000
AXPZ20 KNHC 291525
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN APR 29 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 EXTENDS FROM 10N86W TO LOW PRES NEAR 05N102W 1010 
MB TO ANOTHER LOW PRES NEAR 06N117W 1011 MB. ITCZ AXIS STRETCHES 
FROM 06N117W TO 03N140W. SCATTERED TO NUMEROUS MODERATE TO 
STRONG CONVECTION IS NOTED FROM 04N TO 07N BETWEEN 98W AND 105W 
IN ASSOCIATION WITH THE FIRST LOW PRES ALONG THE MONSOON TROUGH. 
SCATTERED MODERATE CONVECTION IS FROM 03N TO 08N BETWEEN 84W AND 
98W. SIMILAR CONVECTION CAN BE FOUND FROM 03N TO 06N BETWEEN 
123W AND 140W... AND WITHIN 180 NM N OF ITCZ AXIS W OF 138W. 

...DISCUSSION...
STRONG 1033 MB HIGH PRES IS CENTERED NEAR 34N142W WITH A RIDGE 
EXTENDING SE TO NEAR 17N115W. THE PRESSURE GRADIENT BETWEEN THIS 
FEATURE AND TROUGH ASSOCIATED WITH THE INTERTROPICAL CONVERGENCE 
ZONE IS MAINTAINING FRESH N-NE WINDS IN A BROAD AREA ROUGHLY W 
OF LINE 30N120W TO 20N130W AND FROM 05N TO 20N W OF 128W. THE 
MOST RECENT SCATTEROMETER PASSES ALONG WITH FEW SHIP OBSERVATIONS
CONFIRMED THE PRESENCE OF THESE WINDS. THE AREA OF HIGH PRESSURE 
WILL SLOWLY SHIFT W AND SLIGHTLY WEAKEN OVER THE NEXT TWO 
DAYS...WHICH WILL ALLOW THE REGION OF HIGHEST TRADES AND 
WIND-DRIVEN SEAS TO GRADUALLY SHIFT W OF 130W BY MON.

GALE FORCE WINDS N OF THE AREA ALONG THE CALIFORNIA COAST HAS 
BROUGHT NLY SWELL INTO THE N PART OF THE AREA...WITH COMBINED 
SEAS TO 12 FT N OF 27N BETWEEN 118W AND 127W. MODEL GUIDANCE 
SHOWS A TROUGH DEVELOPING SW OF SAN DIEGO LATER TODAY AND 
PERSISTING THROUGH MON NIGHT. THE TROUGH WILL REDUCE THE PRES 
GRADIENT ALONG THE COAST OF SOUTHERN CALIFORNIA AND ALLOW SEAS 
TO GRADUALLY SUBSIDE TO 8-9 FT N OF 27N E OF 123W THE NEXT TWO 
DAYS.

E OF 110W...GENTLE TO MODERATE BREEZE AND SEAS BELOW 8 FT ARE 
NOTED WITH CROSS EQUATORIAL SW SWELL WITH PERIODS IN THE 13-15 
SECOND RANGE. LITTLE CHANGE TO THIS SYNOPTIC WEATHER PATTERN IS 
EXPECTED THROUGH TUE. HOWEVER...WINDS AND SEAS WILL BE HIGHER 
NEAR THE TSTMS ASSOCIATED WITH THE AFOREMENTIONED LOW PRES ALONG 
THE MONSOON TROUGH.

$$
GR