000
AXPZ20 KNHC 180923
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON APR 18 2011

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS WAS ANALYZED FROM 04N77W 
TO 05N95W TO 05N110W TO 06N125W TO 00N140W. SCATTERED MODERATE 
AND ISOLATED STRONG CONVECTION WAS WITHIN 150 NM N OF THE AXIS 
BETWEEN 105W AND 110W AND ALSO FROM 07N TO 09N BETWEEN 122W AND 
129W. SIMILAR CONVECTION WAS WITHIN 120 NM S OF THE AXIS BETWEEN 
123W AND 126W.

...DISCUSSION...

ALOFT...UPPER RIDGING REACHES FROM NEAR 32N128W SW TROUGH 25N140W
TO THE BIG ISLAND OF HAWAII. A MID TO UPPER LEVEL TROUGH IS JUST 
E OF THIS RIDGE FROM 32N123W SW THROUGH 25N135W TO 20N140W. MID 
TO UPPER LEVEL MOISTURE IS BEING ADVECTED NE TOWARD THE NORTHERN 
BAJA CALIFORNIA PENINSULA WITHIN 180 NM E OF THE TROUGH AXIS BY 
A 40-55 KT JET. A MAINLY ZONAL FLOW PATTERN EXISTS ACROSS THE 
REMAINDER OF THE WATERS N OF 17N E OF 130W. THE SOUTHERN WATERS 
ARE DOMINATED BY NEARLY SOLID UPPER LEVEL RIDGING ALONG 10N FROM 
WESTERN COSTA RICA TO 140W. SPORADIC CLUSTERS OF CONVECTION ARE 
BEING ENHANCED ALONG THE ITCZ UNDER DIFFLUENT FLOW JUST S OF 
THIS RIDGING.

AT THE SURFACE...THE MAJORITY OF THE WATERS ARE CHARACTERIZED BY 
BENIGN MARINE CONDITIONS. 1024 MB HIGH PRES IS LOCATED NEAR 
30N137W WITH A RIDGE EXTENDING SE TO NEAR 16N113W. A SMALL AREA 
OF NW-N 20 KT WINDS EXIST N OF 27N BETWEEN 118W AND 123W...ALONG 
WITH 8-10 FT NW SWELL...WHERE THE PRES GRADIENT IS THE TIGHTEST 
ALTHOUGH WINDS AND SEAS WILL DIMINISH/SUBSIDE THERE TO LESS THAN 
20 KT/8 FT BY 24 HOURS AS THE HIGH WEAKENS TO 1022 MB. ELSEWHERE 
LINGERING 8 FT MIXED NE AND SW SWELL REMAINS OVER THE SW 
PORTION. SEAS WILL CONTINUE TO DECAY TO LESS THAN 8 FT BY THIS 
EVENING.

VERY LONG PERIOD 19-21 SECOND CROSS-EQUATORIAL SOUTHWESTERLY 
SWELL WILL PROPAGATE ACROSS THE WATERS THROUGH THE WEEK REACHING 
THE COASTLINES OF SOUTHERN CALIFORNIA SE ALL THE WAY TO COLOMBIA 
THU EVENING. WHILE SEA HEIGHTS WILL BE LESS THAN 8 FT...THIS 
HIGH ENERGY SWELL WILL STILL RESULT IN HAZARDOUS SURF CONDITIONS 
AT COASTAL LOCATIONS.

$$
LEWITSKY