000
AXPZ20 KNHC 092119
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT APR 09 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS WAS ANALYZED FROM 05N80W 
TO 05N120W TO 02N140W. SCATTERED MODERATE TO STRONG WITHIN 180 
NM N AND 90 NM S OF AXIS BETWEEN 80W AND 90W. SCATTERED MODERATE 
ISOLATED STRONG WITHIN 30 NM OF AXIS BETWEEN 122W AND 124W. 

...DISCUSSION...

SURFACE HIGH PRESSURE 1030 MB IS CENTERED NEAR 33N141W WITH 
RIDGE EXTENDING SE INTO THE AREA NEAR 25N121W. A TROUGH OF LOW 
PRESSURE EXTENDS FROM THE CENTRAL BAJA PENINSULA SW TO 20N123W. 
THE PRESSURE GRADIENT BETWEEN THE RIDGE AND TROUGH IS SUPPORTING 
FRESH NW TO N 20 KT WINDS N OF 22N BETWEEN 120W AND 130W. THE 
NORTHERLY WINDS WILL DIMINISH BELOW 20 KT BY TOMORROW AFTERNOON 
AS THE TROUGH DISSIPATES. THE PRESSURE GRADIENT BETWEEN THE 
RIDGE AND LOWER PRESSURES IN THE VICINITY OF THE ITCZ IS 
SUPPORTING FRESH 20 KT TRADES FROM 08N TO 22N W OF 130W. THE 
TRADES WILL EXPAND EASTWARD ALL THE WAY TO 115W AS THE RIDGE 
EXTENDS FURTHER SE INTO THE AREA. MEANWHILE LARGE NW SWELLS TO 
15 FT WITH WAVE PERIODS OF 13 TO 15 SECONDS ARE PROPAGATING 
ACROSS THE NE WATERS W OF BAJA CALIFORNIA WITH SWELLS TO 8 FT 
REACHING TO 01N. THESE SWELLS WILL GRADUALLY DECAY TO 8 TO 10 FT 
BY 48 HOURS.

NE TO E WINDS WILL CONTINUE TO PULSE TO 20 KT IN THE GULF OF 
PAPAGAYO DURING THE NEXT FEW DAYS WITH SEAS REMAINING JUST BELOW 
8 FT. THE LARGEST AREAL EXTENT OF THE 20 KT WINDS WILL BE IN 
THE EARLY MORNING HOURS WITH THE AID OF NOCTURNAL DRAINAGE FLOW. 

GULF OF CALIFORNIA...FRESH 20 KT NORTHERLY WINDS ARE EXPECTED TO 
COMMENCE IN THE CENTRAL GULF SUN MORNING. THESE WINDS WILL 
EXPAND TO ENCOMPASS THE MAJORITY OF THE GULF MON MORNING AS THE 
PRES GRADIENT TIGHTENS BETWEEN THE EXPANDING RIDGE W OF THE BAJA 
CALIFORNIA PENINSULA AND A LOW PRES SYSTEM MOVING THROUGH 
SOUTHERN TEXAS AND NE MEXICO. SEAS ARE EXPECTED TO REMAIN LESS 
THAN 8 FT IN THE GULF THROUGH THE PERIOD.

$$
AL