCZ W OF THE AREA BETWEEN 140W AND 150W...WITH THE DEBRIS 
MOISTURE REMAINING W OF 139W. THE UPPER FLOW IS ALSO SOMEWHAT 
DIFFLUENT OVER THE ITCZ BETWEEN 110W AND 126W...AND ENHANCED THE 
CONVECTION PREVIOUSLY DESCRIBED...WITH THE DEBRIS MOISTURE 
ADVECTED S OVER THE AREA FROM 10N TO THE EQUATOR BETWEEN 110W 
AND 127W. OTHERWISE THE UPPER LEVELS APPEAR DRY W OF 110W.

AN UPPER TROUGH IS BUILDING SW ACROSS SOUTHERN OLD MEXICO INTO 
AN UPPER CYCLONE NEAR 10N103W. UPPER DIFFLUENCE OVER THE E 
SEMICIRCLE OF THIS CYCLONE IS ENHANCING CONVECTION ALONG THE LOW 
LEVEL TROUGH EMBEDDED IN THE MONSOON TROUGH FROM 09N TO 14N 
ALONG 99W. 
   
AN UPPER ANTICYCLONE IS CENTERED OVER THE CENTRAL CARIBBEAN WITH 
A RIDGE EXTENDING SW TO A CREST OVER THE E PACIFIC NEAR 11N92W. 
SOME OF THE DEBRIS MOISTURE FROM THE PREVIOUSLY DESCRIBED 
CONVECTION WITHIN THE MONSOON TROUGH IS ADVECTED S ACROSS THE 
EQUATOR BETWEEN 80W AND 101W...AND SOME MOISTURE ALSO SPREADS NE 
AROUND THE UPPER RIDGE ACROSS CENTRAL AMERICA THEN TURNING E 
ACROSS THE CARIBBEAN.

AT THE LOW LEVELS A RIDGE EXTENDS FROM 32N142W TO 17N105W. THE 
GRADIENT IS CURRENTLY SUPPORTING NORTHERLY WINDS TO 20 KT OVER 
THE WATERS N OF 24N E OF 123W. NE TRADES ARE ALSO ENHANCED S OF 
THE RIDGE WITHIN THE AREA FROM 08N TO 24N BETWEEN 133W AND 140W. 
THE GRADIENT IS EXPECTED RELAX ON FRI WITH ONLY A SMALL AREA OF 
NE TRADES AT 15 TO 20 KT PERSISTING ONLY NEAR 12N137W BY LATE 
SAT. SOUTHERLY SWELLS ARE STILL PREDOMINATE OVER THE ENTIRE AREA 
E OF 120W BUT NORTHERLY SWELLS ARE EXPECTED TO MOVE INTO THE 
AREA AND BECOME DOMINATE OVER THE AREA E OF 115W BY LATE FRI AS 
THE S SWELLS SUBSIDE.
 
GAP WINDS...NORTHERLY WINDS AT 20 TO 25 KT WILL CONTINUE TO 
SURGE THROUGH THE CHIVELA PASS AND INTO AND DOWNSTREAM OF THE 
GULF OF TEHUANTEPEC THROUGH TONIGHT...THEN DIMINISH TO LESS THAN 
20 KT BY LATE FRI. THE ASSOCIATED NE SWELLS WITH CONTINUE TO MIX 
WITH CROSS EQUATORIAL SW SWELLS THROUGH FRI...THEN BOTH SWELL 
COMPONENTS WILL DISSIPATE WITH COMBINED SEAS SUBSIDING TO THE 6 
TO 8 FT RANGE OVER THE TROPICS E OF 110W.  

$$
NELSON