000
AXPZ20 KNHC 192134
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE APR 19 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 EXTENDS FROM 07N77W TO 
06N92W TO 04N100W TO 06N110W TO 03N122W TO 04N132W TO 03N140W. 
SCATTERED MODERATE CONVECTION IS FROM 04N TO 07N BETWEEN 88W AND 
92W. SCATTERED MODERATE IS ALSO NOTED WITHIN 60 NM OF AXIS 
BETWEEN 118W AND 113W.

...DISCUSSION...

A 1024 MB HIGH PRES LOCATED NEAR 27N130W EXTENDS A RIDGE SE TO 
NEAR 18N109W. THIS FEATURE WILL REMAIN NEARLY STATIONARY DURING 
THE NEXT 24 HOURS. A SMALL AREA OF 20 KT TRADE WINDS IS NOTED ON 
THE SOUTHERN PERIPHERY OF THE RIDGE FROM 05N TO 11N W OF 125W. 
AN EARLIER WINDSAT PASS PROVIDED OBSERVATIONS OF THESE WINDS.  
MODEL GUIDANCE INDICATES LITTLE CHANGE OF THIS WEATHER PATTERN 
DURING THE NEXT COUPLE OF DAYS. 

THE 1918 UTC EXPERIMENTAL ASCAT 25 KM COASTAL WINDS SHOWED AND 
AREA OF 20 KT NW WINDS JUST W OF THE BAJA CALIFORNIA PENINSULA 
BUT PARTICULARLY N OF 26N TO 117W. WINDS ARE FORECAST TO 
INCREASE TO 25 KT BY THU AS PRES GRADIENT BETWEEN HIGH PRES N OF 
AREA AND LOWER PRES OVER MEXICO TIGHTENS.

A PAIR OF WEAK COLD FRONTS WILL CLIP THE EXTREME NW PART OF THE 
DISCUSSION AREA WITH LITTLE EFFECT OTHER THAN A SHIFT IN WIND DIR
AND SLIGHTLY HIGHER NW SWELL BEHIND THE FRONTS. THE FIRST FRONT 
WILL PASS CLOSE TO 30N140W THIS EVENING...AS A DISSIPATING FRONT 
EXTENDING OVER THE FAR NW PART OF THE FORECAST REGION TONIGHT 
AND WED. THE NEXT FRONT WILL BRUSH THE FAR NW PART FRI NIGHT 
INTO SAT. 

WEAK CYCLONIC CIRCULATION IS NOTED ON VISIBLE SATELLITE PICTURES 
NEAR 06N93W. A SURFACE TROUGH IS ANALYZED ALONG 93W FROM 02N TO 
09N. MODELS GUIDANCE SUGGESTS THAT THIS WEAK SYSTEM WILL DRIFT 
WNW OVER THE NEXT SEVERAL DAYS. AS MENTIONED IN THE ITCZ 
SECTION...SCATTERED MODERATE CONVECTION IS OBSERVED E OF THE 
TROUGH AXIS FROM 04N TO 07N BETWEEN 88W AND 92W. 

VERY LONG PERIOD 19-20 SEC CROSS-EQUATORIAL SW SWELL WILL SWEEP 
NE ACROSS THE WATERS THE REMAINDER OF THE WEEK...REACHING COASTAL
AREAS OF SOUTHERN CALIFORNIA...MEXICO AND CENTRAL AMERICA THU. 
WHILE SEA HEIGHTS WILL BE LESS THAN 8 FT AS THE SWELL PROPAGATES 
AWAY FROM THE EQUATOR...THIS HIGH ENERGY SWELL WILL STILL RESULT 
IN VERY HAZARDOUS SURF CONDITIONS AT COASTAL LOCATIONS INCLUDING 
AN ENHANCED RIP CURRENT DANGER THU THROUGH SAT.

$$
GR