000
AXPZ20 KNHC 301527
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON APR 30 2012

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1445 UTC.

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

MONSOON TROUGH 09N85W TO 06N105W...THEN ITCZ TO 06N119W TO 
04N120W TO 03N140W. CLUSTER OF MODERATE TO STRONG CONVECTION 
FROM 05N TO 07N E OF 79W. SIMILAR CONVECTION IS NOTED WITHIN 140 
NM S OF TROUGH BETWEEN 90W AND 95W. ISOLATED MODERATE FROM 05N 
TO 09N BETWEEN 95W AND 100W. A SHORTWAVE IS HELPING TO INDUCE 
THIS CONVECTIVE ACTIVITY.

...DISCUSSION...

W OF 110...NEARLY STATIONARY 1032 MB HIGH PRES CENTERED NEAR 
33N146W EXTENDS A RIDGE SE ACROSS THE FORECAST WATERS TO NEAR 
16N115W. THE PRESSURE GRADIENT ASSOCIATED WITH THIS AREA OF HIGH 
PRES IS RECEDING AWAY FROM THE W COAST OF BAJA CALIFORNIA AS THE 
HIGH SLOWLY SHIFTS W INTO THE CENTRAL PACIFIC. A SURFACE TROUGH 
HAS DEVELOPED JUST W OF THE COAST OF BAJA CALIFORNIA AND EXTENDS 
FROM 30N117W TO 26N116W TO 21N118W. WINDS ARE PRETTY LIGHT IN 
ASSOCIATION WITH THIS TROUGH WHICH IS FORECAST TO GRADUALLY 
DISSIPATE IN ABOUT 24-36 HOURS. PRES GRADIENT BETWEEN THE TROUGH 
AND THE HIGH PRES IS PRODUCING AN AREA OF FRESH TO STRONG N TO 
NE WINDS W OF A LINE FROM 30N124W TO 20N135W. A COUPLE OF SHIP 
OBSERVATIONS ALONG WITH SCATTEROMETER DATA SHOWED AN AREA OF 
20-25 KT N TO NE WINDS N OF 22N W OF 128W. WINDS AND SEAS WILL 
CONTINUE TO DIMINISH ACROSS THE N WATERS OVER THE NEXT COUPLE OF 
DAYS AS THE HIGH WEAKENS AND THE PRES GRADIENT RELAXES ACROSS 
THE BASIN. FOR THE SAME REASON...THE AERIAL EXTENT AND STRENGTH 
OF THE TRADES WILL ALSO DECREASE. CURRENTLY...TRADE WINDS OF 20 
KT COVER THE AREA FROM 07N TO 20N W OF 135W...AND FROM 06N TO 
15N BETWEEN 125W AND 135W.

E OF 110W...NOT MUCH OF INTEREST AS THERE ARE NO GAP WINDS AND 
THE DEEP CONVECTION IS CONFINED TO THE MONSOON TROUGH. GENTLE TO 
MODERATE BREEZE WILL PERSIST WITH SEA HEIGHTS BELOW 8 FT. 

$$
GR