000
AXPZ20 KNHC 182128
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON APR 18 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 
2030 UTC.

...ITCZ...

AXIS EXTENDS FROM 06N77W TO 04N81W TO 07N91W TO 05N95W TO 
06N101W TO 05N109W TO 04N127W TO 04N133W TO 01N140W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION WITHIN 60 NM OF ITCZ AXIS 
BETWEEN 88W AND 92W. SCATTERED MODERATE CONVECTION WITHIN 90 NM 
N OF THE ITCZ AXIS BETWEEN 133W AND 137W. A SURFACE TROUGH IS 
EMBEDDED WITHIN THE ITCZ FROM 07N94W TO 03N92W AND A SECOND FROM 
09N106W TO 05N112W. SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION WITHIN 60/75 NM OF TROUGH AXIS BETWEEN 03N AND 05N.  
SCATTERED MODERATE CONVECTION NW OF TROUGH AXIS FROM 07N TO 09N 
BETWEEN 106W AND 110W. 

...DISCUSSION...

A 1023 MB HIGH PRES NEAR 30N135W EXTENDS A BROAD RIDGE AXIS 
ACROSS NW PORTION OF DISCUSSION AREA TO AROUND 17N117W. PRES 
GRADIENTS ON SOUTHERN AND EASTERN PERIPHERY ARE FAIRLY WEAK AND 
AS A RESULT WINDS ACROSS ENTIRE NE PACIFIC BASIN ARE LESS THAN 
20 KT. ONLY REMAINING AREA OF MODERATE 10-15 KT WINDS ARE W OF 
BAJA CALIFORNIA TO 120W AND IN THE TRADE WIND BELT BETWEEN 5N 
AND 10N W OF 130W. AS A CONSEQUENCE OF THE LIGHT WINDS SEA 
HEIGHTS CONTINUE TO SUBSIDE...AND ARE GENERALLY 5-7 FT.

LOOKING AHEAD...MODEL GUIDANCE SUGGESTS VERY LITTLE CHANGE TO THE
CURRENT DOWNWARD TREND IN WINDS AND SEAS. THE HIGH WILL GRADUALLY
SHIFT S OVER THE NEXT DAY OR TWO TO AROUND 26N135W BY EARLY WED. 
A THERMAL TROUGH OVER THE MOJAVE DESERT IN THE SW U.S. TIGHTENS 
THE PRES GRADIENT ENOUGH TO SUPPORT 20 KT WINDS LATE THU THROUGH 
FRI WITHIN 150 NM W OF THE BAJA PENINSULA...BUT OTHERWISE BENIGN 
MARINE CONDITIONS ARE EXPECTED TO PREVAIL OVER THE EASTERN 
PACIFIC THROUGH SAT.

VERY LONG PERIOD 19-20 SEC CROSS-EQUATORIAL SW SWELL WILL SWEEP 
NE TUE THROUGH SAT...REACHING THE COASTS OF MEXICO AND 
CENTRAL AMERICA THU EVENING. SEA HEIGHTS WILL BE LESS THAN 8 FT 
BUT HIGH ENERGY SWELL WILL RESULT IN HAZARDOUS SURF AT COASTAL 
LOCATIONS.

$$
PAW