000
AXPZ20 KNHC 040320
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE MAY 04 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0245 UTC.

...ITCZ...

THE ITCZ AXIS IS ANALYZED ALONG 08N83W TO 05N94W TO 08N105W TO 
03N120W TO 05N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION PERSISTS WITHIN 120 NM EITHER SIDE OF A LINE FROM 
04N80W TO 07N95W TO 07N105W. ISOLATED CLUSTERS OF CONVECTION ARE 
FLARING INTERMITTENTLY WITHIN 30 NM EITHER SIDE OF A LINE FROM 
04N112W TO 04N140W. 

...DISCUSSION...

AN UPPER CYCLONE HAS CUT OFF NEAR 21N131W AND IS DROPPING S INTO 
AN UPPER TROUGH DOMINATING THE DISCUSSION AREA N OF 07N BETWEEN 
137W AND 118W. AN UPPER ANTICYCLONE IS CENTERED W OF THE AREA 
NEAR 10N148W WITH AN UPPER RIDGE EXTENDING NE TO A CREST NEAR 
34N140W. UPPER MOISTURE IS JUST BEGINNING TO SPILL ACROSS THE 
RIDGE INTO THE AREA N OF 20N ALONG 140W. OTHERWISE...THE UPPER 
LEVELS APPEAR VERY DRY N OF 08N W OF 116W AND N OF 13N E OF 116W.

AN UPPER RIDGE EXTENDS INTO THE AREA FROM 16N96W TO A SHARP 
CREST AT 05N124W. E PACIFIC ITCZ CONVECTION IS ENHANCED UNDER 
THIS RIDGE FROM COLOMBIA TO 121W. RESULTANT DEBRIS MOISTURE 
FANS OUT OVER THE AREA S OF 10N WITH SOME OF THE MOISTURE 
SPREADING S OF THE EQUATOR TO THE E OF 96W. SOME OF THE MOISTURE 
SPREADS N ACROSS THE UPPER RIDGE TO ALONG 15N. 

AN UPPER CYCLONE OVER THE CARIBBEAN BEAR 17N78W IS PROGRESSING W 
WITHIN AN UPPER TROUGH DIPPING S ACROSS CENTRAL AMERICA TO A 
BASE AT 09N88W. VERY DRY UPPER AIR IS NOTED NE OF LINE FROM THIS 
TROUGH BASE TO THE UPPER RIDGE AT 16N97W...BUT CONVECTION IS 
ENHANCED OVER GUATEMALA AND IS ABOUT TO MOVE OFFSHORE AT 
14N92W.   

ELSEWHERE AT THE SURFACE...
A BROAD RIDGE DOMINATES THE WITH ITS AXIS MEANDERING FROM ABOUT 
32N137W TO NEAR 10N97W. NE TRADES TO THE S OF THE RIDGE AXIS ARE 
AT 15 TO 20 KT...WITH SEAS 8 TO 10 FT IN NE SWELL...EXCEPT 
SOUTHERLY SWELL IS NOW BECOMING THE PRIMARILY COMPONENT AS FAR N 
AS 20N S OF THE RIDGE. NORTHERLY WINDS N OF 25N BETWEEN 126W AND 
137W ARE AT 15 TO 20 KT WITH SEAS HEIGHTS TO 10 FT IN N SWELL.

GAP WINDS...NE WINDS ARE EXPECTED TO SURGE INTO THE GULF OF 
PAPAGAYO AT 15 TO 20 KT BRIEFLY ON TUE. NW WINDS AT 15 TO 20 KT 
OVER THE GULF OF CALIFORNIA SHOULD DIMINISH BELOW 20 KT EARLY 
TUE MORNING.  
    
$$
NELSON